[Federal Register Volume 91, Number 37 (Wednesday, February 25, 2026)]
[Rules and Regulations]
[Pages 9140-9169]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2026-03744]
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FEDERAL COMMUNICATIONS COMMISSION
47 CFR Parts 0 and 15
[ET Docket No. 18-295 and GN Docket No. 17-183; FCC 26-1; FR ID 331544]
Unlicensed Use of the 6 GHz Band; Expanding Flexible Use in Mid-
Band Spectrum Between 3.7 and 24 GHz
AGENCY: Federal Communications Commission.
ACTION: Final rule.
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SUMMARY: In this document, the Federal Communications Commission
(Commission or FCC) adopts rules allowing unlicensed geofenced variable
power (GVP) devices to operate in the U-NII-5 and U-NII-7 portions of
the 6 GHz band (5.925-7.125 GHz) at up to 11 dBm/MHz EIRP power
spectral density and 24 dBm EIRP. GVP devices must use geofencing
systems to prevent harmful interference to licensed microwave links and
radio astronomy observatories. The geofencing systems will calculate
exclusion zones where GVP devices cannot operate on specified
frequencies. Each GVP access point must have a geolocation capability
to determine its location and avoid operating on prohibited frequencies
within the exclusion zones. Client devices must operate 6 dB below the
access point's authorized power. These rules permit the GVP devices to
operate at higher power than very lower power 6 GHz band unlicensed
devices.
DATES: This rule is effective April 27, 2026.
FOR FURTHER INFORMATION CONTACT: Nicholas Oros of the Office of
Engineering and Technology, Policy and Rules Division, at 202-418-0636
or [email protected].
SUPPLEMENTARY INFORMATION: This is a summary of the Commission's Fourth
Report and Order, in ET Docket No. 18-295 and GN Docket No. 17-183, FCC
26-1, adopted on January 29, 2026, and released on January 30, 2026.
The full text of this document is available for public inspection and
can be downloaded at https://docs.fcc.gov/public/attachments/FCC-26-1A1.pdf. Alternative formats are available for people with disabilities
(Braille, large print, electronic files, audio format) by sending an
email to [email protected] or calling the Commission's Consumer and
Governmental Affairs Bureau at (202) 418-0530 (voice), (202) 418-0432
(TTY).
Regulatory Flexibility Act. The Regulatory Flexibility Act of 1980,
as amended (RFA) requires that an agency
[[Page 9141]]
prepare a regulatory flexibility analysis for notice and comment
rulemakings, unless the agency certifies that ``the rule will not, if
promulgated, have a significant economic impact on a substantial number
of small entities.'' Accordingly, the Commission has prepared a Final
Regulatory Flexibility Analysis (FRFA) concerning the possible impact
of the rule changes contained in the Fourth Report and Order on small
entities. The FRFA is set forth in Appendix C, https://www.fcc.gov/document/fcc-votes-enable-better-faster-wi-fi-and-next-gen-connectivity-0.
Paperwork Reduction Act. This document does not contain new or
modified information collection requirements subject to the Paperwork
Reduction Act of 1995, Public Law 104-13. In addition, therefore, it
does not contain any new or modified information collection burden
``for small business concerns with fewer than 25 employees,'' pursuant
to the Small Business Paperwork Relief Act of 2002, Public Law 107-198,
44 U.S.C. 3506(c)(4).
Congressional Review Act. The Commission has determined, and the
Administrator of the Office of Information and Regulatory Affairs,
Office of Management and Budget, concurs, that this this rule is
``major'' under the Congressional Review Act, 5 U.S.C. 804(2). The
Commission will send a copy of the Fourth Report and Order to Congress
and the Government Accountability Office pursuant to 5 U.S.C.
801(a)(1)(A).
Synopsis
Introduction
In this document, the Commission adopts rules for geofenced
variable power (GVP) devices to operate in the U-NII-5 (5.925-6.425
GHz) and U-NII-7 (6.525-6.875 GHz) portions of the 6 GHz band at up to
11 dBm/MHz EIRP power spectral density (PSD) and 24 dBm EIRP. GVP
devices must work in tandem with a geofencing system to minimize the
likelihood of a significant risk of harmful interference to licensed
fixed microwave links and radio astronomy observatories. The geofencing
systems will calculate exclusion zones in which the GVP devices will
not be permitted to operate co-frequency with microwave links or in a
portion of the U-NII-7 band used by radio astronomy. Each GVP access
point will be required to have a geolocation capability to determine
its location and avoid operating on prohibited frequencies within the
exclusion zones. GVP client devices will operate under the control of
GVP access points at 6 dB less power than the authorized power of the
controlling GVP access point. Using geofencing will enable GVP devices
to operate at significantly higher power levels than the -5 dBm/MHz
EIRP PSD and 14 dBm EIRP at which non-geofenced very low power (VLP)
devices are permitted to operate. At this time, the Commission is
limiting the GVP device operation to the U-NII-5 and U-NII-7 portions
of the 6 GHz band and defer considering such action for the U-NII-6 and
U-NII-8 bands.
Power Limits for GVP Access Points
In the 6 GHz Second FNPRM (89 FR 874, January 8, 2024), the
Commission sought comment on the appropriate power limits for GVP
devices in the U-NII-5 and U-NII-7 bands. As an initial matter, the
Commission noted that Apple, Broadcom et al. had requested that it
permit VLP devices to operate at up to 1 dBm/MHz EIRP PSD and 14 dBm
EIRP. Based on the technical record, the Commission declined in the 6
GHz Second Order (89 FR 874, January 8, 2024) to adopt this PSD level
and instead limited VLP operations to a maximum of -5 dBm/MHz EIRP PSD
and 14 dBm EIRP. However, the Commission explained that it could allow
GVP devices to operate at a higher PSD level if such devices are
prohibited from operating co-channel and in close proximity to licensed
microwave receive sites. The Commission proposed that VLP devices be
permitted to operate across the entire 6 GHz band--U-NII-5, U-NII-6, U-
NII-7, and U-NII-8--at up to 1 dBm/MHz EIRP PSD and 14 dBm EIRP while
under the control of a geofencing system to minimize the likelihood of
harmful interference to licensed incumbent services. Although the
Commission expressly sought comment on these proposed power limits, it
also asked whether it should allow GVP devices to operate with higher
PSD and EIRP limits. The Commission sought comment on a range of power
limits and specifically asked whether it could ``allow a power limit
higher than 14 dBm EIRP,'' identifying as one such example power levels
``up to 21 dBm EIRP.'' Furthermore, the Commission asked whether ``even
higher PSD and EIRP limits [would] increase the risk of harmful
interference to licensed incumbent services'' and whether ``the
proposed geofencing system . . . [would] be sufficient to reduce this
risk.'' By using the phrase ``even higher,'' the Commission signaled
that it sought comment on power limits higher than those discussed
earlier in the paragraph--i.e., higher than 1 dBm/MHz EIRP PSD and 21
dBm EIRP.
Apple, Broadcom et al. request that GVP devices be permitted to
operate at up to 8 dBm/MHz EIRP PSD and 21 dBm EIRP across the entire 6
GHz band. According to Apple, Broadcom et al., creating geofencing-
capable devices ``will require manufacturers to add expensive new
hardware and software to a wide range of consumer and enterprise
equipment,'' and such investment cannot be justified for the marginal
benefit that would be provided by the proposed power limits. Apple,
Broadcom et al. stress that unless the GVP maximum permitted power is
21 dBm EIRP, consumers will not experience any additional benefit from
a higher PSD when using channels wider than 80-megahertz because total
power transmitted is proportional to the PSD and capping the maximum
EIRP at 21 dBm would allow all channel bandwidths to operate with more
than 14 dBm EIRP total power. They explain that ``increas[ing] power
limits for all channel sizes available in the 6 GHz band . . . is
important because wider channels are subject to more noise and
therefore require additional power to maintain a sufficient signal-to-
noise ratio. Apple, Broadcom et al. similarly recommend permitting a
maximum PSD of 8 dBm/MHz EIRP so that all channels, regardless of
bandwidth, can operate at the maximum power level. They further claim
that ``an increase in the PSD limit would not result in any higher risk
of harmful interference because of the limitations imposed by the
proposed geofencing system'' (e.g., the proposal that ``the size of an
exclusion zone must increase in proportion to a GVP device's power
level'').
Apple, Broadcom et al. point to several computer simulations they
submitted prior to the issuance of the 6 GHz Second FNPRM as evidence
that GVP devices can operate at up to 21 dBm EIRP without creating a
significant risk of harmful interference to licensed incumbents. One
computer simulation that modeled the interaction between outdoor VLP
devices and the 97,888 6 GHz band fixed microwave links in the United
States for 20-, 40-, 80-, and 160-megahertz bandwidth VLP signals
concluded that there was only a 0.00059% probability that a VLP device
operating at 21 dBm EIRP would cause a microwave link to experience an
interference-to-noise (I/N) ratio greater than -6 dB. According to
Apple, Broadcom et al., the computer simulation demonstrates that VLP
devices operating at 21 dBm with no additional mitigation rules would
not create a significant harmful interference
[[Page 9142]]
risk. Apple, Broadcom et al. argued that this minimal risk would be
mitigated by the proposed geofencing rules, which ``would prohibit
transmissions in the very rare instances where the [computer
simulations] found that [VLP] operations could exceed the -6 dB I/N
metric.''
The Dynamic Spectrum Alliance (DSA) and Wi-Fi Alliance support the
same power levels for GVP devices as Apple, Broadcom et al. DSA
believes that the GVP power levels proposed by the Commission, 14 dBm
EIRP and 1 dBm/MHz EIRP PSD, do not ``provide[ ] a sufficient economic
incentive for companies to make the necessary investments [to] develop[
] and commercializ[e] such [devices].'' DSA points out that the
proposed power levels would only benefit devices operating on 20-
megahertz or 40-megahertz channels, but that most use cases are better
suited to larger channel sizes. DSA urges the Commission to instead
adopt a geofenced VLP framework with a 21 dBm EIRP limit and 8 dBm/MHz
EIRP PSD. According to DSA, ``[t]he higher EIRP limit . . . will
provide greater reliability for [augmented reality/virtual reality]
applications,'' and ``[t]he increased EIRP PSD limits will enable
narrow band applications, which may not be feasible under the [current]
VLP limits.'' The Wi-Fi Alliance ask that the Commission ``create a new
device class for higher power VLP devices capable of operating at up to
21 dBm EIRP and 8 dBm/MHz EIRP PSD. According to the Wi-Fi Alliance,
allowing VLP devices to operate at up to 21 dBm EIRP ``will enable new
applications that are not possible at the current VLP power levels and
enable a more robust connectivity for existing applications.''
While Apple initially joined Apple, Broadcom et al. in requesting
GVP power levels of up to 8 dBm/MHz EIRP PSD and 21 dBm maximum EIRP,
Apple later proposed a simplified geofencing version with only two
power levels: 1 dBm/MHz EIRP PSD and 8 dBm/MHz EIRP PSD, both with a
maximum 21 dBm EIRP, instead of permitting variable power up to the 8
dBm/MHz EIRP PSD and 21 dBm EIRP limits. The geofencing systems would
calculate two exclusion zones--one for each PSD level--and a GVP device
would check its location to determine whether it may operate and, if
so, its maximum power level. This version would reduce the calculations
needed by the geofencing systems because they would not need to support
variable GVP power levels.
More recently, Apple and Meta contend that maximum authorized power
levels of at least 11 dBm/MHz PSD and 24 dBm EIRP for GVP access points
and 5 dBm/MHz PSD and 18 dBm EIRP for GVP client devices are
``essential for adequate reliability and performance for GVP use
cases.'' They claim that ``GVP devices are likely to predominately be
wearable devices,'' such as smartwatches and augmented reality glasses,
which have ``significant latency and throughput requirements.'' These
wearable devices would face up to 96 dB of attenuation communicating
across the user's body. They also point to other use cases, such as
multiple peer-to-peer links, which would also greatly benefit from
higher power levels. They claim that their analysis shows that these
higher power levels are essential to meet the performance goals for
these and other envisioned use cases.
Federated Wireless supports the Commission's proposal to allow
greater power for VLP devices operating under the control of a
geofencing system, but instead of spending time and resources
developing a new system for geofencing, Federated Wireless advocates
relying on the currently authorized AFC systems. Federated Wireless
also encourages permitting GVP devices to operate at higher power than
the proposed 1 dBm/MHz EIRP PSD and 14 dBm EIRP because AFC systems are
``capable of offering the same level of protection to incumbents
regardless of the unlicensed device transmit power.''
The Wi-Fi Alliance points out that the computer simulations upon
which the Commission relied in permitting VLP operations ``show
virtually no impact on the microwave links even for VLP devices
operating at 1 dBm/MHz EIRP PSD.'' The Wi-Fi Alliance claims that VLP
devices will be predominantly used indoors, that their signals will be
attenuated by body loss when they are used outdoors, and that outdoor
VLP transmitters will operate far below the likely height of any 6 GHz
microwave facilities. Therefore, the Wi-Fi Alliance claims that
existing mitigation requirements are sufficient to protect microwave
operations from VLP devices operating at up to 1 dBm/MHz EIRP PSD and
14 dBm EIRP. The Wi-Fi Alliance contends that because the risk of
harmful interference from VLP devices operating at this power level
``is already extremely low,'' there is no benefit in imposing
geofencing requirements. The IEEE LAN/MAN Standards Committee (IEEE
LMSC) also does not believe that the Commission should require
geofencing if it increases the power level to 1 dBm/MHz EIRP PSD and 14
dBm EIRP because it effectively only would permit higher power for 20-
megahertz and 40-megathertz channels and would not result in increased
risk to incumbent services. IEEE LMSC claims that the incremental
improvement from this power increase does not justify mandating the
relatively complex geofencing mechanism and that developing this
geofencing mechanism will potentially delay this VLP mode from
deploying.
Cisco and HP Enterprise support slightly higher VLP power levels to
accommodate body loss, but caution that increasing VLP power needs to
be done so as to ensure that unlicensed LPI devices continue to coexist
among themselves and with VLP devices. According to Cisco and HP
Enterprise, the top request of enterprise customers is that Wi-Fi be
more predictable and reliable. Cisco and HP Enterprise explain that
interference to enterprise Wi-Fi means less spectrum availability,
which results in smaller channels with decreased capacity and increased
latency. They point out that ``[g]eofencing does not consider
coexistence with enterprise [Wi-Fi] networks'' and that ``[h]igher
power VLP . . . could interfere with other VLP use[s].'' They claim
that enterprise customers would like VLP to be coordinated by the
infrastructure when in the presence of LPI access points. Cisco and HP
state that the actual affect that VLP and GVP devices will have on
enterprise Wi-Fi networks is unknown, but that CableLabs is currently
studying that issue. Cisco and HP Enterprise recommend that the
Commission ``adopt reasonable limits on GVP/VLP while standards
develop''--i.e., ``slightly higher powered VLP to accommodate body
loss''--that improve coexistence among the different types of Wi-Fi
devices.
AT&T urges caution with respect to liberalizing the 6 GHz
unlicensed rules and expresses concern that the computer simulations on
which VLP device rules are based remain unfiled and untested. AT&T
suggests that the Commission ``gain some understanding of the impact of
actual, commercially deployed VLP devices before liberalizing the rules
by which they operate and, if it ultimately determines to do so, to act
with caution in a manner that is reversible.'' AT&T suggests that the
power limits for GVP devices ``should start conservatively, provide for
future modification, and be capped with reference to [the] risks
defined by geolocation parameters,'' with the power levels lower if the
Commission adopts a geofencing framework that carries substantial risk
to incumbent microwave receivers. AT&T is concerned that the proposal
of 1 dBm/
[[Page 9143]]
MHz EIRP PSD limit ``does not appear to be a conservative starting
point'' and, ``[e]ven more dire, the 6 GHz Second FNPRM seeks comment
on increasing the [maximum] EIRP to 21 dBm.'' AT&T complains that ``the
[GVP] proponents' response to the 6 GHz Second FNPRM amounts to
platitudes that geofencing . . . will self-evidently protect incumbents
and the Commissions needs not worry because their prior studies . . .
should nonetheless carry the day.'' AT&T claims that ``no geofencing
advocate has advanced a proposal for geofencing that allows incumbents
to rationally evaluate the potential for harmful interference.'' AT&T
demands that before the Commission authorizes GVP operations, the
record should contain proposed rules that cover such topics as location
determination and accuracy, how geofencing boundaries will be
implemented, additive interference, the geofencing model (geofencing
system architecture), GVP device elevation, database and geofence
reauthorization intervals, and an exclusion zone buffer to account for
mobility.
Evergy cautions that the Commission ``should hold off on further
expanding unlicensed operations in the 6 GHz band until enough real-
world experience has occurred to gain the confidence of incumbents in
the utility industry.'' Evergy is concerned that unlicensed devices
will raise the noise floor and result in harmful interference to
incumbent licensed operations. Evergy cautions that if harmful
interference occurs, its ``existing mission-critical systems may become
unreliable and inoperable while its engineers engage in . . . [the]
extremely difficult, if not impossible, task'' of identifying the
responsible unlicensed device(s). Evergy describes the proposed 1 dBm/
MHz EIRP PSD as ``a dramatic increase in power that poses significant
risk to incumbent licensees'' and urges the Commission to reject this
proposal as well as the request by GVP advocates for maximum power
levels of 21 dBm EIRP and 8 dBm/MHz EIRP PSD. Evergy asks that the
Commission ensures that any geofencing solution protect microwave links
commensurate with the protection provided by the AFC system.
The American Petroleum Institute (API) does not support permitting
VLP devices to operate at 1 dBm/MHz EIRP PSD until more field data on
VLP devices and interference is collected, which it predicts would take
two years or more. Provided data is collected over the proper time
frame and the results show VLP devices are operating without impacting
incumbents, API claims that the proposed geofencing system allowing GVP
devices to operate at up to 1 dBm/MHz EIRP PSD and 14 dBm EIRP appears
to have merit. The Utilities Technology Council and the Edison Electric
Institute (UTC/EEI) joint comments advise the Commission to ``refrain
from further expanding unlicensed operations in the 6 GHz band'' until
it better understands the interference environment from currently
authorized 6 GHz unlicensed devices. The Association of Public-Safety
Communications Officials, International (APCO), noting the rules for
that VLP devices have only recently been implemented, advises the
Commission to let ``[r]eal-world operational experience and testing . .
. guide any future decision-making rather than risk essential public
safety communications networks with theoretical models and lab testing
alone.''
The Electric Power Research Institute (EPRI) states that if VLP
devices ``[are] allowed to operate at 1 dBm/MHz [EIRP] PSD, then it is
imperative that the method used to prevent operation in areas with
elevated risk of harmful interference be infallible.'' EPRI claims that
its research shows that even at the -5 dBm/MHz EIRP PSD level at which
VLP devices operate, a scheme to prevent VLP devices from operating co-
channel in a microwave receiver's main beamwidth is necessary to
prevent harmful interference and that exclusion zones could be an
effective method to protect these sites provided the propagation models
align with the findings from real-world testing.
Discussion. The Commission is adopting rules to permit GVP devices
to operate in the U-NII-5 and U-NII-7 portions of the 6 GHz band at up
to 11 dBm/MHz EIRP PSD and 24 dBm EIRP while under the control of a
geofencing system. As discussed in more detail in this document, the
geofencing system must comply with various requirements to prevent GVP
operations at locations where they may cause a significant risk of
harmful interference to licensed incumbent services that share the 6
GHz band. The geofencing system will use the same propagation models
and protection criteria that are employed by AFC systems to calculate
exclusion zones in which the GVP access points will not be permitted to
operate co-channel with a microwave receiver. The geofencing system
will also prevent GVP access points from operating near certain radio
astronomy observatories. The GVP access points will be required to have
a geolocation capability to determine when they enter an exclusion zone
and must adjust their operating frequency, if necessary, to meet this
condition. GVP client devices, which will not be required to have a
geolocation capability, will operate only under the control of a GVP
access point at 6 dB less than the controlling access point's
authorized power.
The Commission adopts the 11 dBm/MHz EIRP PSD and 24 dBm EIRP power
levels rather than the 1 dBm/MHz EIRP PSD and 14 dBm EIRP power levels
proposed in the 6 GHz Second FNPRM for several reasons. First, the
geofencing systems will be equally effective in preventing a
significant risk of harmful interference at the higher power levels
because the size of the exclusion zones will increase to account for
the higher power--i.e., the size of the exclusion zones scales with the
power level. Second, the Commission agrees with commenters who opine
that permitting higher power levels than those proposed in the 6 GHz
Second FNPRM provides a stronger incentive for manufacturers to invest
in geofencing systems and GVP devices. Moreover, the Commission
recognizes that adopting the proposed GVP power levels, which are only
an incremental power increase to the VLP power levels, may not convince
industry to undertake the expenses associated with developing this new
class of devices. Lastly, the Commission believes that 11 dBm/MHz EIRP
PSD and 24 dBm EIRP are necessary for GVP access points to deliver the
required reliability and performance for body worn applications, as
Apple and Meta point out. According to measurements conducted by the
Wireless Research Center of North Carolina, which examined the
attenuation between two body worn devices for six test subjects, body
attenuation can range from 28 to 96 dB. Considering the high level of
signal attenuation that must be overcome between body-worn devices, the
Commission concludes that the higher power levels it's permitting are
appropriate.
Commenters agree that permitting higher power levels will enable
more versatile GVP devices to be developed and result in a wide variety
of innovative products. As Apple, Broadcom et al., point out, the
higher PSD level will be particularly useful for applications that rely
on narrow channels such as high bitrate audio and control signaling
while the higher maximum power will benefit data-intensive tasks in
applications such as artificial reality/virtual reality, automotive
technologies, screen mirroring, hotspots, and indoor location and
navigation. Adopting the higher power levels requested by industry with
a geofencing requirement provides more versatility to encourage
innovative uses
[[Page 9144]]
and incentivize investment without increasing the harmful interference
risk to incumbent users. The Commission also points out that even
though it's permitting up to 11 dBm/MHz PSD and 24 dBm EIRP levels, the
Commission expects the majority of devices to operate below these
maximum levels most of the time. For many reasons, including to
increase battery life, portable devices generally operate at the
minimum power level necessary to close the link. In addition, the
Commission notes that Apple and Meta's filing shows that body
attenuation is highly variable based on individual factors; the maximum
power is only needed for the extreme cases when body attenuation is at
its highest. Thus, the higher power levels the Commission is allowing
combined with a geofencing system that scales exclusion zones to the
power level provides maximum flexibility for the development of
versatile devices to provide new applications to the public while
continuing to protect incumbent services from a significant risk of
harmful interference.
The Commission declines to adopt the two-power level model
suggested by Apple. The Commission appreciates the desire to simplify
geofencing system implementation, but believe this decision is best
driven by geofencing system providers based on intended customers and
applications or through industry consensus within a standards process.
The rules the Commission adopts simply define maximum PSD and EIRP and
permit geofencing system providers to determine whether to calculate a
single exclusion zone based on the maximum power or to calculate
multiple exclusion zones indexed for lower power levels. Thus,
geofencing system providers can determine the proper tradeoff between
the flexibility and complexity associated with calculating a single or
multiple exclusion zones.
The Commission also does not find it appropriate to limit the power
available to GVP devices to protect enterprise LPI Wi-Fi devices, as
suggested by Cisco and HP Enterprise. 6 GHz band unlicensed devices are
expected to share the band with other unlicensed devices. The operators
of enterprise Wi-Fi networks have no basis to expect that they can
manage use of the 6 GHz band spectrum solely for their benefit. One of
the Commission's goals for expanding unlicensed use in the 6 GHz bands
is to encourage the development of innovative consumer devices. By
increasing the power available to VLP devices that employ geofencing,
the Commission will enable exciting new applications, such as body-worn
devices for augmented reality/virtual reality, as well as provide for
higher data rates for existing uses, such as Wi-Fi hotspots. The
Commission does not believe that it would be in the public interest to
forego these new applications to potentially prevent harmful
interference from occurring to other unlicensed device users. The new
applications and higher data rates will be widely available to all
consumers and businesses. The Commission believes this is preferrable
to the alternative of restricting the capabilities of GVP devices by
limiting their power in order to, in effect, permit enterprises to
exclusively use the shared 6 GHz band spectrum within their facilities.
Moreover, the Commission notes that its rules contain provisions
designed to promote coexistence among all devices operating in the 6
GHz bands. For example, GVP devices will need to comply with the same
contention-based protocol requirements already in place for LPI and VLP
devices and the dynamic transmit power control requirement in place for
VLP devices.
The Commission declines to delay adopting GVP rules in order to
collect more data or conduct testing, as suggested by API, UTC/EEI,
APCO, Evergy, and AT&T. The Commission also sees no reason to adopt the
incremental approach of initially adopting a lower GVP power level and
potentially increasing it after the Commission gains more experience
with GVP operations. The Commission's rules for AFC-enabled standard-
power devices were adopted in 2020, (85 FR 31390, May 26, 2020), and
AFC systems have been approved for commercial operation since February
2024. The Commission has not received any interference complaints
related to 6 GHz standard-power devices operating under the control of
AFC systems. Because GVP geofencing systems will employ the same
propagation models and determine exclusion zones using the same I/N
threshold as the AFC systems, the Commission is confident that the
geofencing systems will be equally effective at preventing a
significant risk of harmful interference. Also, in the unlikely event
that harmful interference occurs, the Commission will require
geofencing systems to adjust any or all exclusion zones. Thus, the
rules contain an effective mitigation strategy should harmful
interference occur.
The Commission is unpersuaded by Evergy's concerns regarding
increasing the noise floor or causing harmful interference to microwave
receivers. The geofencing system will prevent operation of GVP access
points and associated client devices at locations where they present a
risk of causing harmful interference to microwave receivers. The
Commission notes that Evergy has not presented any technical analysis
indicating that such harmful interference will occur in practice or
that GVP devices operating in conjunction with a geofencing system will
raise the noise floor. The Commission's experience with AFC systems and
the fact that the exclusion zones can be adjusted, if necessary,
indicate that harmful interference is unlikely to be an issue and that
if any interference issues do arise, they can be addressed by the
Commission. As to EPRI's contention that any method used to prevent VLP
device operation in areas with elevated interference risk must be
``infallible,'' we acknowledge that no spectrum management system is
infallible. However, based on past experience with using databases to
effect spectrum management opportunities, such as with the AFC systems
and the spectrum access systems (SAS) used to manage access to the
3550-3700 MHz band in the Citizens Broadband Radio Service, the
Commission believes that the geofencing systems that its rules are
enabling will permit GVP operation without posing a significant risk of
harmful interference.
The Commission disagrees with AT&T that the lack of a specific
proposal by GVP advocates prevented incumbents from rationally
evaluating the potential for harmful interference. The rules the
Commission is adopting closely mirror its proposal in the 6 GHz Second
FNPRM and require GVP devices to operate pursuant to a geofencing
system that will be based on the same propagation models as used for
the AFC systems. The 6 GHz Second FNPRM sufficiently discussed the
topics that AT&T claims must be included in a serious proposed set of
GVP rules.
The Commission is not increasing the general (i.e., non-geofenced)
VLP PSD to 1 dBm/MHz EIRP, as suggested by the Wi-Fi Alliance and the
IEEE LMSC. The 6 GHz Second FNPRM explicitly declined to seek comment
on modifying the VLP rules for devices operating without a geofencing
system except for some aspects of the out-of-band emission limits.
Thus, any consideration of higher power for non-geofenced VLP devices
is beyond the scope of the FCC's proceeding.
Finally, AT&T questions the computer simulations on which the
Commission relied when adopting the VLP device rules. However, the
Commission is not relying on those computer simulation results in
reaching our decision to permit GVP operations. Instead, the
[[Page 9145]]
Commission bases its decision to permit GVP on the adoption of rules
requiring the use of a geofencing system to prevent any significant
risk of harmful interference. Therefore, the veracity of the
simulations the Commission relied on when authorizing VLP devices is
not relevant to the Commission's decision here permitting GVP
operations.
GVP Client Device Power
The 6 GHz Second FNPRM proposed to require client devices operating
under the control of a GVP access point to transmit only on channels
determined by that GVP access point. Under this proposal, client
devices would not be required to directly obtain or calculate exclusion
zones. The 6 GHz Second FNPRM proposed that client devices operating
under the control of a GVP access point be permitted to operate at the
same power level as the GVP access point.
AT&T expresses concern that the 6 GHz Second FNPRM proposed to
permit client devices connected to GVP access points to operate at the
same power as the GVP access point, even though only the GVP access
points will be subject to geolocation and geofencing requirements. AT&T
calls this a ``significant and unexplained departure from the
requirement'' for standard-power and LPI operations that client devices
operate at power levels at least 6 dB less than the associated access
points. AT&T suggests that if the Commission does not require GVP
client devices to similarly operate at lower power levels, the
exclusion zones should be extended by 365 meters, the range over which
AT&T claims that two GVP devices could communicate.
Apple, Broadcom et al. suggest that the Commission's rationale for
adopting lower power limits for standard-power and LPI client devices
does not apply to GVP devices. Apple, Broadcom et al., note that the
Commission mandated lower power for standard-power and LPI client
devices ``as a precaution against the theoretical scenario that a
client device could operate in a location with a substantially
different interference potential compared to its associated standard-
power [access point].'' Apple, Broadcom et al. claim that scenario will
not occur for GVP client devices because they ``must operate in close
proximity [to their access point] due to their lower power levels
relative to standard power [access points].'' Apple, Broadcom et al.
further explain that the power level for LPI client devices was
specifically lowered to prevent outdoor use, an issue that is not
relevant for GVP client devices, which would be allowed to operate
outdoors.
Apple supports the Commission's proposal to authorize the same
power levels for GVP access points and client devices because the
devices will rely on symmetrical bi-directional communication. Apple
suggests that if the Commission decides to adjust the size of the
exclusion zones determined by the geofencing system to account for the
potential separation distance between a GVP access point and client
device, ``expanding the exclusion zones by 75 meters would be a very
conservative approach,'' as demonstrated by data presented by Apple and
Meta. The Apple and Meta data show the separation distance that can be
achieved between GVP access points and client devices when operating a
communication link at different Wi-Fi modulation and coding schemes
(MCS) in urban and suburban areas. These calculations were based on
operation with 21 dBm EIRP, 4 dB of body loss, 0 dBi antenna gain, a
transmit frequency of 6.5 GHz, and the use of the propagation models
specified in the Commission's rules for AFC operation. This data
illustrates that as the MCS level increases the GVP access points and
client devices must be closer together to successfully communicate.
Apple and Meta maintain that these calculations show that ``a 75-meter
buffer would more than account for the potential distance between a
[GVP access point] and client [device] . . . because this would be
larger than the maximum separation distance established using AFC
modeling for devices operating at MCS 4.'' Apple and Meta claim that
``[GVP] devices are likely to overwhelmingly operate at MCS 4 and
above'' because ``[o]peration at MCS 1 would not support the throughput
requirements needed for this class of devices, which will enable
[augmented reality], video, and other high-throughput applications.''
They also maintain that ``in the real world, [GVP] devices will rarely,
if ever, be separated by 75 meters'' because they ``may not be fixed,
must be workable at far lower power than standard Wi-Fi, and include a
geolocation-capable [access point].'' Apple and Meta note that GVP
devices ``[t]ypically will be body-worn devices that operate with
negligible separation distances.'' Apple and Meta also claim that
AT&T's suggested 365-meter buffer distance cannot be replicated and
that AT&T relies on unrealistic assumptions, such as using only the
free-space propagation model.
Recently, Apple and Meta have implicitly supported a 6 dB power
differential between GVP access points and associated client devices by
advocating that maximum authorized power levels of at least 11 dBm/MHz
PSD and 24 dBm EIRP for GVP access points and 5 dBm/MHz PSD and 18 dBm
EIRP for GVP client devices are essential for adequate reliability and
performance for GVP use cases.
Discussion. The Commission is adopting GVP access point power
levels that are higher than were proposed in the 6 GHz Second FNPRM--up
to 11 dBm/MHz EIRP PSD and 24 dBm EIRP instead of the proposed 1 dBm/
MHz EIRP PSD and 14 dBm EIRP. At these higher power levels, it is
possible for client devices to operate at distances farther from the
controlling GVP access point than anticipated under the Commission's
proposal. Although many potential GVP applications, such as body-worn
devices for augmented reality/virtual reality, will involve access
points and client devices located on the same person, other
applications, such as a GVP mobile hotspot, would likely involve client
devices that are distant from the access point. Consequently, a client
device operating at the same power as its controlling GVP access point
could be located within an exclusion zone even when the GVP access
point is safely outside of the exclusion zone. Therefore, consistent
with existing 6 GHz client device rules, the Commission will require
client devices under the control of a GVP access point to operate at
power levels at least 6 dB less than the power level determined by the
geofencing system for the associated GVP access point. Because the
Commission is implementing this power reduction requirement for GVP
client devices, the Commission declines to extend the exclusion zone
boundaries, as AT&T suggests.
Apple, Broadcom et al. provide no rationale to support its claim
that GVP client devices must operate in close proximity to GVP access
points. While Apple, Broadcom et al. are correct that one of the
motivations for the 6 dB power differential between LPI access points
and their associated client devices was to limit the client devices to
indoor operation, client devices connected to standard-power access
points are also restricted to 6 dB less power than their associated
access point and such access points and client devices are not limited
to indoor operation. This illustrates that when adopting the rules for
standard-power devices the Commission believed that it is necessary to
impose a 6 dB power difference between access points and client devices
to prevent the client devices from operating too close to
[[Page 9146]]
microwave receivers even when the associated access point is operating
under the control of an AFC system. The Commission continues to hold to
that reasoning and reach the same conclusion for GVP devices. In
addition, Apple provides no basis for contending that GVP devices will
rely on symmetrical bi-directional communication. Other 6 GHz
unlicensed devices such as standard-power and LPI devices function with
a 6 dB power differential between access points and client devices and
the Commission sees no basis for concluding that GVP devices cannot
also be designed to account for this power difference.
The Commission finds that providing 6 dB lower power for GVP client
devices is a superior approach for compensating for the separation
distance between GVP access points and client devices than adding a 75-
meter buffer to the exclusion zone boundaries, as suggested by Apple
and Meta. The 75-meter buffer size is based on the assumption that at
least MCS 4 will always be necessary for these devices. While this may
be the case for the augmented-reality glasses and wristband
electromyography technology that are the subject of Apple and Meta's
presentation, the Commission is not limiting GVP devices to particular
technologies or applications. GVP devices operating under the rules the
Commission is adopting are expected to operate at a range of MCS levels
as needed for different applications and will be able to employ
technologies other than Wi-Fi. Consequently, the Commission cannot
conclude that GVP access points and client devices will always be
limited to a 75-meter separation distance. Applying the same 6 dB power
level differential between access points and client devices as the
Commission have used for other types 6 GHz unlicensed devices is a more
straightforward approach to protecting licensed operations that share
the 6 GHz band, while also enabling GVP client devices to operate at
the power levels that Apple and Meta state are necessary to ensure
reliable communications. This approach also maintains the coexistence
scheme already in place to protect incumbents from a significant risk
of harmful interference.
The Commission does not believe that imposing a 6 dB power
differential between GVP access points and associated client devices
will hinder the usefulness of GVP devices. As noted above, Apple and
Meta have advocated that GVP client devices should have a maximum
permitted power level of at least 18 dBm and 5 dBm/MHz to support the
envisioned use cases, such as body-worn devices for augmented reality
applications and multiple peer-to-peer links. While Apple, Broadcom et
al. have indicated that they support 8 dBm/MHz EIRP PSD and 21 dBm EIRP
power levels and also advocate for no power differential between GVP
assess points and client devices, they have not indicated that limiting
client devices to 3 dB below these power levels will hinder the
implementation of particular use cases. Therefore, the Commission has
no reason to conclude that the power limits its establishing for client
devices under the control of GVP access points will inhibit the
usefulness of GVP devices.
Under the rules the Commission is adopting, GVP client devices are
limited to a maximum of 5 dBm/MHz EIRP PSD and 18 dBm EIRP. In
addition, for GVP access points operating within an exclusion zone and
pursuant to geofencing instructions limiting power below the maximum
permitted, associated client devices will similarly be required to
reduce power such that they are at least 6 dB less than the maximum
power permitted for the GVP access point. For example, if a GVP access
point is operating in an exclusion zone and limited by the geofencing
system to 1 dBm/MHz EIRP PSD and 14 dBm EIRP, an associated client
device will be limited to -5 dBm/MHz EIRP PSD and 8 dBm EIRP. However,
if a GVP access point transmits at less than its maximum permitted
power level, the maximum power for the client device is determined by
subtracting 6 dB from the access points maximum permitted power, not by
subtracting 6 dB from the access points transmit power. For example, if
a GVP access point that is operating outside of any exclusion zone
transmits at 5 dBm/MHz PSD and 18 dBm EIRP, an associated client device
could transmit at this same power level because the maximum permitted
power level of the access point is 11 dBm/MHz PSD and 24 dBm EIRP.
GVP Operations in U-NII-6 and U-NII-8
In the 6 GHz Second FNPRM, the Commission proposed that geofencing
systems protect BAS and CARS operations in the U-NII-6 and U-NII-8
bands. The Commission noted that both the U-NII-6 and U-NII-8 bands are
used by mobile broadcast auxiliary services, including outdoor
electronic news gathering (ENG) trucks and low power short range
devices, such as portable cameras and microphones. Low Power Auxiliary
Stations, which are licensed in portions of the U-NII-8 band, operate
on an itinerant basis and transmit over distances of approximately 100
meters for uses such as wireless microphones, cue and control
communications, and TV camera synchronization signals. ENG trucks
transmit video programming, generally using telescoping directional
antennas that are oriented toward a central receive site from remote
sites, such as the location of news or sporting events, to a central
receive site. The Commission proposed that the geofencing systems
protect the BAS and CARS operations using the same propagation models,
interference protection criterion, and body loss assumptions as used to
protect microwave receivers in the U-NII-5 and U-NII-7 bands.
Due to the steerable nature of the central receive antennas, the
Commission asked if exclusion zones surrounding central receive sites
need to be circular to ensure protection in all directions, or could
they be only part of a circle, i.e., less than 360 degrees. The
Commission noted that BAS and CARS operations are typically licensed
for the entire band(s) in which they operate (i.e., U-NII-6, U-NII-8,
or both) and asked whether GVP devices should avoid operation across
the entire band that a BAS/CARS site receives within the exclusion
zones. The Commission sought comment on whether there are ways to
reduce the size of the exclusion zones to protect BAS and CARS receive
sites, limit the number of frequencies excluded within those zones, or
limit receive site protection to only the specific times when they are
in use. More specifically, the Commission asked whether BAS and CARS
users should be required to notify a geofencing system of their ENG
operations, and for the geofencing systems to incorporate a push
notification feature or similar functionality to provide information
(e.g., actual operating locations and frequency usage, on a near real-
time basis) to GVP devices so that the exclusion zones in the U-NII-6
and U-NII-8 bands can be tailored to actual usage rather than all
possible usage areas. The Commission noted that if it were to adopt a
push notification or similar approach to protect BAS/CARS based on
usage, there would be a need for one or more centralized systems to
register BAS/CARS usage and provide the information to geofencing
systems.
The Commission proposed that low power short range BAS and CARS
devices, such as portable cameras and microphones, and Low Power
Auxiliary stations be protected from harmful interference by a
combination of a required contention-based protocol and
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the low probability of a GVP device operating on the same channel in a
nearby location. The Commission explained that the sensing function
associated with the contention-based protocol, along with the low
probability for co-channel operation, is sufficient to ensure that GVP
devices detect nearby mobile BAS operations and avoid transmitting co-
channel to protect those operations from harmful interference.
Apple, Broadcom et al. point to a computer simulation they
submitted prior to the issuance of the 6 GHz Second FNPRM as evidence
that harmful interference will not occur to ENG receive sites from GVP
operations at 21 dBm EIRP. This simulation examined two ENG receive
sites at Cowles Mountain, San Diego, CA, and the Old Post Office in
Washington, DC. The simulations analyzed mobile links from ENG trucks
to BAS central receive sites for a total of six links per site. The
simulations purport to show that both sites had a close to zero percent
probability of experiencing an I/N higher than -6 dB due to VLP devices
operating at 21 dBm. While Apple, Broadcom et al. claim the record
shows there will be an insignificant risk of harmful interference when
GVP operates at 21 dBm EIRP, they ``support the Commission's belt-and-
suspenders use of geofencing for this GVP device class.'' They note
that adopting a contention-based protocol requirement and the
opportunity for broadcasters to report on ENG link locations will
further diminish the risk of harmful interference to ENG incumbent
licensees.
NAB contends that the Commission's proposal to protect mobile
operations using exclusion zones around registered ENG central receive
sites is based on an incomplete view of how this spectrum is used. It
points out that ``[w]hile transmission from a mobile ENG truck to a
central receive site is a common way that licensed users of this
spectrum operate,'' ``[b]roadcasters make use of this spectrum in
myriad ways when covering newsworthy events, including from camera-back
transmitters to temporary receivers mounted on trucks that can operate
nationwide.'' NAB claims that the proposal for BAS users to provide
operating locations and frequencies to a database administrator would
``add[ ] significant burden and delay to the newsgathering process''
and require ``untold expense to implement a system to capture this
information.'' NAB also criticizes the computer simulation upon which
Apple, Broadcom et al. rely, claiming that the analysis showing
absolutely no interference to ENG receivers is plainly unreasonable
because many hypothetical VLP transmitter locations near an ENG receive
antenna would present a signal exceeding a -6 dB I/N level.
Discussion. The Commission defers adoption of rules to permit GVP
operation in the U-NII-6 and U-NII-8 bands because it does not believe
that the record currently contains sufficient details to adopt
geofencing that will efficiently manage spectrum while protecting
mobile BAS and CARS operations. Because news events can occur anywhere
with little notice, a geofencing system that is based on the actual
location and directionality of the links between ENG truck transmitters
and the central receive sites will require updated information on the
locations of ENG truck transmitters. If the ENG operations are not
tracked in a centralized database, the geofencing systems will have to
protect the ENG receivers over a 360-degreee radius at all times. This
large area will need to be protected across the entire U-NII-6 and U-
NII-8 bands because BAS and CARS licenses typically permit
transmissions across the entire bands. Because ENG news gathering is
conducted by broadcasters throughout the nation, establishing exclusion
zones at every ENG central receive site that covers the entire U-NII-6
and U-NII-8 bands will remove a tremendous amount of spectrum from use
by GVP devices. Hence, to efficiently manage access to this spectrum
the Commission finds that it should consider how geofencing systems can
be designed to use information on actual ENG use to quickly update the
exclusion zones governing GVP device use.
While Apple, Broadcom et al. support the use of geofencing systems
for GVP devices operating in the U-NII-6 and U-NII-8 band and contend
that NAB has not substantiated its claim that providing real-time
information on BAS/CARS use would be a burden to newsgathering
operations, they have not provided any details on how geofencing
systems would collect BAS/CARS usage information and manage GVP device
spectrum use. For the Commission to adopt rules for geofencing systems
that use real-time information on BAS/CARS use, the Commission would
have to address many issues such as: How would the information on BAS/
CARS use be collected? Who would collect this information? What
specific information would be collected? How would the information be
propagated to the various geofencing systems? How would updated
exclusion zones based on this information be pushed to the GVP access
points? How quickly would the GVP access points need to adjust their
spectrum use as BAS/CARS spectrum use changes? Given the lack of record
on how this process would work in practice, the Commission does not
believe that it has sufficient information to adopt rules for
geofencing systems for the U-NII-6 and U-NII-8 bands. In adopting rules
to permit GVP device operations in the U-NII-5 and U-NII-7 bands while
deferring consideration of operations in the U-NII-6 and U-NII-8 bands,
the Commission is following the same path it used to adopt rules for
VLP devices. In the 2023 6 GHz Second Order, the Commission adopted
rules to permit VLP device operation in U-NII-5 and U-NII-7. In 2024,
after obtaining a more robust record, the Commission expanded VLP
operations to the U-NII-6 and U-NII-8 bands in the 6 GHz Third Order
(90 FR 11373, March 6, 2025).
Geofencing System Architecture
In the 6 GHz Second FNPRM the Commission proposed to provide
manufacturers with flexibility to design appropriate geofencing systems
for different equipment use cases rather than mandate a specific
geofencing system architecture and provided three examples. A first
example architecture could have a centralized geofencing system
calculate exclusion zones based on information obtained from Commission
databases, e.g., the Universal Licensing System (ULS), as well the
Commission's rules. A GVP access point would contact the centralized
geofencing system to download exclusion zones and then manage its
spectrum use based on the downloaded information. A second example
architecture could have a GVP access point regularly send its location
to a centralized geofencing system, which would then inform the access
point as to the channels it may use. This second example architecture
would use the same methodology as the existing AFC systems that manage
standard-power access point spectrum access with the added requirement
to account for the inherent mobility associated with GVP access points.
A third example architecture could integrate the geofencing system
within a GVP access point. A GVP access point would obtain local
licensing data by downloading information from an external source. The
GVP device would need to contain software necessary to use that data to
independently determine exclusion zones and manage its spectrum use.
The first and second examples are categorized as ``centralized''
architectures because they rely on a central server to perform the
calculations necessary to implement the
[[Page 9148]]
geofenced exclusion zones, while the last is a ``distributed
architecture'' in which the calculations are performed by each GVP
access point. The Commission proposed to permit either a distributed or
centralized architecture. The Commission also sought comment on whether
it should provide flexibility for the geofencing system implementations
or specify a single approach.
AT&T suggests that the Commission require a geofencing architecture
where the GVP device downloads keyhole-shaped geofenced exclusion zones
from a central server because such a system would be simpler than the
Commission's other two example architectures. This suggested
architecture is a specific example of the first example architecture
which uses simplified exclusion zone boundaries rather than permitting
more complex exclusion zones determined by propagation models
consistent with the AFC systems as the Commission has proposed. AT&T
notes that the simplified approach of the first example architecture
would ``reduce[ ] the complexity and storage requirements of those
[GVP] devices.'' By contrast, AT&T claims that the Commission's second
example architecture, in all practicality, would revert to the existing
AFC system and result in overly complex exclusion zones. AT&T also
advises the Commission not to authorize a distributed architecture,
i.e., the Commission's third example architecture. According to AT&T, a
distributed architecture would effectively require each device to be
its own AFC system but without the controls in place for AFC systems,
such as the standards-based interference calculation, AFC system public
validation through trials, and a common interference reporting system.
AT&T claims that AFC system and device implementation variations would
render device certification untenable. AT&T argues that permitting
these types of devices would ``impose[ ] massive burdens on [fixed
microwave] incumbents to continually monitor every VLP device
application and conduct assessments to determine if a multiplicity of
self-coordinating devices using proprietary mechanisms will actually
protect [fixed microwave] incumbents. Evergy advocates that the
Commission require a centralized architecture to calculate exclusion
zones to ensure licensed incumbents are protected in a consistent and
predictable manner. UTC/EEI also favor a centralized architecture,
noting that a distributed framework would not be as effective and would
pose a greater interference risk to incumbents.
Apple, Broadcom et al. explain that the Commission's proposal to
``allow[ ] both centralized and distributed geofencing systems affords
device manufacturers sufficient flexibility to facilitate higher-power
operations while still providing robust protections for incumbent
operators.'' According to Apple, Broadcom et al., ``AT&T's opposition
to the Commission's proposal fails to recognize that (1) the AFC rules
prohibit mobile devices and (2) the Commission's geofencing proposal
has several critical benefits compared to an AFC--energy efficiency,
consumer privacy, and flexibility.'' Apple, Broadcom et al. claim that
the fundamental difference between what the Commission proposes and
AT&T's proposal is that the Commission's proposal facilitates mobile
operations. They note that the AFC rules prohibit mobile operations and
that the Commission's proposal is ``simple enough to facilitate mobile
operations without imposing unnecessary device or AFC system
complexity.'' Apple, Broadcom et al. also claim that AT&T's proposal
``would require frequent AFC system queries, which would drain
consumers' batteries'' and would compromise consumer privacy due to the
need to constantly transmit the access point's location to third
parties. Apple, Broadcom et al. also claim that the Commission's
proposal will support GVP technology adoption for a broad range of
applications. Apple, Broadcom et al. also disagree with AT&T's claim
that consumer devices will not be capable of implementing a distributed
architecture. They explain that device manufacturers can choose which
approach is best for its device; noting that the Commission's proposal
allows more capable devices to use the distributed approach.
Comsearch recommends that the Commission allow flexibility for the
geofencing architecture, noting that the GVP device use case should
determine which architecture is most feasible. According to Comsearch,
if a centralized approach, such as the current AFC systems, is used,
the need for a mobile device to keep the centralized system informed of
its location, direction, and velocity ``would substantially complicate
message exchange and spectrum availability calculations'' compared to
AFC systems. However, Comsearch states that a centralized approach,
such as an AFC system, would be more feasible for stationary GVP
devices.
Federated Wireless urges the Commission to ``adapt the currently
authorized AFC systems for the new [GVP] class'' rather than certifying
a novel system. According to Federated Wireless, ``[t]he information
that AFC systems currently provide to [s]tandard [p]ower devices in the
6 GHz band is identical to what would be needed to allow higher-power
[GVP] devices to access those frequencies.'' In order to account for
GVP device mobility, Federated Wireless suggests that information on
channel availability and power levels could be calculated for a
predefined area, with the device only needing to check-in with the AFC
system again if it moves outside that area. Federated Wireless
recommends that ``AFC system operators work with [GVP] device
manufacturers to specify how this interaction would work in practice
and to address other challenges that are specific to [GVP] devices,
including battery power consumption and privacy.'' Federated Wireless
also agrees with other commenters, such as Comsearch, that the
Commission should accommodate any geofencing system architecture that
allows GVP devices to operate without causing harmful interference to
incumbents. API claims that the geofencing calculation is best done by
an AFC system rather than by a separate geofencing provider.
Discussion. The Commission will require geofencing systems to use a
centralized architecture to control GVP access points. Although the
Commission sought comment on also permitting a distributed geofencing
architecture, the Commission finds that it is appropriate to limit
geofencing systems to a centralized architecture because of concerns
that it would be difficult to test a distributed architecture
geofencing system and that such a system would make it difficult to
address any instance of harmful interference, should it occur. As AT&T
notes, a distributed geofencing architecture would essentially permit
each device to act as its own AFC system, but without any of the
controls placed on AFC systems. AFC systems are only authorized after
extensive lab testing using industry developed test vectors and a
public trial where interested parties have the opportunity to examine
AFC system outputs for specific locations. Because each GVP access
point in a distributed geofencing system would need to calculate the
exclusion zones, each GVP access point model would need to be tested to
verify compliance with the Commission's exclusion zone rules. As AT&T
states, the need to monitor every VLP device application and conduct
sophisticated assessments on those devices would
[[Page 9149]]
impose massive burdens on primary microwave incumbents to determine
whether the VLP device adequately protects those systems. Although AT&T
raises concerns with testing the operation of distributed geofencing
systems in its comments, no commenters provide any suggestions on how
such systems may be tested. Given the importance that the Commission
places on preventing harmful interference from occurring to licensed
incumbents and the need to verify through adequate testing the proper
functioning of the geofencing systems, the Commission will not permit
use of a distributed geofencing architecture.
In the 6 GHz Second FNPRM, the Commission proposed that each
geofencing system operator for centralized systems establish and follow
protocols to comply with Commission instructions regarding enforcement
actions and to adjust exclusion zones, as necessary, to more accurately
reflect the potential for harmful interference. The Commission is
adopting these requirements for centralized geofencing systems. These
provisions enable the Commission to take action in the unlikely event
that a GVP device causes harmful interference to a licensed incumbent.
Under a centralized architecture, the Commission can simply issue
necessary instructions to the approved geofencing systems to mitigate
any harmful interference instances by either eliminating certain
devices from operating as GVP devices or to adjust exclusion zones.
However, it is not apparent, and commenters have not addressed, how
these requirements can be satisfied for a distributed geofencing
architecture where each GVP access point may not have regular contact
with a database to receive such instructions in a timely manner. This
is another reason the Commission is not permitting a distributed
geofencing architecture.
While the Commission noted two examples of centralized geofencing
architectures, the Commission is providing flexibility for geofencing
administrators to implement various centralized architectures. The
Commission's approach will permit geofencing systems to leverage
existing AFC systems which could accelerate the time for GVP technology
becoming commercially available. However, the Commission will not
require that geofencing systems be based on the currently authorized
AFC systems, as Federated Wireless and API suggest, because this may
discourage innovation and limit the number of geofencing systems that
are developed with no apparent benefit. So long as a geofencing system
uses a centralized architecture and meets our other requirements, the
Commission will not restrict administrators from implementing their
preferred method. The Commission believes that this flexible approach
will lead to GVP devices that meet a wide variety of use cases. The
Commission believes that the first example architecture, where GVP
access points determine whether they are in an exclusion zone by
downloading information describing those zones from a centralized
geofencing system, may be most likely to be deployed, but the
Commission will not require use of this specific architecture. Apple,
Broadcom et al. argue that AT&T's opposition to the Commission's
proposal to permit flexibility in the geofencing architecture fails to
recognize the benefits that the proposal has compared to requiring an
AFC system, such as energy efficiency, consumer privacy, and
flexibility. While the Commission is not adopting the proposal to
permit use of a distributed architecture, the flexibility that we are
providing to permit use of any type of centralized architecture
provides these benefits. Under the first example architecture, only
infrequent communication is needed between the GVP access point and
geofencing server because the GVP access point can download exclusion
zones for a large area, thereby enhancing device battery life. Because
only infrequent communication will be required, use of the first
example architecture will not substantially complicate message exchange
and spectrum availability calculations as Comsearch implies. The first
example architecture will also protect consumer privacy because the
device does not need to inform the database as it changes position. The
rules the Commission are adopting provide the flexibility to use any
type of centralized architecture, which should provide device
manufacturers with the flexibility to work with geofencing system
providers and design appropriate geofencing systems for different use
cases.
Protection of Fixed Microwave Systems
As proposed in the 6 GHz Second FNPRM, the Commission will protect
fixed microwave services from a significant risk of harmful
interference by requiring geofencing systems to determine location- and
frequency-based exclusion zones for GVP access points around fixed
microwave receivers based on the same criterion used by AFC systems to
protect microwave receivers from standard-power access points and fixed
client devices. Specifically, the geofencing systems will calculate
frequency-based exclusion zones using the same propagation models used
by the AFC systems to avoid causing an I/N greater than the -6 dB
interference protection criterion established for the AFC systems. The
-6 dB criterion was established as an appropriate threshold to protect
fixed microwave receivers. Individual GVP devices will use these
exclusion zones to determine where they are prohibited from
transmitting on particular frequencies to prevent harmful interference
from occurring.
Interference protection criterion. The 6 GHz Second FNPRM proposed
that geofencing systems calculate the GVP exclusion zones based on the
same -6 dB I/N interference protection criterion that the Commission
adopted in the 6 GHz First Order (85 FR 31390, May 26, 2020) for AFC
systems. EPRI characterizes -6 dB as the appropriate interference
protection metric, while AT&T states that this metric ``should be
adjusted in view of additive impacts and the `at sufferance' nature of
Part 15 RLAN devices.''
The Commission adopted the -6 dB I/N criterion for use by AFC
systems based on an extensive technical record and was supported by the
Fixed Wireless Communications Coalition, the Utilities Technology
Council et al., and other representatives of fixed microwave
incumbents. The -6 dB I/N metric has also been extensively used in
numerous computer simulations developed for analyzing the harmful
interference risk posed by unlicensed devices in the 6 GHz band. The -6
dB I/N interference protection criterion used by AFC systems has been
widely supported by 6 GHz unlicensed device proponents and microwave
incumbents. The -6 dB metric in conjunction with the propagation models
required in the Commission's rules have proven sufficient in enabling
adequate protection to fixed microwave receivers when standard power
devices access spectrum under the supervision of an AFC system. The
geofenced systems can similarly use this proven methodology to ensure
microwave receivers are protected when unlicensed GVP devices access
spectrum in a manner the geofenced system has determined will not
present a significant risk of harmful interference. Therefore, the
Commission is adopting this same metric for geofencing systems to use
when determining exclusion zones. Geofencing systems will be required
to determine exclusion zone boundaries based on calculating locations
where the I/N ratio exceeds -6 dB using the
[[Page 9150]]
propagation models specified in the Commission's rules.
While AT&T argues that additive interference undermines the
technical justification for using the -6 dB I/N metric, 6 GHz
unlicensed devices only present a risk of interference if they are in
the microwave antenna's main beam at a close enough distance. The
geofenced system that controls GVP access points' spectrum access will
prevent those devices from operating at locations where they would
present a significant risk of harmful interference. Furthermore, Monte
Carlo analysis by Apple shows that the additive effects of LPI and VLP
devices, operating without any frequency management mechanism such as a
geofencing or AFC system, do not present a significant risk of harmful
interference to microwave links. Therefore, the Commission does not
agree with AT&T that additive effect undermine the technical reasoning
for adopting the -6 dB metric. By adopting this metric, the Commission
ensures consistency between the calculation methods used by AFC and
geofencing systems which should enable geofencing administrators to
easily develop and implement these systems. Moreover, use of this
metric by AFC systems has been effective in preventing harmful
interference from occurring to licensed incumbents from standard power
device operations. In adopting the use of this metric by geofencing
systems, the Commission is not making a determination that any signal
received with an I/N greater than -6 dB would constitute ``harmful
interference'' but are instead using this as a conservative means to
ensure that microwave receivers are protected.
Propagation models. The 6 GHz Second FNPRM proposed that geofencing
systems, to determine the VLP device exclusion zones, use the same
propagation models that are used by AFC systems to provide channel and
power information to standard power access points and fixed client
devices. Specifically, the Commission proposed to require geofencing
systems to use the free space path-loss model at separation distances
of up to 30 meters, the Wireless World Initiative New Radio phase II
(WINNER II) model at separation distances greater than 30 meters and up
to and including 1 kilometer, and the Irregular Terrain Model (ITM)
combined with the appropriate clutter model at separation distances
greater than 1 kilometer. The Commission also proposed to require
geofencing systems to use site-specific information, including
buildings and terrain data, to determine the line-of-sight/non-line-of-
sight path component in the WINNER II model, where such data are
available. For evaluating paths where such data are not available, the
Commission proposed that geofencing systems use a probabilistic model
combining the line-of-sight path and non-line-of-sight path into a
single path-loss as set forth in the requirements for AFC systems. The
6 GHz Second FNPRM proposed that these propagation models be used to
calculate the GVP exclusion zones. These proposals were designed to
ensure consistency among operating locations and parameters for various
GVP systems, as well as consistency with the consensus methodology
WinnForum published for AFC systems.
EPRI agrees with the Commission that exclusion zones can be an
effective method to protect microwave receivers, ``provided that the
propagation models that define the zones align with findings from real-
world interference testing'' and that the models account for line-of-
sight paths between outdoor unlicensed devices and microwave receivers.
EPRI suggests using a purely geometric exclusion zone rather than
relying on the Commission's proposed propagation models. The geometric
exclusion zone would be based on a 30-meter radius around the microwave
receiver that extends into a keyhole shape with edges defined by the
microwave receive antenna 3 dB bandwidth out to a distance of 10
kilometers. EPRI states that such distance is necessary to eliminate a
discontinuity between the WINNER II and ITM propagation models used by
the AFC systems, which EPRI claims implies that AFC systems under-
protect FS systems. If the Commission uses a propagation model approach
to defining exclusion zones, EPRI advocates using free space path loss
as a reliable conservative approach. EPRI also questions whether the
ITM clutter models used by the AFCs are relevant for GVP devices
because they do not contain a specific category for roads and highways.
EPRI opines that automotive GVP devices are likely to be the first to
market and that clutter may not be accurately modeled because the
WINNER II model includes morphologies for ``urban'' and ``suburban''
areas but lacks guidance for roads and highways.
AT&T similarly advocates for a simple keyhole exclusion zone that
can be defined by a few discrete numbers such as latitude and longitude
of the microwave receiver, direction of the main beam, radius of a
circle around the receiver, and angle and distance defining a triangle
with its apex at the microwave receiver and its base perpendicular to
the main beam. It points out that if the exclusion zone is more
terrain-dependent, ``it could only be defined with a string of high-
precision latitude/longitude pairs,'' which is more complex and similar
to the AFC systems that already exist. AT&T suggests using free space
path loss to determine the geofencing area and including a 1.9-
kilometer buffer for mobility. According to AT&T, the ITM propagation
models ``are extremely nuanced and susceptible to major variations even
with minor changes in distance'' and that the algorithms can be
implemented in different ways leading to significantly different
results.
Apple, Broadcom et al. state that the AFC propagation models, which
are based on the distance between a GVP device and a microwave
receiver, ``sufficiently protects incumbents and can be easily applied
in the [GVP] context.'' Further, they claim that using these models
``ensures that the exclusion zones are effectively tailored to the
actual operating conditions.'' Apple, Broadcom et al. object to the
suggestion that only free space path loss be used for calculating
exclusion zones. They point out that the Commission previously found
the free space path loss model inappropriate ``because it fails to
account for obstruction and terrain variation.'' According to Apple,
Broadcom et al., while free space path loss can be appropriate for
short paths to account for a higher line-of-sight potential, ``it does
not reflect real-world operating conditions for other locations.''
The Commission is adopting rules that base the exclusion zones on
the same propagation models as used for AFC systems, which were adopted
after carefully considering the record. The Commission explained that
the adopted approach, which uses a combination of propagation models to
accommodate a variety of environments and distances, is the best way to
balance unlicensed device access and incumbent protection. Because GVP
devices will operate on the same spectrum as standard power devices,
their transmissions are subject to the same physical and temporal
environment as those devices. Thus, the Commission concludes that its
experience with these propagation models, which account for the 6 GHz
operating environment, since adopting the standard-power device rules
provides strong support for concluding that they are similarly
appropriate for managing GVP device spectrum access. Since the first
AFC systems were approved for commercial operation in February 2024,
the Commission has not received any reports that harmful interference
occurred to microwave
[[Page 9151]]
receivers from standard-power access points.
When the Commission adopted the standard-power device rules, the
record included contentions by microwave licensees that terrain and
clutter losses should not be assumed using statistical models and that
the appropriate propagation model should be free space path loss. The
Commission disagreed with the claims that a free space model must be
used in cases where clutter and terrain data are not known. While the
Commission adopted the free space path loss model for short separation
distances (up to 30 meters), it noted that this model drastically
underpredicts path loss for longer distances because there is almost
always interaction with the environment that reduces the signal level
below free space. As with standard power devices, using the free space
path loss model to protect microwave receivers from GVP devices would
overprotect such systems and unnecessarily restrict GVP devices
resulting in less efficient spectrum use.
By deciding to use the AFC propagation models, the Commission
rejects the notion that geofencing exclusion zones should be defined
using purely geometric models or simplified circle and triangle shapes,
as suggested by EPRI and A&T. Instead, the Commission will permit
geofencing systems flexibility to specify exclusion zones using more
complex boundaries, which the Commission recognizes can result in
exclusion zones with complex shapes. Therefore, to simplify and reduce
the data that needs to be conveyed to a GVP device, the Commission will
permit geofencing system administrators to simplify the exclusion zone
boundaries, so long as they do not provide any less protection to
microwave receivers. In other words, the exclusion zones can be
simplified or smoothed to ease implementation, as long as the result
protects microwave receivers to the same level or more than what the
propagation models and the -6 dB I/N metric indicate. To accommodate
GVP devices from different manufacturers and potentially multiple
geofencing systems, and to ensure that exclusion zones are calculated
and provided to GVP devices in a consistent manner, the Commission
expects that industry groups will create necessary standards, including
an interface specification.
The Commission disagrees with EPRI's concern that the ITM model
under-protects microwave systems due to a discontinuity between the
predicted propagation loss with the Winner II model at a distance of 1
kilometer. EPRI provides no actual evidence that the ITM model is
under-protecting the microwave receivers. In the 6 GHz First Order, the
Commission concluded that the ITM model was the appropriate propagation
model for the AFC systems to use for distances greater than 1
kilometer, noting that it is supported by the record and has served
reliably as a propagation model. In addition, the ITM model has been
used to determine spectrum availability in the spectrum access systems
(SAS) used to manage access to the 3550-3700 MHz band in the Citizens
Broadband Radio Service. Given the lack of actual evidence that the ITM
and Winner II models are not appropriate for use by the geofencing
systems and the Commission's previous experience with these models for
the AFC systems, the Commission sees no grounds to depart from the
propagation models proposed in the 6 GHz Second FNPRM.
Additionally, the Commission disagrees with EPRI's concern that the
clutter models used with the ITM model do not represent device use
along roads. The clutter models specify clutter levels based on broad
land use categories such as urban, suburban, and rural with the model
for rural areas using different modeling based on barren areas, high
crop yield fields, deciduous trees, coniferous trees, and village
center. Because roads are surrounded by buildings or trees that are
reflective of these categories, the Commission would expect the signals
from devices transmitting on or along roadways to experience
attenuation from clutter in the same manner as signals transmitted by
devices located away from the roadway. For example, a signal
transmitted from a GVP device located along a roadway in a suburban
area would experience clutter effects from the buildings and trees in
the surrounding environment that are reflective of a suburban
environment. EPRI appears to be expecting a degree of precision from
clutter models that is not realistic. The same considerations apply to
EPRI's concerns regarding the WINNER II model's lack of guidance for
use on roads.
GVP Transmit Height. The 6 GHz Second FNPRM stated that the
geofencing systems could use an antenna height above ground of 1.5
meters in the propagation models when creating the GVP exclusion zones.
AT&T points out that for unlicensed whitespace devices, the
``geofencing parameters explicitly consider the elevation--antenna
height--of the potentially interfering device.'' AT&T also contends
that an assumed antenna height of 1.5 meters is inappropriate because
the microwave receiver main beam is highly directional and therefore is
sensitive to changes in interferer elevation. AT&T suggests that the
``geofencing boundaries . . . should be determined using the worst-case
antenna elevation based on terrain, topology, or LIDAR data.''
The Commission expects that antenna height will not be a
significant factor in calculating exclusion zones because most GVP
device use will occur indoors. The computer simulations submitted by
Apple, Broadcom et al. that the Commission relied on when adopting the
rule to permit VLP operation assumed that only 6% of the people using
VLP devices would be outdoors. The Commission concluded that this
assumption was reasonable because it was based on Department of
Transportation and Environmental Protection Agency statistics. Because
transmissions from indoor GVP devices will be subject to significant
building attenuation, the Commission believes that operation of indoor
GVP devices at any elevation will not present a harmful interference
risk. Hence, for 94% of GVP device use, the device elevation will not
be a factor.
The Commission also expects the vast majority of outdoor GVP device
use will occur at ground level--that is, people will use the portable
devices outdoors at ground level. For such use, the Commission finds
that 1.5 meters above ground level is an appropriate approximate
height. The Commission also notes that the ITM model does account for
terrain and hence does compensate for any difference in terrain height
between the microwave receiver location and a GVP device being used at
an elevation of 1.5 meters above the ground level. While the WINNER II
model does not account for the actual terrain, because this model is
only used for distances less than one kilometer we do not expect that
there will be significant variations in terrain for most cases.
There will be a small number of situations where GVP devices are
used on building balconies and rooftops. In such cases, assuming a 1.5-
meter device height above ground level would not be appropriate.
However, the Commission cannot endorse AT&T's proposed worst-case
height solution based on terrain, topology, or LIDAR data as it would
result in significantly overprotecting microwave receivers in most
situations, such as when GVP devices are being used indoors, or at
lower heights. Considering the ever-increasing demand for spectrum, the
Commission cannot justify eliminating more spectrum than is necessary
from GVP use. Also, using such data, where available, would, in
[[Page 9152]]
effect, assume all in-building GVP use is on the building rooftops
instead of indoors or on lower elevation balconies, dramatically
reducing the GVP operating area absent an increased harmful
interference risk. The Commission also notes that LIDAR data is not
available in all locations.
To compensate for the relatively fewer GVP devices that may be
operating on building rooftops and balconies, the Commission is
requiring geofencing systems to assume a 10-meter height above ground
level for GVP devices when calculating exclusion zones. The Commission
is using a 10-meter height for the GVP access points because this is
the height assumed in OET Bulletin No. 69, which describes using the
terrain-dependent Longley-Rice point-to-point propagation model for
estimating received signal strength of television signals. OET Bulletin
No. 69 was used by the Commission to make broadcast television signal
coverage predictions when assigning channels during the transition from
analog to digital television. OET Bulletin No. 69 provides an
appropriate precedent for the assumed GVP device height for two
reasons. First, GVP devices, like television sets, will be used where
people live or work, which may be in buildings ranging in size from
one-story houses to multi-story buildings. When choosing the height to
use for OET Bulletin No. 69, the Commission chose a height that was
appropriate to represent the wide variety of possible antenna
locations. This height is also appropriate to represent the wide
variety of indoor GVP use. Second, the Longley-Rice propagation model
is the basis of the ITM model, which the Commission is requiring
geofencing systems to use for distances greater than one kilometer.
While using a 10-meter height will, in most cases, result in larger
than necessary exclusion zones, the Commission also notes that some
outdoor GVP use could occur at greater heights. In the latter case,
however, such use will only present a harmful interference risk if it
occurs on the same channel as being used by a microwave link and within
a microwave receiver's main beam within a few kilometers from the
microwave receiver location. The Commission concludes that such cases
are likely to be so rare as to present an insignificant risk of harmful
interference occurring. Moreover, similar to VLP devices, GVP devices
are designed to be inherently mobile, and any instances of potential
interference are expected to be fleeting.
Body Loss. The 6 GHz Second FNPRM, similar to the Commission's
conclusion for VLP devices in the 6 GHz Second Order, proposed to allow
geofencing systems to assume 4 dB for body loss when calculating
exclusion zones. AT&T urges the Commission not to assume that all GVP
devices will be body worn and subject to 4 dB of body loss, noting that
``there is no rule that requires VLP devices to be body worn'' and
therefore ``no basis for assuming [GVP] devices will, in fact, be body
worn.'' If the Commission adopts an assumption for body loss, AT&T
suggests that the rules bar certification for GVP devices that are not
explicitly designed to be body worn. AT&T also asserts that because
``VLP devices are likely to be deployed in pairs, . . . it is
irrational to assume that both endpoints of the [communication] will be
subject to body attenuation.'' UTC/EEI point out that not all VLP
devices will be oriented or used on the body where 4 dB of body loss
can be assumed to occur. EPRI states that if the GVP device is oriented
such that there is no body shielding to the microwave receiver, a 0 dB
body loss would be appropriate. EPRI also suggests that ``the first
mass-market VLP devices will be automotive'' and that, ``[b]ecause
automotive bodies have glass in all directions[,] . . . more study is
needed to determine what value of loss or gain is required to match
real-world deployments.''
Apple, Broadcom et al. disagree with AT&T's suggestion that the
Commission ignore body loss unless the rules require a device to be
body worn, noting that ``even if a device is not directly worn on the
body, proximity effects can still be present.'' Apple, Broadcom et al.
notes that the Commission previously concluded that `` `such losses
[still] occur due to absorption and reflections from a table or other
surface the device is sitting on or, for in-vehicle use, from the
vehicle's cabin.' '' Apple, Broadcom et al. also claim that ``[GVP
device] operations in cars will actually be more protective than on-
body operations'' because automotive bodies have close to 9 dB mean
attenuation--far higher than our assumed body loss value. API supports
using 4 dB body loss for GVP devices.
In the 6 GHz Second Order, the Commission explained that a body
loss value for analytic purposes must reflect not just the body loss
itself, but also the wide range of values possible, the varying
behavior of VLP device users, and the variety of uses for which VLP
devices may be employed. The Commission noted that a 4 dB body loss is
appropriate because ``body loss is used to represent attenuation from a
range of objects near the VLP device such as a human body or the
surface of table.'' The Commission also found that a 4 dB body loss
``appears to be a conservative assumption'' because ``the body loss
measurements submitted by Apple, Broadcom et al. and Meta show a
distribution with a mean higher than 4 dB and some measured
attenuations were much greater than the 8 dB maximum of the truncated
distributions used in the simulations.''
In the 6 GHz Third Order, the Commission recognized that several
related technical studies filed by Broadcom and Apple, Broadcom et al.,
referred to as the ENG Truck Receiver Studies, provided evidence to
support its conclusion that harmful interference would not occur to
electronic newsgathering (ENG) truck receivers from VLP device
operations. The ENG Truck Receiver Studies assumed 4 dB of body loss
for the transmissions from the VLP device. The Commission concluded in
the 6 GHz Third Order that using 4 dB for body loss in these link
budget calculations is consistent with assumptions that it found were
appropriate in the 6 GHz Second Order.
The Commission finds, consistent with its previous conclusions in
the 6 GHz Second Order and 6 GHz Third Order, that it is appropriate
for geofencing systems to assume a 4 dB body loss value when
calculating the exclusion zones to protect microwave receivers. Several
commenters object to an assumption of 4 dB of body loss because not all
GVP devices will be body worn. While the Commission agrees with
commenters that not all GVP devices will be body worn, the Commission
reiterates its statement from the 6 GHz Second Order that the term
``body loss'' refers not only to the attenuation when a GVP device is
used on or near a human body, but also to the attenuation from other
nearby objects, such as a table that the device is sitting on or a
vehicle's passenger cabin. Apple, Broadcom et al. concurs that ``body
loss'' can occur ``even if a device is not directly worn on the body''
because ``proximity effects can still be present.'' Although some
commenters appear to claim that the 4 dB body loss assumption should
not apply in certain scenarios, the Commission notes that they did not
submit any technical data to support those claims. Thus, based on the
record before the Commission, it will permit geofencing systems to
account for up to 4 dB body loss consistent with the Commission's
previous conclusion as to the appropriate body loss to assume for
interference related VLP device calculations.
The body-loss measurements that Apple, Broadcom et al. previously
submitted on the record illustrate that 4
[[Page 9153]]
dB is a conservative body-loss value. According to these measurements
of a smartphone transmitting in six different locations on six
different people, the measured body loss was greater than 4 dB 90% of
the time and could be as high as 30 dB. These measurements indicate
that excluding body loss from the exclusion zone calculation will
result in larger exclusion zones than are necessary to protect the
microwave links the vast majority of the time. Therefore, assuming no
body loss, as several commenters suggest, would conflict with the
Commission's goal to promote efficient spectrum use.
The Commission does not agree with EPRI that more study is needed
regarding VLP use in automobiles before the Commission adopts a body
loss value for the geofencing systems. As noted, body loss also refers
to loss from nearby objects. Notably, Apple, Broadcom, et al. cited a
technical study finding that, on average, vehicles cause 9 dB of signal
attenuation to devices operating in the 2 GHz band. While the 6 GHz
band was not explicitly tested, this study demonstrates that devices
operating in-vehicle at 6 GHz would experience some level of
attenuation. Therefore, because signals transmitted by a GVP device
within an automobile will be subject to some amount of attenuation from
the vehicle cabin, the Commission believes it is appropriate to assume
that at least 4 dB of attenuation will be present for this use case.
Aggregate interference. The 6 GHz Second FNPRM proposed that
geofencing systems not be required to consider aggregate interference
effects from multiple GVP devices, noting that these devices will
operate at a significantly lower power level than standard-power access
points and fixed client devices for which the Commission previously
determined that an aggregate interference limit is not necessary.
Apple, Broadcom et al. agree that the risk of aggregate interference
from GVP is even lower than for standard-power devices because ``GVP
devices will operate at a considerably lower power level compared to
standard power [access points]'' and the required contention-based
protocol will ``greatly decrease[ ] the likelihood of simultaneous
transmission that could lead to aggregate interference.'' EPRI claims
that its real-world testing confirms that additive interference effects
are real and that geofencing systems must acknowledge additive
interference. According to EPRI, locations where line-of-sight paths
occur between unlicensed devices and microwave receivers are not rare
corner cases and that when multiple devices operate at such locations
the aggregate interference effects significantly increase the potential
for harmful interference. AT&T suggests that the Commission follow the
practice adopted in the United Kingdom and the European Union ``where
an additional 4 dB margin was included to adjust for aggregate
effects.'' AT&T also cites an instance where the Commission assumed a 4
dB margin to account for aggregate interference when setting a power
flux density interference limit into satellite earth station receivers.
AT&T notes that the Commission's previous finding regarding aggregate
interference pre-dates the two technical studies filed by EPRI and
FirstEnergy and the technical study filed by Southern Company.
The two studies conducted by EPRI and FirstEnergy, which AT&T
references, purport to show measured reduction in microwave link fade
margin from aggregate effects of multiple access points. However, these
two studies show inconsistencies that cast doubt on the results. For
example, the first study shows that, in some instances, the reduction
in link fade margin actually decreases when multiple access points are
transmitting compared to when just one access point is transmitting but
increases in other instances. The Commission speculates that the
inconsistencies in the two EPRI and FirstEnergy studies are related to
the methodology employed for measuring the impact from unlicensed
device operation on microwave links. EPRI and FirstEnergy regularly
measured a baseline fade margin with no unlicensed devices transmitting
by reducing the microwave transmitter power level until bit errors
occurred. One or more unlicensed devices were then turned on and the
microwave link power level was reduced until errors occurred. The
difference in the microwave link power level at which errors occurred
between these two cases was the ``reduction in fade margin,'' which
EPRI and FirstEnergy claims is due to unlicensed device operation. But
this methodology is flawed because the fading level experienced on a
microwave link constantly changes, which means that the baseline fade
margin does not remain constant during the testing. To account for
variation in link fading, EPRI and FirstEnergy either used the baseline
fade margin before the unlicensed devices were turned on or
interpolated or calculated the average of the baseline fade margin
measurements made before and after the measurements with the unlicensed
devices. As the fade margin measurement plot in the second EPRI and
FirstEnergy test report shows, the baseline fade margin over the three-
day testing period varied between 25 and 29 dB and the difference
between two successive baseline fade margin measurements was as much as
2 dB. Based on the data in these test reports, it is difficult to
conclude whether the fade margin reduction was due to variation in the
baseline fade margin over time or was caused by the additive effect
from multiple unlicensed devices simultaneously transmitting. The
Commission also notes that when using multiple simultaneously
transmitting unlicensed devices, EPRI and FirstEnergy set them to use
``iperf-tenstreams'' which generates ``10 concurrent streams of maximum
rate TCP.'' This produced continuous extremely high-rate transmissions
instead of the bursty discontinuous transmissions typical of Wi-Fi.
Hence, the Commission would not expect this type of testing to
accurately model the effects of typical unlicensed devices. The
technical study by Southern Company, which AT&T also references, is
also lacking because it merely speculates that aggregate interference
could occur from multiple access points in a specific building rather
than actually measuring whether such aggregate interference actually
occurs. Therefore, the Commission does not find these technical studies
persuasive and concludes that there is no need to adjust the exclusion
zones based on the potential for aggregate interference from multiple
GVP devices.
AT&T points out that the Commission assumed a 4 dB factor for
aggregate interference when setting a power flux density (PFD) limit
for out-of-band emissions from base and mobile stations in the 3.7-3.98
GHz band into satellite earth station antennas in the adjacent 4-4.2
GHz band. The 3.7-3.98 GHz band has been auctioned to wireless mobile
broadband carriers. Spectrum use by wireless carriers typically differs
from spectrum use by unlicensed devices. Wireless carriers set up their
networks to provide ubiquitous coverage with higher power levels than
are permitted for unlicensed devices. Base stations employed by
wireless carriers transmit continuously, unlike the bursty
transmissions of unlicensed Wi-Fi devices. Given the differences in how
the licensed 3.7-3.98 GHz band is being used compared to the likely
characteristics of GVP devices, the Commission does not believe that
its prior decision assuming a 4 dB margin for aggregate interference in
the 3.7-3.98 GHz band is relevant to 6 GHz GVP devices.
[[Page 9154]]
AT&T refers to a statement from the United Kingdom spectrum
regulator on 5 and 6 GHz band Wi-Fi use and a report on a simulation
study conducted by the Electronic Communications Committee of the
European Conference on Postal and Telecommunications Administrations to
support a claim that the United Kingdom and the European Union use a 4
dB margin for aggregate effects. The Commission notes that neither of
these documents mention a 4 dB margin to compensate for the aggregate
interference effects.
Adjacent channel protection. The 6 GHz Second FNPRM proposed that
GVP exclusion zones only account for co-channel operations and not
consider adjacent channel operations. This is a departure from the
rules for standard-power devices, which require AFC systems to account
for the potential of standard-power devices causing harmful
interference to microwave links operating on an adjacent channel. The 6
GHz Second FNPRM explained that this was appropriate due to the
significantly lower operating power of GVP devices compared to
standard-power devices. AT&T argues that there is ``no basis to exclude
adjacent channel protection if the keyhole calculations indicate that
adjacent channel geofencing is warranted.'' Apple, Broadcom et al.
agree with the 6 GHz Second FNPRM proposal, noting that the Commission
already concluded in the 6 GHz First Order that the adjacent channel
interference risk to microwave receivers from standard-power devices is
low. They argue that because ``[GVP] devices will operate at
significantly lower power levels than standard-power devices, . . . the
already low risk [is] insignificant.''
The Commission will not require that geofencing systems account for
potential adjacent channel interference effects when determining
exclusion zones because the Commission does not believe that such
adjacent channel operations will present a significant harmful
interference risk to microwave receivers. The rules the Commission is
adopting for GVP devices require emissions to be suppressed by 20 dB at
1 megahertz outside the channel edge, by 28 dB at one channel bandwidth
from the channel center, and by 40 dB at one- and one-half times the
channel bandwidth away from channel center. This means that energy from
a GVP device will be limited to -9 dBm/MHz at one megahertz outside the
channel edge with even lower power at greater spectral distance. Given
the low energy level that GVP devices will emit into adjacent channels,
the Commission concludes that they are unlikely to present an
interference risk to microwave receivers on adjacent channels. Thus,
the Commission cannot justify imposing such additional complexity on
geofencing systems. The Commission recognizes that this is a departure
from its rules for standard-power devices. However, the Commission
concludes that the lower GVP signal levels compared to standard-power
devices (i.e., standard-power client devices operate at a maximum 17
dBm/MHz) justifies our approach.
Exclusion zone update interval. The 6 GHz Second FNPRM proposed to
require geofencing systems to obtain the most recent public access file
data from the Commission's ULS database at least once per day and to
recalculate the exclusion zones, as necessary, to account for any new
or updated information. The 6 GHz Second FNPRM explained that a once-
per-day interval is appropriate because ULS, which contains the data
required to determine exclusion zones to protect fixed microwave
receivers, is generally updated on a daily basis. Therefore, a daily
update interval would ensure that newly registered microwave receive
sites are promptly protected. Furthermore, the 6 GHz Second FNPRM
proposed to require GVP access points to obtain updated exclusion zones
from the geofencing systems at least once per day.
There were no comments opposing the daily ULS update interval for
geofencing systems. AT&T agrees that a daily ULS database update is
reasonable. The Commission will require geofencing systems to update
their data from the ULS database at least once per day and to update
the exclusion zones daily based on the updated data.
AT&T asks the Commission to require GVP access points to obtain
updated exclusion zones from the geofencing system every hour. AT&T
notes that this one-hour reauthentication interval would be consistent
with the rules for unlicensed whitespace devices and contends that the
Commission provided no rationale for not proposing the same rule for
GVP access points. However, this fails to acknowledge that GVP devices
will have different operational characteristics than white space
devices. White space devices are required to update hourly because
there are wireless microphones in the band that can be registered at
any time. In the 6 GHz band, newly registered microwave receivers are
added to the ULS database once a day. Consequently, it is unnecessary
for the geofencing systems to update the exclusion zones or for the GVP
access points to download the updated exclusion zones more than once a
day. Therefore, the Commission will require a GVP access point to
obtain updated exclusion zones from the geofencing system at least once
per day. If the GVP access point fails to obtain the updated
information on any given day, the GVP access point may continue to
operate until 11:59 p.m. of the following day at which time it must
cease operations until it can obtain updated frequency-specific
information for its location.
Microwave links may begin operation prior to obtaining a license so
long as certain criteria are met, such as completing successful
frequency coordination and filing an application that appears in the
ULS database as pending. In addition, temporary fixed microwave links
may be authorized by a blanket authorization, in which case the
licensee is not required to obtain approval from the Commission prior
to operating at specific locations or report the technical details of
their operation to the Commission. The 6 GHz Second FNPRM sought
comment on requiring geofencing systems to follow the same criteria for
protecting fixed and temporary fixed sites as AFC systems use for
standard power access points and fixed client devices. No comments from
the record directly address this issue. Accordingly, for the reasons
set forth in the 6 GHz First Report and Order, the Commission will
require that the geofencing systems protect pending facilities and
temporary fixed stations that are registered in ULS. Because the
geofencing systems must have knowledge of the location of temporary
fixed links in order to protect them from harmful interference, the
Commission will require operators of temporary fixed stations register
the details of their operations (transmitter and receiver location,
antenna height, antenna azimuth, antenna make, and model, etc.) in the
ULS database if they desire to be protected from potentially receiving
harmful interference from GVP devices in the U-NII-5 and U-NII-7 bands.
Exclusion or Inclusion Zones. Under the requirements the Commission
is adopting, geofencing systems will determine exclusion zones around
microwave receiver and radio astronomy observatories where GVP access
points are required to avoid operating on particular frequencies. The 6
GHz Second FNPRM proposed that as an alternative to defining exclusion
zones, the geofencing systems may also determine areas where particular
frequencies are available throughout the entire area based on the same
criteria used to calculate exclusion zones. Allowing geofencing systems
to specify
[[Page 9155]]
``inclusion zones'' instead of exclusion zones could provide increased
flexibility for implementing geofencing. No commenters addressed this
alternative. Because using either exclusion zones or inclusion zones
will provide equivalent protection to microwave receivers and radio
astronomy observatories, the Commission will permit geofencing systems
to use either an exclusion-zone or an inclusion-zone approach. The
Commission expects that industry groups will create necessary
standards, including addressing the most efficient method for
implementing incumbent protection.
Protection of FSS
The entire 6 GHz band is allocated for the FSS in the Earth-to-
space direction, except for the 7.075-7.125 GHz portion of the band.
Additionally, portions of the U-NII-7 and U-NII-8 bands are allocated
for FSS space-to-Earth (downlink) operations. However, there are no
licensed downlink earth stations in the U-NII-7 band. Sirius XM and
Globalstar, the only satellite licensees who filed comments in response
to the 6 GHz Second FNPRM, limited those comments to their U-NII-8 band
operations. Because the Commission is permitting GVP devices to operate
only in the U-NII-5 and U-NII-7 bands at this time, Sirius XM's and
Globalstar's concerns regarding their operations in the U-NII-8 band
are not relevant to GVP operation.
In the 6 GHz First Order, the Commission concluded that because the
satellites receiving in the U-NII-5 and U-NII-7 bands are limited to
geostationary orbits, approximately 35,800 kilometers above the
equator, the Commission found that standard power unlicensed devices
would be unlikely to cause harmful interference to the space station
receivers. The only restriction that the Commission adopted to protect
the satellite receivers, which it characterized as a ``precautionary
measure,'' was to require that outdoor standard-power access points
limit their maximum EIRP above a 30-degree elevation angle to 21 dBm.
In the 6 GHz Second Order, the Commission determined that no
restrictions on VLP devices are necessary to protect FSS Earth-to-space
operations. This conclusion was based on the fact that VLP devices,
operating at up to 14 dBm EIRP, transmit at significantly lower power
than the 21 dBm allowed for standard power access points above 30
degrees elevation.
The Commission concludes that GVP operations will not cause harmful
interference to FSS satellite receivers. FSS satellites in
geostationary orbits are unlikely to receive harmful interference from
GVP devices because of the relatively low transmit powers of the GVP
devices and the large distance to the satellites. This conclusion is
supported by a study conducted by RKF Engineering (2018 RKF Study),
which found that the interference level at the satellites would be less
than -20 dB I/N from 6 GHz unlicensed devices that included outdoor
access points operating at up 36 dBm. While Sirius XM criticized a
number of the assumptions used in the 2018 RKF Study, as the Commission
explained in the 6 GHz Third Order, Sirius XM's contentions do not
provide a reason to reconsider our conclusion about the likelihood of
interference occurring to FSS uplinks. The Commission also notes that
no one has produced any technical studies illustrating that GVP devices
operating at the power levels we are adopting will present a harmful
interference risk to geostationary satellite receivers.
The Commission does not believe it is necessary to adopt a
restriction on GVP EIRP for higher elevation angles as we did for
standard power access points. Because the Commission is prohibiting GVP
devices from use on fixed infrastructure, these will be portable,
battery-powered devices. Such devices will generally operate at the
lowest power necessary to maximize their operating time. While these
devices may operate at the maximum power the Commission is permitting
in certain situations, such as to overcome large body losses or to
compensate for longer than typical distances, we expect such situations
to be rare. This differs from access points, which typically operate at
a constant power level. Therefore, the Commission sees no reason to
adopt the precautionary restriction on power transmitted above 30
degrees elevation that the Commission applied to standard power access
points.
Protection of Passive Services
Radio astronomy. Several radio astronomy observatories located in
remote areas observe methanol spectral lines in the 6.65-6.6752 GHz
portion of the U-NII-7 band. The table of frequency allocations urges
that the Commission takes ``all practicable steps'' to protect the
radio astronomy service in the 6.650-6.675.2 GHz range from harmful
interference. In the 6 GHz Second FNPRM, the Commission proposed to
require that geofencing systems implement the same exclusion zone rules
for protecting radio astronomy sites in the 6.650-6.6752 GHz band as
standard power access points and fixed client devices, which are based
on the distance to the radio horizon. The locations of the protected
radio astronomy sites and the protection criteria for these sites are
specified in the standard power access point and fixed client device
rules.
The National Academy of Sciences' Committee on Radio Frequencies
(CORF) points to its previous arguments that VLP devices should avoid
channels that overlap the 6.7 GHz radio astronomy band. In the 6 GHz
Second Order, the Commission considered and rejected CORF's request to
prohibit VLP devices from using certain frequencies or channels to
protect radio astronomy operations, stating that VLP devices'
interference potential in the U-NII-7 band is even lower than for LPI
devices that were already permitted to operate at higher power levels
than those adopted for VLP devices. However, GVP devices will operate
at higher power than VLP, which increases their potential for causing
harmful interference to radio astronomy operations. Therefore, the
Commission will prohibit GVP access points from operating inside of
exclusion zones in the 6.65-6.6752 GHz portion of the U-NII-7 band used
by radio astronomy. The Commission concludes that the geofencing system
will prevent higher power GVP devices from operating co-frequency
inside exclusion zones around radio observatory sites where they could
cause harmful interference.
Earth-Exploration Satellite Service (EESS). Remote sensing using
the EESS, which CORF states is critical to weather prediction and
studying climate change and the Earth in general, operates in the
6.425-7.250 GHz band, which includes the U-NII-6, U-NII-7, and U-NII-8
bands. In the 6 GHz Second FNPRM, the Commission sought comment on the
harmful interference risk from GVP devices on oil platforms to EESS
monitoring operations. The Commission also sought comment on
appropriate restrictions for VLP device use on boats to protect EESS
operations, and if so, should those restrictions be limited to boats in
the oceans, given that EESS is used for sensing over the ocean. CORF
suggests that EESS (passive) observations in the U-NII-6, U-NII-7, and
U-NII-8 bands can be protected by programming GVP devices to avoid
these bands while in oceanic zones and coastal waters. The Commission
agrees with CORF and concludes that geofencing will prevent GVP devices
in the U-NII-7 band from operating co-frequency with EESS observations
within ocean exclusion zones. However, CORF has not indicated what
boundary should be used to designate ocean
[[Page 9156]]
exclusion zones. To balance EESS protection requirements with providing
flexibility to maximize locations in which GVP devices can operate, the
Commission will use the United States territorial sea border to define
the boundary of the ocean exclusion zones, which is 12 nautical miles
(nm) from the baseline of each coastal State. This will allow GVP
devices to operate near the coastlines while ensuring that EESS sensing
ocean temperatures avoid receiving harmful interference over ocean
areas.
The Commission will also exclude GVP access points from oil
platforms to mirror the rules for VLP devices, standard-power access
points, and low power indoor access points. The Commission notes that
Apple, Broadcom et al. and API support not permitting GVP access on oil
platforms. The Wi-Fi Alliance suggests removing all restrictions on
unlicensed operation on oil platforms, claiming the 2023 World Radio
Conference (WRC-23) resolved to migrate all EESS ocean sensor
measurements to other frequency bands. The Commission notes, however,
that the WRC-23 resolution cited by the Wi-Fi Alliance only resolved to
study other frequency bands for EESS and does not indicate that EESS
would stop using the 6 GHz band. Therefore, the Commission has no
grounds to change our policy regarding 6 GHz unlicensed devices on oil
platforms.
CORF also indicates that EESS sensing operations may be extended to
large inland bodies of water, such as the Great Lakes, and requests
that the Commission not allow VLP devices on boats in these bodies of
water. It suggests geofencing could also be used to prevent GVP
operations in these inland lakes The Commission finds these concerns
about potential future EESS use to be speculative and declines to
prohibit GVP devices from operating on boats in the Great Lakes or in
other large inland bodies of water at this time.
GVP Device Requirements
Geolocation capability. Consistent with the requirements for
standard power access points, in the 6 GHz Second FNPRM, the Commission
proposed to require that GVP access points include a geolocation
capability to determine their geographic coordinates. Additionally, the
Commission proposed that the geolocation capability include the ability
to determine location uncertainty in meters, with a 95% confidence
level, and that the applicant for certification of a GVP access point
demonstrate the accuracy of the geo-location method used and the
location uncertainty. The Commission further proposed to require a GVP
access point, using its geographic coordinates, to take this location
uncertainty into account when determining whether it is within an
exclusion zone. AT&T contends that geofencing proponents should
describe how devices will determine not only their location, but also
the accuracy associated with that location determination. Furthermore,
AT&T claims that the location accuracy determination must be specific
to the area in which the location measurement is being taken.
Alternatively, AT&T suggests that geofencing proponents explain how the
Commission's rules will ensure that any flexibility granted to
equipment manufacturers to develop individualized systems for
determining a device's location will meet those requirements.
The Commission sees no reason why geofencing proponents should have
to describe how GVP access points will determine their location and the
accuracy associated with that location determination, as suggested by
AT&T, because device manufacturers will be required to provide this
information as part of the equipment certification process. The
Commission's rules will require GVP device manufacturers to provide an
attestation describing the geolocation method used, the method's
accuracy, and the location uncertainty accuracy as part of the FCC
certification process. Therefore, the GVP manufacturers will be
required to demonstrate the accuracy of the geolocation method used and
the location uncertainty estimate. Device manufacturers of standard-
power access points have successfully demonstrated their devices'
compliance with the Commission's previous geolocation requirements.
Consistent with the Commission's previous actions for standard-
power access points and white space devices, the Commission will
require GVP access points to include a geolocation capability to
determine its geographic coordinates. Unlike for standard-power access
points, the Commission will not provide the option for the GVP access
points to use an external geolocation source. This is because the
Commission expects that most GVP access points will be devices, such as
mobile phones, that have a built-in geolocation capability. The
Commission also notes that no commenters have indicated that we should
provide the option for GVP access points to use an external geolocation
source. The Commission is requiring GVP access points to determine
their location uncertainty in meters with a 95% confidence level, as is
the case for standard-power access points. Furthermore, the Commission
is requiring that the GVP access point use its determined coordinates
and location uncertainty when comparing the device's specific location
to frequency-specific information (i.e., exclusion zones) obtained from
the geofencing system. This means that when the access point estimates
that the geolocation coordinates are less accurate, the GVP access
point will have to operate at a greater distance from the boundary of
the exclusion zone. Taking into account the uncertainty estimate when
determining whether the GVP access point is outside of an exclusion
zone recognizes the fact that no geolocation technique is absolutely
accurate and thereby provides a greater level of protection to the
microwave receivers. These geolocation requirements serve as part of
the multi-faceted methodology in protecting fixed microwave receivers
by ensuring GVP devices operate appropriately based on their location
respective to exclusion zones.
Geofence re-check interval. In the 6 GHz Second FNPRM, the
Commission proposed to require GVP access points to have the capability
to timely adjust their operating frequencies when moving into, out of,
or between exclusion zones. The Commission proposed flexible
requirements for the device re-check or update interval to enable
device designers to optimize efficiency while still ensuring that the
devices do not operate on channels where the -6dB I/N metric is not
met. The Commission proposed that the time interval for a geofenced
device to re-check its location and adjust its frequency usage must
decrease proportionally based on an increase in the mobile device's
speed. This would require a GVP access point to regularly re-check its
location and speed to properly identify its position with respect to
any exclusion zones that may exist within its vicinity. As an
additional safeguard, the Commission proposed to require a GVP access
point to determine its location and speed at least once every minute.
The Commission sought comment on the efficacy of its proposals and on
any alternatives that may better provide GVP device designers
sufficient flexibility without degrading the protection granted to
incumbents.
Apple, Broadcom et al. recommend the Commission permit
manufacturers to comply with a location re-check interval in a manner
that does not result in unnecessary, frequent checks that drain the
device's battery and impact the user experience. To that end, they
[[Page 9157]]
advocate that the Commission not require GVP access points to determine
their location and speed at least once per minute as this would
unnecessarily undermine device performance. Instead, they recommend the
Commission adopt a flexible and technology-neutral approach that does
not require a specific time interval or a particular technology
solution. Additionally, they urge the Commission to permit
manufacturers to demonstrate that their approach effectively complies
with the exclusion zone rules when submitting a new device for
certification.
AT&T suggests that the rules for unlicensed whitespace devices
could provide a model for how to protect fixed microwave incumbents and
points to white space provisions for a 60-second reauthorization
interval, a 1.9 km buffer, and a 100-meter reauthorization requirement.
Regarding an appropriate re-check interval, AT&T suggests that a GVP
access point be required to re-check its location every 60 seconds.
AT&T also suggests that a GVP access point be required to re-check its
location upon a location change (i.e., if the device moves a certain
distance), or due to a device's proximity to the nearest exclusion
zone.
The Commission will not require a specific methodology for the re-
check interval at which the GVP access point must re-check its location
and determine whether it is complying with the geofencing information.
Instead, the Commission will require that the GVP access point re-check
its location at an interval that ensures that the device adjusts its
operating frequencies within one second of when any portion of the
device's location uncertainty area crosses into an exclusion zone, so
as to ensure that no harmful interference occurs to incumbents. Rather
than being prescriptive, the Commission will permit device
manufacturers to choose any re-check interval methodology that ensures
that a GVP access point complies with this requirement. This
requirement will provide flexibility for device manufacturers and
promote innovative solutions without compromising incumbent protection.
The Commission disagrees with AT&T that it should follow an approach
based on the white space device requirements. The white space device
rules addressed mobility using rigid assumptions, such as a 60 second
recheck interval and a 1.9 km buffer, which was based on a mobile
device traveling at 70 mph and re-checking every 60 seconds. These
rigid assumptions deviate from the flexible approach the Commission is
taking with GVP devices. This flexible approach recognizes that some
geolocation solutions are able to provide additional information beyond
a device's current position, such as its velocity and acceleration. The
flexible approach will ensure that GVP devices re-check less frequently
if they are stationary or moving at slow speeds, thus conserving power.
Similarly, GVP devices traveling faster or near the boundary of an
exclusion zone will be required to re-check their location more
frequently. In this way, the flexible approach will provide superior
protection to licensees while enhancing GVP device operations. This
flexible approach is intended to facilitate the benefits of these
devices for the public while still protecting licensees. Given the
benefits of this flexible approach, the Commission sees no need to
follow the more rigid approach it used for mobile white space devices.
The Commission also notes that no mobile white space devices have ever
been certified and therefore the Commission has no real-world
experience with the efficacy of those more rigid restrictions in
protecting other users. Furthermore, AT&T does not present any specific
concerns that the proposed re-check interval, or any alternatives
presented on the record, will contribute to an increased harmful
interference risk.
Transmit Power Control. In the 6 GHz Second FNPRM, the Commission
proposed to require GVP devices operating within the U-NII-5 through U-
NII-8 bands to employ a transmit power control (TPC) mechanism that has
the capability to operate at least 6 dB below the maximum EIRP
permitted for the bands (e.g., 14 dBm or 21 dBm). The Commission
proactively determined that it did not expect that a TPC requirement
for GVP devices would present an undue burden on device manufacturers
because GVP devices were expected to be battery-powered devices and
were likely to implement TPC in order to conserve battery power. As a
result, the Commission reasoned that ``[b]ecause many VLP devices will
be capable of both geofenced and non-geofenced operation, these devices
will by necessity incorporate the ability to implement at least a 6 dB
power reduction.'' The Commission sought comment on a variety of issues
related to the relative power levels necessary for GVP devices to
mitigate any potential for harmful interference. More specifically, the
Commission asked whether there was a need to specify any additional TPC
requirements for GVP devices given that they would be permitted to
operate with higher power than VLP devices. The Commission noted that
there is a European requirement that TPC shall provide, on average, a
mitigation factor of at least 3 dB on the maximum permitted output
power of the systems; or, if transmit power control is not in use, then
the maximum permitted mean EIRP and the corresponding mean EIRP density
limit shall be reduced by 3 dB.
In response, API recommends that the Commission require TPC on all
VLP devices, not just those operating at higher powers. It suggests a
more expansive TPC power reduction with a 12 dB range, applied in steps
no greater than 3 dB, with the output power reduced to as low as 2 dBm
EIRP/-11 dBm/MHz EIRP PSD. It claims that this would help to minimize
interference to incumbents and other unlicensed 6 GHz users. Apple
Broadcom et al. notes that the Commission has already determined that
``a 6 dB [TPC] range is sufficient to protect incumbents,'' and that
API has provided ``no new evidence demonstrating that this conclusion
was incorrect.'' They claim that requiring a 12 dB TPC range would
negatively impact consumers and would dissuade manufacturers from
investing in both VLP and GVP devices because it would increase
transceiver complexity and cost.
The Commission will require GVP access points to meet the same TPC
requirements as stipulated in the Commission's rules for VLP devices.
GVP access points will be required to employ a TPC mechanism with the
capability to operate at least 6 dB below the maximum 11 dBm/MHz EIRP
PSD. The record lacks technical justification to adopt a different TPC
requirement than what is already in place for VLP devices. TPC would
help minimize the risk of interference to incumbents as it provides GVP
devices with the ability to adjust power levels and subsequently
operate at power levels that do not increase the risk of harmful
interference. The Commission believes that requiring GVP devices to
comply with the same rule in place for VLP devices is sufficient to
ensure that devices have the capability to dynamically adjust power to
operate both efficiently and in a manner that continues to minimize the
harmful interference risk to incumbents.
Contention-Based Protocol. To add to the protections afforded to
licensed incumbents, the 6 GHz Second FNPRM proposed to require that
GVP devices implement a contention-based protocol. While no comments
directly support requiring GVP devices to implement a contention-based
protocol and no comments oppose such a requirement, several commenters
highlight the efficacy of contention-based protocols in mitigating the
risk of harmful
[[Page 9158]]
interference. GVP devices will be operating co-channel with both LPI
and VLP unlicensed devices. Requiring use of a contention-based
protocol will help promote efficient spectrum sharing between the
different types of unlicensed devices. Furthermore, GVP devices will
likely also be capable of operating as VLP devices, which are required
to employ a contention-based protocol. Consistent with the Commission's
rules for VLP unlicensed devices, the Commission will require GVP
devices to implement a contention-based protocol that will act to avoid
channels on which incumbent systems are transmitting and to promote
efficient spectrum usage in channels where other unlicensed users are
transmitting.
Fixed Infrastructure. In the 6 GHz Second FNPRM, the Commission
proposed to prohibit GVP devices from operating as part of a fixed
outdoor infrastructure as an additional measure to reduce the
likelihood of harmful interference to licensed incumbent users. The
Commission notes that no commenters oppose the adoption of this
prohibition. API, the only commenter to address this issue, agrees that
GVP devices attached to fixed outdoor infrastructure should be
prohibited. Consistent with the requirements adopted for VLP devices in
the 6 GHz Second Order, the Commission will prohibit GVP devices from
operating as part of a fixed outdoor infrastructure. Thus, GVP devices
will be prohibited from attaching to outdoor infrastructure, such as
poles or buildings, which will help ensure that the GVP devices are
used only for mobile applications. Device mobility prevents GVP devices
from remaining in potentially problematic locations for significant
periods of time. In addition, as the 6GHz Second Order explained with
regard to VLP devices, by prohibiting GVP use as part of fixed outdoor
infrastructure, the Commission is ensuring that the GVP devices will be
subject to body and/or clutter loss and that most of the GVP devices
will operate at 1.5 meters above ground.
Integrated Antenna. In the 6 GHz Second FNPRM, the Commission
proposed to require that GVP access points employ a permanently
attached integrated antenna. An identical provision requiring use of an
integrated antenna currently applies to LPI access points and
subordinate devices. No commenters addressed the proposed integrated
antenna requirement. As proposed, the Commission will require GVP
access points to use a permanently attached integrated antenna. Because
this requirement will prevent users from replacing GVP antennas with
high gain directional antennas, it will help ensure that GVP use
complies with the power limits that are specified in terms of radiated
power (i.e., EIRP).
In the 6 GHz Second Order, the Commission defined a VLP device as
``a device that operates in the 5.925-6.425 GHz and 6.525-6.875 GHz
bands and has an integrated antenna.'' However, the Commission
inadvertently did not add VLP devices to the rule provision requiring a
permanently attached integrated antenna for low power indoor and
subordinate devices. For consistency, the Commission now adds VLP
devices to this rule provision. The Commission finds that notice and
comment are unnecessary as simply extending the application of this
requirement from LPI and subordinate devices to VLP devices for the
sake of consistency with the existing rule definition is insignificant
in nature and the impact would be inconsequential to the industry and
to the public.
GVP Client-to-Client Communications
In the 6 GHz Second FNPRM, the Commission proposed to permit direct
client-to-client communications between GVP client devices when they
are both under the control of the same GVP access point and the
geofencing system determines that they are operating outside of any
geofencing restrictions; i.e., there are channels available for GVP use
that are not subject to geofencing requirements in the location where
these devices are being used. Apple, Broadcom et al. ``support the
concept of direct client communications between client devices when
operating under geofencing requirements.'' The Ultra Wide Band Alliance
(UWBA) also supports client-to-client communications, emphasizing that
clients can use reduced transmit power to reach another client directly
and that overall traffic will be reduced by reducing clients
communicating through an access point. UTC/EEI raise concerns that
``client-to-client operations will exponentially increase the
interference threat to licensed microwave systems, and the Commission
should refrain from authorizing [client-to-client] for low power indoor
(``LPI'') and VLP operations.'' They suggest that the record does not
provide sufficient evidence that geofencing will be able to control VLP
client-to-client communications.
The Commission adopts its proposal to allow direct communication
between two client devices under control of a GVP access point subject
to the client devices being required to operate on the frequency in
either the U-NII-5 or U-NII-7 band that they are using to communicate
with the GVP access point. All GVP access points will still be subject
to the applicable geofencing requirements, including location and
geofencing recheck intervals and switching channels or ceasing
communications should they enter an exclusion zone and are currently
using a channel that is prohibited within that area. If a GVP access
point switches frequencies, the client devices will also be required to
switch frequencies to continue operating in a client-to-client mode.
The Commission notes that UTC/EEI's concerns do not address direct
communication between client devices under the control of GVP access
points but instead are directed at LPI and VLP operations. The GVP
access point and the client devices under its control will operate only
on a frequency consistent with the exclusion zones obtained from the
geofencing system. Because each client device will be limited to 6 dB
less power than what is permitted for the controlling GVP access point,
they will operate close enough to the access point to keep them from
operating within any exclusion zone, thus ensuring they do not operate
in locations and on channels that could potentially increase the risk
of harmful interference to microwave receivers. Because each client
device in this scenario would be limited to using the maximum power
permitted for GVP client devices for the intra-client communications,
there would be no increase in the potential for causing harmful
interference to microwave receivers compared to the client devices each
individually communicating with the controlling GVP access point. As
Wi-Fi Alliance and UWBA point out, direct client-to-client
communication will allow reduced overall traffic through an access
point thus promoting a more efficient use of spectrum.
In the 6 GHz Second FNPRM, the Commission also proposed to permit
GVP devices that are operating under the control of the same low power
indoor access point to directly communicate with each other. In
addition, the Commission sought comment on permitting direct
communication between clients of low power indoor access points. The
Commission is deferring any decision on client-to-client communications
for devices operating under the control of low power indoor access
points.
The Commission notes that the rules it is adopting permit GVP
access points to directly communicate with each other. This
communication can be conducted at the power levels permitted for GVP
access points--i.e., at a maximum 11 dBm/MHz EIRP PSD and
[[Page 9159]]
24 dBm EIRP in accordance with the exclusion zones provided by a
geofencing system. Therefore, devices that would typically operate as
client devices, such as body-worn augmented reality glasses, smart
wristwatches, or laptop computers, can operate at the higher access
point power level if they meet the requirements of GVP access points,
such as having a geolocation capability and operating on frequencies
and at power levels only in accordance with the exclusion zones
provided by a geofencing system. These devices will not be able to
operate at the higher GVP access point power level unless they have
first obtained exclusion zone information. This may require them to
initially operate at lower power levels as a GVP client device or VLP
device to communicate with an access point to obtain the exclusion
zones before they can operate at the higher GVP access point power
level. The Commission notes that nothing in its rules prohibits a GVP
access point from relaying exclusion zone information obtained from a
geofencing system to another GVP access point. Consequently, a GVP
access point could operate as a client device to another GVP access
point, use this connection to register with and obtain exclusion zone
information from a geofencing system, and then switch to operation as a
GVP access point and increase its transmit power level accordingly.
Approval of Geofencing Systems
The Commission delegates to the Office of Engineering and
Technology (OET) the authority to administer the geofencing systems and
geofencing system operator functions in accordance with the rules the
Commission is adopting to govern 6 GHz band geofencing systems. The
Commission also delegates OET authority to develop specific methods
that will be used to designate geofencing system operators; to
designate geofencing system operators; to develop procedures that these
geofencing system operators will use to ensure compliance with the
requirements for geofencing system operations; to make determinations
regarding the continued acceptability of individual geofencing system
operators; and to perform other functions as needed to administer the
geofencing systems. The Commission amends part 0 of its rules to
delegate to OET authority to oversee the geofencing systems.
OET's review process to designate geofencing system operators
should ensure adequate testing to verify that the geofencing systems
are calculating appropriate exclusion zones in conformance with the
Commission's geofencing system rules. When the Commission adopted rules
for AFC systems, it directed OET to follow a multi-step testing and
review process to approve AFC operators and to ensure that AFC system
operators administered their systems with minimal chance of harmful
interference occurring to licensed incumbents. In doing so, the
Commission and OET gained substantial experience in determining the
specific steps necessary to ensure efficient administration of
unlicensed device access to spectrum using automated coordination
mechanisms. Given this history of review, certification, and testing,
the Commission is confident that OET has sufficient expertise
overseeing spectrum access management system development. As such, the
Commission does not believe it is necessary to require or specifically
spell out overly prescriptive review, testing, and administration
procedures here. Instead, the Commission delegates authority to OET to
develop a review and testing process for geofencing systems.
During AFC system development, industry groups took an active role
in developing the AFC systems and the AFC test process. Specifically,
the WInnForum developed a functional requirements document that
specified many operational requirements for the AFC systems, and the
Wi-Fi Alliance developed an interface standard for the communications
between the standard-power access points and AFC systems. The Wi-Fi
Alliance developed a plan for AFC system lab testing, and the WInnForum
and the Wi-Fi Alliance jointly developed test vectors for lab testing.
The test plan and test vectors were used as one step in the AFC system
test process before approval for commercial operations. The development
of the geofencing systems may be distinct from that of the AFC systems,
and the Commission anticipates the development and approval of a
diverse set of solutions. The Commission encourages industry groups,
including, but not limited to WInnForum and the Wi-Fi Alliance, to
develop geofencing system specifications as well as test processes and
test vectors that can be used to verify the proper geofencing system
functioning. The Commission notes that the WInnForum has indicated its
willingness to support geofencing system development and a desire ``to
work with the Commission as well as all stakeholders in the development
of specifications, recommendations and reports that will be required to
develop and ultimately certify VLP geofencing systems.'' FWCC indicates
that its members ``stand ready to work with other stakeholders through
the WInnForum to develop and test appropriate geofencing systems.'' The
Commission welcomes industry group efforts, such as those from the
WInnForum and Wi-Fi Alliance, to develop geofencing systems to enable
GVP device deployment and encourages microwave incumbents to
participate in such efforts.
The Commission will permit OET to designate multiple geofencing
systems as implied in the 6 GHz Second FNPRM. While the 6 GHz Second
FNPRM did not explicitly address whether there should be multiple or a
single geofencing system operator, the Commission clearly contemplated
the potential designation of multiple geofencing system operators by
proposing several rules that presumed there would be multiple
geofencing system operators. For example, the Commission proposed that
``[f]or centralized geofencing systems, geofencing system operators
must provide continuous service.'' It also proposed requirements ``for
geofencing system operators'' and for ``[e]ach geofencing system and
operator thereof.'' In seeking comment on these proposed rules, the
Commission implicitly expressed that it intended to consider permitting
multiple geofencing system operators rather than only a single
operator. No commenters addressed whether the Commission should
designate multiple geofencing operators. Designating multiple
geofencing system operators is consistent with the Commission's actions
for 6 GHz AFC systems, television white spaces, and CBRS. Designating
multiple geofencing systems will prevent one party from obtaining a
monopoly, which should provide an incentive for geofencing system
operators to provide reliable service and to keep costs low.
In the 6 GHz Second FNPRM, the Commission proposed that geofencing
systems may charge fees for providing service and that the Commission
may, upon request, review the fees and require changes to the fees if
it finds them to be unreasonable. No commenters addressed this fee
issue. The Commission appreciates that different financial models are
likely to be employed by geofencing systems. For example, a device
manufacturer may operate a geofencing system to provide service to GVP
access points it manufactures without charging any fees to the access
point user. Other geofencing systems may employ a subscription model
requiring the device
[[Page 9160]]
user to pay for services. The Commission will not prohibit geofencing
systems from charging fees for their services. As has been the case for
AFC systems, the Commission expects that there will be multiple
geofencing systems approved for commercial operations and that
competition from these different systems will keep any fees charged to
reasonable levels. However, as a safeguard, the Commission adopts its
proposal that it may, upon request, review the fees charged and require
changes if they are unreasonable.
In the 6 GHz Second FNPRM, the Commission proposed that centralized
geofencing systems must provide continuous service to all GVP devices
for which they are designated to provide service, and that if a
geofencing system ceases operation, the operator must provide at least
30-days' notice to the Commission and make arrangements for those
devices to continue to receive exclusion zone update information. No
commenters addressed this proposal. This requirement addresses a
concern that if a geofencing system stops operating, GVP devices may be
stranded with no means to obtain updated geofencing exclusion zones. To
ensure that consumers who use GVP devices are protected from such an
occurrence, the Commission is adopting this requirement. However, upon
review, the Commission believes the term ``designated'' is potentially
unclear as it implies that some entity has designated that the
geofencing system is to provide service to particular GVP devices.
Instead, the Commission shall replace ``are designated'' with ``have
agreed'' in the rule to avoid any confusion.
Technical Rules
Emission mask. In the 6 GHz Second FNPRM, the Commission proposed
to require GVP devices within the U-NII-5 through U-NII-8 bands to
comply with the transmission emission mask adopted for standard-power
and LPI devices in the 6 GHz First Order and for VLP devices in the 6
GHz Second Order. The Commission reasoned that because GVP devices
would likely operate in the same bands and on the same channels as VLP,
LPI, and standard-power 6 GHz devices and need to protect the same
incumbent operations, utilizing the same emission mask for GVP devices
is appropriate. The Commission stated that using the same mask would
ensure that licensed incumbents are fully protected from unlicensed
adjacent channel operations. The Commission believed that specifying
the same emissions requirements would reduce costs by permitting
devices throughout the VLP ecosystem to use the same filters and
benefit from economies of scale. No commenters addressed the proposed
transmission GVP emission mask. For the reasons discussed in 6 GHz
Second FNPRM, the Commission adopts the proposed transmission emission
mask.
This emission mask requires GVP devices to suppress their power
spectral density by 20 dB at one megahertz outside of an unlicensed
device's channel edge, 28 dB at one channel bandwidth from an
unlicensed device's channel center, and 40 dB at one and one-half times
the channel bandwidth away from an unlicensed device's channel center.
At frequencies between one megahertz outside an unlicensed device's
channel edge and one channel bandwidth from the center of the channel,
the limits are linearly interpolated between the 20 dB and 28 dB
suppression levels. At frequencies between one and one and one-half
times an unlicensed device's channel bandwidth from the center of the
channel, the limits are linearly interpolated between the 28 dB and 40
dB. Emissions removed from the channel center by more than one and one-
half times the channel bandwidth, but within the U-NII-5 and U-NII-8
bands, are to be suppressed by at least 40 dB.
Emission Limits outside of U-NII-5 and U-NII-8. As proposed in the
6 GHz Second FNPRM, the Commission is adopting emission limits for GVP
devices outside of the 6 GHz band that are identical to the emission
limits adopted in the 6 GHz First Order for standard-power and low
power indoor devices and in the 6 GHz Second Order for VLP devices.
Specifically, the Commission is adopting a -27 dBm/MHz EIRP limit at
frequencies below the bottom of the U-NII-5 band (5.925 GHz) and above
the upper edge of the U-NII-8 band (7.125 GHz), but will not apply this
limit between the sub-bands, i.e., between the U-NII-5 and U-NII-6, the
U-NII-6 and U-NII-7, and the U-NII-7 and U-NII-8 bands. Those emissions
are already subject to an emission mask discussed in this document. The
Commission notes that these limits are designed to protect cellular
vehicle-to-everything (C-V2X) operations below and federal operations
above the 6 GHz band. While the Commission previously determined that
the -27 dBm/MHz limit was sufficient to ensure C-V2X operations were
protected from harmful interference from U-NII devices operating in
other bands, in the 6 GHz Second FNPRM, the Commission sought comment
on whether any adjustments are needed to the Commission's VLP device
rules to adequately protect C-V2X operation in vehicles. The Commission
is deferring consideration of adjusting the in-vehicle VLP device OOBE
issue raised in the 6 GHz Second FNPRM at this time, as potential
adjustments to those limits are outside of the scope of this instant
document, which is directed to authorizing GVP devices, and are more
appropriately considered in a future proceeding.
Prior to adoption of the 6 GHz Second FNPRM, NTIA filed comments
directed at VLP operations that included a Department of Transportation
study (DoT Exhibit) addressing C-V2X protection requirements in the
5.895-5.925 GHz Intelligent Transportation Systems (ITS) band in which
C-V2X technology is used. ITS operators in this band transmit basic
safety messages for crash-avoidance and require low-latency, harmful-
interference-free operation. According to the DoT Exhibit, testing
showed that if 6 GHz devices that comply with the -27 dBm/MHz OOBE
limit were to operate inside of a motor vehicle, the operational range
of C-V2X receivers operating in the same vehicle would decrease by more
than 50%. The DoT Exhibit claims that implementing both parts of a two-
part compromise submitted by several VLP proponents, which would
require VLP devices to prioritize operations to frequencies above 6.105
GHz and limit VLP OOBE below 5.925 GHz to -37 dBm/MHz, is necessary to
protect C-V2X receivers.
The Commission notes that no commenter opposed adopting a GVP out-
of-band emission (OOBE) limit below the U-NII-5 band and above the U-
NII-8 band. The Wi-Fi Alliance contends that given the adequate
protection afforded to C-V2X operations by the OOBE limit in place for
other U-NII devices, there is no reason to subject GVP devices to more
restrictive OOBE limits than for VLP devices. Qualcomm Incorporated
(Qualcomm) claims that the Commission should adopt a more stringent
OOBE level for VLP devices and that this level of protection should be
extended to GVP devices. It contends that at the transmit power level
of 21 dBm for GVP devices, Qualcomm's 6 GHz chipsets support an OOBE
level of -38 dBm/MHz at the 5.925 GHz edge, which is already well below
-37 dBm/MHz and would not require any transmit power reduction for
unlicensed operations in the 320, 160, 80, 40, or 20 megahertz-wide Wi-
Fi channels closest to the 5.925 GHz band edge. Thus, Qualcomm claims
that ``there is no technical obstacle to 6 GHz VLP unlicensed devices
complying with a -37 dBm/MHz OOBE level that is
[[Page 9161]]
needed to protect C-V2X operation in the 5.9 GHz band from harmful
interference.'' It requests that the Commission maintain the 6.105 GHz
prioritization rule, which can be relaxed to 6.0 GHz, and at the same
time adopt a more stringent OOBE limit at the bottom edge of the U-NII-
5 band.
The 5G Automotive Association (5GAA) asserts that the Commission's
-27 dBm/MHz VLP, and by extension the proposed GVP, OOBE limit is
insufficient. According to 5GAA, DOT testing shows that when one or
more VLP devices are in close proximity (i.e., inside a vehicle), their
respective OOBE reduces the range at which C-V2X devices can
effectively communicate by more than 50%, particularly in non-line-of-
sight scenarios. It claims that the U-NII interference from adjacent
channels could reduce the ideal 300-meter range for safety applications
to as little as 25 meters, thus diminishing driver response time and
impacting critical safety alerts. Therefore, 5GAA proposes an OOBE no
less restrictive than -37 dBm/MHz. 5GAA also challenges the
Commission's conclusion that more stringent protection is not required
as C-V2X devices are already designed to coexist with one another. It
explains that this misconstrues the system in place that coordinates
with other C-V2X devices, which is not true for VLP devices because
they operate outside the C-V2X system. Additionally, it claims that VLP
devices can operate with higher duty cycles over a several-second
period in which critical C-V2X messages need to be successfully
transmitted. The Alliance for Automotive Innovation claims that in
addition to prioritizing VLP operation frequencies above 6105 MHz, the
Commission should adopt the -37 dBm/MHz OOBE limit for VLP devices. It
contends that this limit has been agreed to by stakeholders in the
unlicensed and C-V2X industries. It also claims that ongoing DOT
testing is being done to assess the interference risks presented by
mobile VLP devices in the lower U-NII-5 band. 5GAA has filed several
slides that it claims are from a presentation given by DOT about U-NII-
5 band test results.
The Association of State Highway and Transportation Officials
(ASHTO) et al. echoes the overall sentiment of the automotive industry
and opines that while a prioritization rule helps to mitigate the
potential for harmful interference, the Commission has acknowledged
that many VLP devices will still operate on the lowermost channels.
While ASHTO et al. make no specific request regarding GVP devices, they
do however request that the Commission adopt a -37 dBm/MHz OOBE limit
for VLP devices, which will provide C-V2X safety operations much-needed
protection. They claim that this OOBE limit can be achieved without
lowering in-band VLP transmit power and that VLP devices comply with an
European Union -45 dBm/MHz OOBE limit without impacting their transmit
power.
The Commission declines to adopt a general GVP OOBE limit lower
than what it originally proposed in the 6 GHz Second FNPRM--e.g., -37
dBm/MHz. In particular, the Commission cannot rely on the testing
scenario in the DOT Exhibit filed by NTIA and DOT on October 10, 2023,
as a basis for a real-world interference analysis. The DOT Exhibit
analysis included operations from devices in the U-NII-4 band and is
intended to extrapolate its findings to the U-NII-5 band. In its
analysis, DOT selected operational parameters from channel 171 (5855
MHz) and applied them in a manner intended to represent a channel whose
OOBE it claimed could potentially interfere with CV2X channel 183 (5915
MHz). However, this analysis is not persuasive because U-NII-4 devices
have different operational parameters than U-NII-5 GVP devices.
Operational parameters for U-NII-4 devices include a maximum of 36 dBm
EIRP for 40 MHz channels and when spanning the bands of U-NII-3 and U-
NII-4 or utilizing concatenated channels to create an 80 MHz channel
this power limit is not raised. In addition, devices operating in the
U-NII-4 band are only permitted to operate indoors and must not be
housed in a weatherized enclosure. Therefore, a device configured in
the manner in which it was configured in the DOT Exhibit could not
exist under the Commission's current rules. Likewise, there are
operational differences for GVP devices that do not apply to U-NII-4
Channel 171. For instance, the power limit the Commission is adopting
for U-NII-5 GVP devices is lower than those permitted for U-NII-4
devices. In fact, the maximum EIRP limit that the Commission adopts
today for GVP devices is 12 dB lower than those permitted for a U-NII-4
access point. In addition, devices authorized to operate under U-NII-5
rules must suppress emission by as much as 40 dB outside of its
intended operating channel, as opposed to a U-NII-4 device where no
such in-band channel emission mask is required by the Commission's
rules. The Commission notes that the use cases and the resultant rules
of the UNII-4 and UNII-5 bands were derived for different purposes.
Each rule set is uniquely defined and not intended for substitution or
cross-application.
The DOT Exhibit also used a 70% duty cycle for the unlicensed
devices. However, with the current proposed uses of unlicensed devices
in the 6 GHz band, GVP devices will utilize wide channels up to 320
MHz, as opposed to the 80 MHz channel the DOT Exhibit intended to
model. Assuming that the 80 MHz wide channel selection was appropriate,
the Commission notes that wider channels (i.e. channels exceeding 20
MHz) and channels with more advanced modulations schemes tend to
transfer larger amounts of data faster. Thus, the resultant duty cycle
is typically lower than for narrower channels or for legacy technology
with less advanced modulation schemes. Because the commenters
advocating for a lower OOBE limit rely on the DOT Exhibit as evidence
for their arguments, their arguments are not persuasive. The Commission
cannot express an opinion about the more recent DOT testing that 5GAA
references because the two slides they provide summarizing the testing
do not provide adequate technical details for us to reach any
conclusion. The Commission also notes that the Wi-Fi channel plan
starts at 5.945 GHz, which provides a 20 megahertz-wide guard band to
the edge of the U-NII-5 band, thereby providing additional protection
to C-V2X operations. In addition, the requirement to prioritize
operations above 6.105 GHz, noted in this document, will minimize the
number of devices operating near the lower portion of the 6 GHz band
closest to C-V2X operations. Thus, based on the record, the Commission
remains unconvinced that a more stringent OOBE limit for GVP U-NII-5
devices is necessary to protect ITS services in the adjacent band. As
such, the Commission is extending the -27 dBm/MHz OOBE limit currently
applied for VLP, standard-power, and low power indoor devices to GVP
devices.
Prioritization of operations over 6.105 GHz. To provide protection
from harmful interference to C-V2X operations below 5.925 GHz, in the 6
GHz Second FNPRM, the Commission proposed to impose a channel
prioritization requirement on GVP devices. The Commission reasoned that
because GVP devices could be mobile and potentially used near C-V2X
receivers, it proposed to require GVP devices to prioritize spectrum
above 6.105 GHz. This prioritization requirement was part of a
compromise proposal between the auto industry, chip manufacturers, and
technology aggregators, whereby it was claimed that prioritizing
channels above 6.105 GHz
[[Page 9162]]
will reduce the likelihood of VLP devices operating adjacent to the ITS
band when VLP devices are used in vehicles. The Commission adopted this
prioritization suggestion for VLP devices in the 6 GHz Second Order to
protect ITS operations below the U-NII-5 band from harmful
interference.
Several commenters generally support adopting this prioritization
requirement for GVP devices, while no commenters opposed imposing this
requirement. Qualcomm initially supported the prioritization of
operations over 6.105 GHz but in a more recent filing has proposed
lowering this threshold. Qualcomm now contends that lowering the
prioritization threshold from 6.105 GHz to 6.0 GHz is feasible, would
continue to protect CV2X reception, and would provide additional
channels to be used when a GVP device first select an operating channel
in accordance with the prioritization rule.
The Commission finds that its original analysis supporting such
prioritization for VLP devices applies equally to GVP devices for the
same underlying reasons. Prioritizing channels for operations above
6.105 GHz provides an additional layer of protection for both in-
vehicle and out-of-vehicle devices by helping to reduce congestion in
the lower portion of the band. This approach also enhances protection
for adjacent band devices by statistically increasing the average
spectral separation from the CV2X channels, thereby reducing the
likelihood of harmful interference. At the same time, it avoids the
unnecessary exclusion of valuable 6 GHz spectrum from potential use.
The combination of existing out-of-band emission (OOBE) limits, channel
mask requirements, and the prioritization of operations above 6.105 GHz
constitutes a comprehensive framework of technical restrictions.
Collectively, these measures are expected to provide sufficient
protection and mitigate the potential for harmful interference into
CV2X receivers operating in adjacent bands. As previously noted, these
restrictions were adopted for VLP devices out of an abundance of
caution to ensure that safety of life services below the U-NII-5 band
are protected from harmful interference. Therefore, the Commission is
requiring GVP devices to prioritize operations on frequencies above
6.105 GHz prior to operating on frequencies between 5.925 GHz and 6.105
GHz.
The Commission sets 6.105 GHz as the breakpoint for prioritization
rather than use 6.0 GHz, as Qualcomm suggests. No commenters other than
Qualcomm suggest using 6.0 GHz for this purpose and Qualcomm has
provided no technical data supporting its position. Given the lack of
justification for adopting a different prioritization scheme for GVP
devices than for VLP devices, the Commission sees no reason to adopt a
different rule for GVP devices.
GVP Device Registration. In the 6 GHz First Order, the Commission
defined specific information that standard-power access points are
required to provide when registering with an AFC system. These
parameters include geographic coordinates (latitude and longitude
referenced to North American Datum 1983 (NAD 83)), antenna height above
ground level, FCC identifier (FCC ID), and unique manufacturer's serial
number. The AFC system requires an access point's latitude and
longitude coordinates and antenna height above ground to determine
which frequencies are available at the access point's location. The AFC
system also uses the FCC ID and the access point's serial number to
verify that the device is authorized for 6 GHz band operations and, if
necessary, to address any interference concerns. Consistent with the
requirements set forth for standard-power devices operating under the
control of an AFC system, the Commission will impose similar
requirements for GVP devices to register with a geofencing system when
requesting exclusion zones. To register, a GVP access point will be
required to provide the geofencing system with the access point's FCC
ID and either its unique manufacturer's serial number or its model
name/number or other information sufficient to uniquely identify the
device manufacturer and model. Although the access point's FCC ID,
serial number, model name/number, or other information uniquely
identifying the device manufacturer and model are not required to
calculate exclusion zones, geofencing systems will use the information
for two purposes. First, the information will be used to authenticate
the access point to ensure that no unauthorized devices are operating
in the band. Geofencing systems will verify the device's FCC ID by
accessing the Commission's Equipment Authorization System (EAS)
database. Second, the information will be used for interference
mitigation and enforcement purposes to investigate the source if
harmful interference were to occur. During the registration process,
GVP access points are required to provide sufficient information
necessary for geofencing systems to assign exclusion zones for initial
operation.
Consistent with the requirements for AFC systems, the Commission
will require geofencing systems to store registered information in a
secure database until a GVP access point ceases operation, which the
Commission will define as a VLP access point not contacting the
geofencing system to verify exclusion zone information for more than
three months. In addition, since GVP access points will be in motion,
they may need to download additional exclusion zone information, and
they are required to contact the geofencing system daily to obtain any
updated exclusion zones. As a result, new information will get updated
in the geofencing systems' databases on at least a daily basis, which
alleviates the need to store registered information for longer than
three months. To ensure users' privacy, the geofencing system will use
the registered data only to protect incumbents and for potential
interference mitigation.
In previous filings, several parties voiced privacy concerns
related to device registration in the AFC system, stating that
registration requirements would compromise user privacy. The Commission
will require that GVP access points provide geofencing systems with
only the information necessary to receive its geofenced area of
operation. A GVP access point will obtain exclusion zones for the area
in which it is located from the geofencing system that will enable it
to determine the frequencies on which it may operate and the power
level it may transmit at. The exclusion zones may be downloaded for
areas with varying levels of geographic granularity, including but not
limited to: polygons with specified vertices, a circle of specified
radius centered at a point, or a broader region up to and including
entire states. Consequently, the GVP access point will not need to
provide its specific latitude and longitude to download the exclusion
zones and will not need to continuously provide its coordinates to the
geofencing system as it moves. The Commission believes this approach
will provide greater flexibility in implementing the geofencing system
without raising any potential privacy concerns.
Security Issues. In the 6 GHz Second FNPRM, the Commission proposed
to require that GVP access points and geofencing systems incorporate
adequate security measures. While the Commission received no comments
in response to these security proposals, previous security requirements
adopted for AFC standard power access points received strong support.
Reliable and secure communication between any GVP devices and
associated geofencing systems are essential for successful GVP
operations and incumbents' protection. Consistent with the Commission's
[[Page 9163]]
previous actions and the proposal in the 6 GHz Second FNPRM, the
Commission will require that GVP access points and geofencing systems
employ protocols and procedures to ensure that all communications and
interactions between the access points and the geofencing system are
accurate and secure and that unauthorized parties cannot access or
alter the exclusion zones sent to an access point. These security
measures must (1) prevent GVP access points from accessing geofencing
systems not approved by the Commission, (2) ensure that unauthorized
parties cannot modify devices to operate in a manner inconsistent with
the rules and licensed incumbent protection criteria, and (3) ensure
that communications between VLP access points and geofencing systems
are secure to prevent corruption or unauthorized interception of data.
Additionally, geofencing systems must incorporate security measures to
protect against unauthorized data input or alteration of stored data
(e.g., database information and the list of excluded/available
frequencies) and to protect the communication link between the
geofencing system and Commission databases. The Commission will also
require that geofencing systems and/or associated GVP access points
establish communications authentication procedures for communications
between GVP access points and GVP client devices. The Commission does
not mandate specific security models. Instead, the Commission will
require GVP device manufacturers and geofencing system operators to
demonstrate that their systems contain the necessary communication and
information security features during the device certification and
geofencing system approval processes.
International Borders. In the 6 GHz Second FNPRM, the Commission
proposed that GVP operations would have to comply with international
agreements with Canada and Mexico. No commenters addressed this
proposal. As is the case for AFC systems, the Commission will require
the geofencing systems to implement the terms of international
agreements with Canada and Mexico by protecting microwave operations in
Canada and Mexico near the United States border.
Restrictions on GVP device use on airplanes. In the 6 GHz Second
FNPRM the Commission sought comment on permitting GVP devices to be
more generally used onboard commercial and general aviation aircraft.
Additionally, the Commission sought comment on whether it should permit
GVP devices to operate across all flight phases, whether GVP devices
could be permitted to operate only when above 10,000 feet, and whether
to permit GVP devices to operate on aircraft at all. Apple, Broadcom et
al. note that while the Commission banned standard-power access points
from operating on any moving vehicle including aircraft, ``the
Commission's geofencing proposal . . . is explicitly designed to be
simple enough to facilitate mobile operations without imposing
unnecessary device or . . . system complexity.'' Furthermore, they
claim that ``[p]ortability is the key feature for the [GVP] device
class.''
The Commission will prohibit GVP device use on board any aircraft.
While the Commission recognizes that unlicensed GVP proponents want to
expand the opportunity for unlicensed connectivity on aircraft, the
Commission notes that it already authorized VLP devices to operate on
aircraft above 10,000 feet in the U-NII-5 band. The Commission finds
there are logistical issues that would prevent GVP devices from
adequately operating while in compliance with the geofencing
requirements. For example, GVP devices in aircraft would likely be
unable to check their location and verify they are not operating in an
exclusion zone. While most fixed links are directed to the horizon and
below and would not be impacted by GVP operations in aircraft at high
altitudes, the Commission recognizes there are some links that are
configured to point above the horizon to establish links to sites at
higher elevation. In these scenarios, a GVP device operating on an
aircraft that is unable to update its location could transmit while in
the main beam of a microwave link. Therefore, the Commission will
prohibit the use of GVP devices on aircraft.
In the 6 GHz Second FNPRM, the Commission noted that VLP devices
mounted on an unmanned aircraft system (UAS) could pose more than an
insignificant harmful interference risk, given the potential for a UAS
to fly almost anywhere and have a clear line-of-sight to a microwave
receiver. The Commission also recognized that an exclusion zone for UAS
usage would be much larger than for general usage because a UAS flies
at a higher altitude than the 1.5 meters that the Commission proposed
that geofencing systems would assume in calculating exclusion zones.
Nonetheless, the Commission sought comment on whether there are
operational limitations or guidelines that it could adopt to permit VLP
devices to operate mounted on a UAS. API, the only commenter to address
GVP UAS use, recommends prohibiting GVP use on UAS regardless of their
operating altitude. The Commission will not permit GVP use on UAS.
Because UAS may fly at altitudes exceeding the 10-meter height that the
Commission is mandating geofencing systems assume in calculating
exclusion zones, the Commission believes such use will present a
harmful interference risk.
Mandatory firmware updates. AT&T contends that the Commission
should mandate that ``all new unlicensed devices be required to accept
mandatory firmware updates that alter operating parameters.'' AT&T
points to a statement by the R St. Institute that `` `once spectrum is
designated for unlicensed use, it cannot be reallocated as the most
productive use of particular bands changes.' '' AT&T claims that its
proposal is consistent with NTIA Commerce Spectrum Management Advisory
Committee's (CSMAC) views, which recommended that `` `[a]ccess to new
unlicensed bands should generally be conditioned in ways that reserve
the flexibility to reallocate a band in the future or to change its
operating rules.' '' APCO International states that the Commission
should, wherever possible, require unlicensed devices and systems to
have capability to modify system parameters through over-the-air
firmware updates.
In reply, Apple, Broadcom et al. maintain that mandatory firmware
updates are ``unnecessary, would impose substantial costs on
manufacturers, and could undermine the cybersecurity of consumer
devices.'' They contend that ``a change to a device's firmware could
require a manufacturer to seek recertification,'' which ``is a lengthy
process and therefore should not be approached lightly.'' They state
that ``rather than maximizing spectrum efficiency, . . . a mandate that
every unlicensed device must permit over-the-air . . . firmware updates
that can change the device's core radio functions would create a
serious security risk.'' Apple, Broadcom et al. claim that such a
change would ``require[ ] manufacturers to build in a pathway that a
threat actor could exploit to remotely increase unlicensed devices'
power levels or frequency ranges across the country.''
In the 6 GHz Third Order, the Commission declined to impose a
mandatory firmware update for VLP devices because of its conclusion
that there is an insignificant risk that harmful interference would
occur due to VLP device operations. The Commission noted that the vast
majority of devices have the inherent capability for firmware updates
as manufacturers regularly make changes and upgrades to correct bugs,
enable more efficient
[[Page 9164]]
operation, or add capabilities. The Commission believes that this same
rationale applies to GVP devices. As the Commission noted in the 6 GHz
Third Order, such a mandate could be complex and was not raised in the
6 GHz Second FNPRM, and therefore, the Commission does not have a
record to explore such a mandate. Given the Commission's conclusion
that there is an insignificant risk that harmful interference will
occur due to the operation of GVP devices in the U-NII-5 and U-NII-7
bands, the Commission does not believe that such a mandate is
necessary. A firmware mandate is even less necessary for GVP devices
than for VLP devices because GVP devices will be under the supervision
of geofencing systems. The geofencing systems will be able to adjust
the operating frequencies and exclusion zone calculations if required
by future rule changes or to respond in the event of a harmful
interference incident. Additionally, manufacturers typically design
devices to support firmware updates, even in the absence of a mandate.
These updates are commonly used to correct software issues, improve
performance, or modify device behavior. Given these factors, the
Commission does not see a compelling reason to impose a firmware or
software update mandate. No evidence has been presented to justify such
a requirement and imposing one would amount to an unnecessary
regulatory burden. Therefore, the Commission declines to mandate
automatic over-the-air firmware updates for GVP devices.
Enforcement instructions. The National Public Safety
Telecommunications Council (NPSTC) states that ``it is imperative that
6 GHz licensees have a viable mechanism to report and expeditiously
resolve any . . . harmful interference to critical microwave links.''
It notes that several AFC systems have committed to establish a ``
`centralized means to receive and address complaints regarding
purported harmful interference from AFC-authorized unlicensed
operations.' '' NTPSC contends that even if these recommended
procedures are used, they would only apply to AFC-controlled 6 GHz
devices and are concerned that this is not a comprehensive approach. If
harmful interference does occur, NPSTC is unclear how the interference
source will be determined, i.e., whether it is from a standard-power,
low power indoor, VLP, or a GVP device. It claims that licensed
stakeholders in the 6 GHz band need a viable means to report and
expeditiously resolve harmful interference regardless of the 6 GHz
unlicensed device involved.
NPSTC indicates that past enforcement cases show that the
Commission's established procedures for resolving interference issues
are not as expeditious as it would prefer. As an example, it refers to
an ongoing interference case involving an unlicensed device interfering
with a commercial wireless system that took almost a year to address.
NPSTC recommends that ``the Commission put in place a more expeditious
and effective process to resolve any harmful interference.''
In reply, Apple, Broadcom et al. view the Commission's current
enforcement and reporting mechanisms as proven to be sufficient as
evidenced by the operation of millions of unlicensed consumer devices
in the 6 GHz band, beginning in 2020, without any evidence of harmful
interference to licensed users. They state that ``unlicensed devices
have also operated in other bands with sensitive users, such as the 5
GHz band, without the need for special enforcement rules.'' They
believe that the Commission has enforcement requirements in place and
that ``any additional enforcement requirements would be superfluous to
the Commission's current enforcement authority.''
The Commission finds that in a general sense, and as it applies to
6 GHz devices, the Commission has a long history of performing
interference analyses and using such analyses in carefully crafting
part 15 rules to protect incumbent systems. These analyses have
demonstrated that the likelihood of a 6 GHz unlicensed device causing
harmful interference is insignificant, based on the technical rules
that the Commission has adopted. As 6 GHz devices are unlicensed, the
Commission notes that Sec. 15.5(b) of the Commission's rules provides
that ``[o]peration of an intentional, unintentional, or incidental
radiator is subject to the condition[ ] that no harmful interference is
caused.'' In the unlikely event that harmful interference does occur
due to 6 GHz device operations, Sec. 15.5(c) of the Commission's rules
provides that ``[t]he operator of a radio frequency device shall be
required to cease operating the device upon notification by a
Commission representative that the device is causing harmful
interference,'' even if the device was properly certified and
configured, and that ``[o]peration shall not resume until the condition
causing the harmful interference has been corrected.'' The Commission
recognizes the Enforcement Bureau's efforts and reiterates that the
Commission does not promise a zero chance of interference. As Apple,
Broadcom et al. point out, unlicensed devices have operated in many
bands without the requirement to include additional enforcement
protections. As it pertains to low power indoor and VLP devices, the
Commission believes that the rules that it has adopted are sufficient
to adequately protect incumbent users from harmful interference.
Because these enforcement and compliance mechanisms are applicable
to GVP devices, the Commission is adopting provisions to enable harmful
interference that occurs from the operation of GVP devices to be
mitigated. In the 6 GHz Second FNPRM, the Commission recognized a need
for geofenced systems to seamlessly coordinate enforcement requests and
database updates. In that respect, it proposed several enforcement-
related rules concerning data updates and enforcement instructions. The
Commission is adopting these proposals. That is, the following rules
that are consistent with the rules for AFC systems will apply to
geofencing systems. The Commission requires geofencing systems to
ensure that their databases contain the information required by the
Commission's rules, including frequency-specific exclusion zones and
GVP access point's authorization parameters. The Commission also
requires the geofenced systems to respond in a timely manner to verify,
correct, or remove, as appropriate, data in the event that the
Commission or a party presents a claim of inaccuracies in the
geofencing system. In addition, the Commission requires geofencing
systems to establish and follow protocols to comply with enforcement
instructions from the Commission, including discontinuing GVP access
point operations on specified frequencies in designated geographic
areas and predetermined exclusion zones. The Commission also requires
geofencing systems to comply with its instructions to adjust exclusion
zones, if necessary, to more accurately reflect the harmful
interference potential.
As for NPSTC's request that the Commission put in place a more
expeditious and effective process to resolve any harmful interference,
this appears to be directed at the Commission's enforcement procedures
in general rather than specifically at 6 GHz unlicensed GVP operations.
The example case that NPSTC refers to as ``interference from an
unlicensed device to a licensed commercial wireless system'' does not
involve someone
[[Page 9165]]
operating an unlicensed part 15 device in accordance with the
Commission's rules that causes interference to a licensed receiver.
Instead, it involves someone operating a device in violation of the
Commission's rules which causes harmful interference to a licensed
radio receiver. While the operator of the interfering radio equipment
in that case did not have a license to transmit in the frequency band
at issue and in that sense was ``unlicensed,'' that operator was not
operating an unlicensed part 15 device in compliance with the
Commission's rules such as would be the case for GVP devices. To the
extent that NPSTC's concerns are that the Commission's enforcement
rules and procedures are not sufficiently expeditious, this involves
addressing issues more far reaching than the scope of the FCC's
proceeding.
Definitions of GVP Access Points and Client Devices. In the 6 GHz
Second FNPRM, the Commission proposed to define a GVP access point as
an access point that operates in the 5.925-7.125 GHz band, has an
integrated antenna, and uses a geofencing system to determine channel
availability at its location. The 6 GHz Second FNPRM explained that
this definition adequately describes the types of VLP devices that
could operate under a geofencing system, and the proposed requirement
for an integrated antenna, which is consistent with the current rules
for indoor access points and subordinate devices, will help ensure that
GVP devices cannot be easily modified to increase their EIRP. No
commenters addressed this proposed definition. This definition is a
straightforward description of a GVP access point. Other than adjusting
the frequency range to account for the fact that the Commission is not
permitting GVP devices to operate in the U-NII-6 or U-NII-8 bands, the
Commission sees no reason to modify this definition, which the
Commission shall incorporate into its rules.
The 6 GHz Second FNPRM did not propose a definition of GVP client
devices, and no commenters have suggested such a definition. However,
the 6 GHz Second FNPRM noted that client devices that operate under the
control of a GVP access point may also be capable of operating under
the control of LPI access points and standard power access points, in
which case the client devices must adjust their power levels depending
on which type of access point they are connected to. The Commission's
rules currently define a client device as ``[a] U-NII device whose
transmissions are generally under the control of an access point and is
not capable of initiating a network.'' This definition currently
applies to client devices that operate under the control of either
standard-power or LPI access points. This definition, by its current
wording, will also apply to client devices that operate under the
control of a GVP access point. Therefore, the Commission sees no need
to adopt an additional definition that explicitly defines a GVP client
device. All client devices will be restricted to transmitting at power
levels no more than 6 dB less than the level at which the controlling
access point is authorized to operate, whether that access point is a
standard-power, low power indoor, or GVP access point.
Benefits and Costs
In the 6 GHz Second FNPRM, the Commission sought comment on the
benefits and costs of its proposals for implementing GVP devices in the
6 GHz band. The Commission did not receive any comments that included
economic benefit or cost estimates for GVP devices.
Benefit estimates from rules the Commission previously adopted in
the FCC's proceeding have been substantial. One report estimates that
opening the 6 GHz band to unlicensed use has produced $870 billion in
economic value in 2023 and 2024 together, and that this total benefit
will increase to $1.2 trillion by 2027. In the 6GHz Second Order, the
Commission conservatively estimated benefits from permitting VLP
devices to operate in the U-NII-5 and U-NII-7 bands to be $2 billion.
In the 6 GHz Third Order, the Commission conservatively estimated
benefits from opening the U-NII-6 and U-NII-8 bands to VLP devices
would be $820 million.
Consistent with previous experience in the FCC's proceeding, the
Commission anticipates that the rules permitting GVP devices to operate
in the U-NII-5 and U-NII-7 portions of the 6 GHz band will yield
substantial benefits. The higher power GVP devices will enable
increased data rates and greater range for current VLP applications.
While geofencing will limit GVP operating areas, even a 5% improvement
in economic value derived from these devices relative to the
Commission's estimated benefits for VLP in the U-NII-5 and U-NII-7
portions of the 6 GHz band would result in $100 million in additional
benefits over a five-year period, or on average, annual benefits of $20
million. The Commission believes this estimate to be conservative
because higher data rates and range will not only enhance existing VLP
applications, but also create opportunities for new applications,
including augmented reality/virtual reality, short-range hotspots,
automation processes, and indoor location and navigation. The expanded
opportunities presented by these new GVP applications have the
potential to yield benefits comparable to the benefits from existing
VLP devices already operating within areas that may be subject to
geofencing. Thus, GVP use may yield benefits much higher than $100
million over a longer time horizon.
The Commission anticipates that the rules its promulgating will
impose no additional costs on the public. While manufacturers and users
may incur costs in setting up the new GVP ecosystem, these costs will
be voluntarily incurred and thus will not result in a private cost
without a countervailing private benefit. This would include any costs
for switching to new devices or developing and maintaining the
geofencing systems. 6 GHz band users will be protected from harmful
interference by the geofencing system, so there will be no costs
imposed on other 6 GHz band users. The Commission therefore concludes
that permitting GVP devices to operate in the 6 GHz band will yield
substantial economic benefits to the American public.
Ordering Clauses
It is ordered that, pursuant to sections 2, 4(i), 302, and 303 of
the Communications Act of 1934, as amended, 47 U.S.C. 152, 154(i),
302a, 303, the Order is hereby adopted.
It is further ordered that the Fourth Report and Order shall be
effective 60 days after publication in the Federal Register.
It is further ordered that the Commission's Office of the Secretary
shall send a copy of the Fourth Report and Order, including the Final
Regulatory Flexibility Analysis, to the Chief Counsel for Advocacy of
the Small Business Administration.
It is further ordered that the Commission shall send a copy of the
Fourth Report and Order in a report to be sent to Congress and the
Government Accountability Office pursuant to the Congressional Review
Act, see 5 U.S.C. 801(a)(1)(A).
List of Subjects
47 CFR Part 0
Authority delegations (Government agencies), Communications,
Telecommunications.
47 CFR Part 15
Communications equipment, Radio.
[[Page 9166]]
Federal Communications Commission.
Marlene Dortch,
Secretary.
Final Rules
For the reasons discussed in the preamble, the Federal
Communications Commission amends 47 CFR parts 0 and 15 as follows:
PART 0--COMMISSION ORGANIZATION
0
1. The authority citation for part 0 continues to read as follows:
Authority: 47 U.S.C. 151, 154(i), 154(j), 155, 225, 409, and
1754, unless otherwise noted.
0
2. Amend Sec. 0.241 by revising paragraph (k) to read as follows:
Sec. 0.241 Authority delegated.
* * * * *
(k) The Chief of the Office of Engineering and Technology is
delegated authority to administer the Automated Frequency Coordination
(AFC) systems, AFC system operator functions, geofencing systems, and
geofencing system operator functions set forth in subpart E of part 15
of this chapter. The Chief is delegated authority to develop specific
methods that will be used to designate AFC system and geofencing system
operators; to designate AFC system and geofencing system operators; to
develop procedures that these AFC system and geofencing system
operators will use to ensure compliance with the requirements for AFC
system and geofencing system operations; to make determinations
regarding the continued acceptability of individual AFC system and
geofencing system operators; and to perform other functions as needed
to administer the AFC and geofencing systems.
* * * * *
PART 15--RADIO FREQUENCY DEVICES
0
3. The authority citation for part 15 continues to read as follows:
Authority: 47 U.S.C. 154, 302a, 303, 304, 307, 336, 544a, and
549.
0
4. Amend Sec. 15.403 by adding the definitions of ``Geofenced variable
power access point,'' ``Geofencing,'' and ``Geofencing system'' in
alphabetical order, to read as follows:
Sec. 15.403 Definitions.
* * * * *
Geofenced variable power access point. For the purpose of this
subpart, an access point that operates in the 5.925-6.425 GHz and
6.525-6.875 GHz bands, has an integrated antenna, and uses a geofencing
system to determine channel availability at its location.
Geofencing. For the purposes of this subpart, a method of
establishing exclusion zones within which geofenced variable power
access points and associated devices are not permitted to operate on
frequencies specified by the geofencing system; and inclusions zones
within which such devices are permitted to operate on frequencies
specified by the geofencing system.
Geofencing system. A system that automatically determines frequency
specific zones where geofenced variable power access points are either
permitted to operate or not permitted to operate in the 5.925-6.425 GHz
and 6.525-6.875 GHz bands.
* * * * *
0
5. Amend Sec. 15.407 by:
0
a. Redesignating paragraphs (a)(7) and (8) as paragraphs (a)(8)(i) and
(ii);
0
b. Adding a new paragraph (a)(7);
0
c. Revising newly redesignated paragraph (a)(8) and paragraphs (a)(10),
(d)(1)(i) and (iv), and (d)(3) and (5);
0
d. Removing and reserving paragraph (d)(7);
0
e. Revising paragraphs (d)(8) through (10), (k)(3), and (k)(7)(iii);
0
f. Redesignating paragraphs (l), (m), and (n) as paragraphs (n), (o),
and (p);
0
g. Adding new paragraphs (l) and (m); and
0
h. Revising newly redesignated paragraphs (n), (o), and (p).
The revisions and additions read as follows:
Sec. 15.407 General technical requirements.
(a) * * *
(7) For a geofenced variable power access point operating in the
5.925-6.425 GHz or 6.525-6.875 GHz band, the maximum power spectral
density must not exceed 11 dBm e.i.r.p. in any 1-megahertz band. In
addition, the maximum e.i.r.p. over the frequency band of operation
must not exceed 24 dBm.
(8)(i) For client devices, except for fixed client devices as
defined in this subpart, operating under the control of a standard
power access point in 5.925-6.425 GHz and 6.525-6.875 GHz bands, the
maximum power spectral density must not exceed 17 dBm e.i.r.p. in any
1-megahertz band, the maximum e.i.r.p. over the frequency band of
operation must not exceed 30 dBm, and the device must limit its power
to no more than 6 dB below its associated standard power access point's
authorized transmit power.
(ii) For client devices operating under the control of an indoor
access point in the 5.925-7.125 GHz bands, the maximum power spectral
density must not exceed -1 dBm e.i.r.p. in any 1-megahertz band, and
the maximum e.i.r.p. over the frequency band of operation must not
exceed 24 dBm.
(iii) For client devices operating under the control of a geofenced
variable power access point in the 5.925-6.425 GHz and 6.525-6.875 GHz
bands, the maximum power spectral density must not exceed 5 dBm
e.i.r.p. in any 1-megahertz band, the maximum e.i.r.p. over the
frequency band of operation must not exceed 18 dBm, and the device must
limit its power to no more than 6 dB below its associated geofenced
variable power access point's authorized transmit power.
* * * * *
(10) Access points operating under the provisions of paragraphs
(a)(5), (6), (7) and (9) of this section must employ a permanently
attached integrated antenna.
* * * * *
(d) * * *
(1) * * *
(i) Oil platforms. Standard power access points, fixed client
devices, geofenced variable power access points, very low power
devices, and low-power indoor access points in the 5.925-7.125 GHz band
are prohibited from operating on oil platforms.
* * * * *
(iv) Aircraft. Standard power access points, fixed client devices,
geofenced variable power access points, very low power devices, and
low-power indoor access points in the 5.925-7.125 GHz band are
prohibited from operating on aircraft, except that very low power
devices and low-power indoor access points are permitted to operate in
the 5.925-6.425 GHz bands in large aircraft while flying above 10,000
feet.
* * * * *
(3) Transmitters operating under the provisions of paragraphs
(a)(5) and (6) and (a)(8)(ii) of this section are limited to indoor
locations.
* * * * *
(5)(i) In the 5.925-7.125 GHz band, client devices must operate
under the control of a standard power access point, indoor access
point, subordinate device, or geofenced variable power access point;
Subordinate devices must operate under the control of an indoor access
point.
(ii) Access points and subordinate devices may connect to other
access points or subordinate devices.
(iii) Fixed client devices may only connect to a standard power
access point.
[[Page 9167]]
(iv) In all cases, an exception exists such that a client device
may transmit brief messages to an access point when attempting to join
its network after detecting a signal that confirms that an access point
is operating on a particular channel.
(v) Client devices are prohibited from connecting directly to
another client device, except that client devices under the control of
the same geofenced variable power access point may communicate directly
with each other using the same frequency they are using to communicate
with the geofenced variable power access point.
* * * * *
(8) Very low power devices, geofenced variable power access points,
and clients operating under the control of a geofenced variable power
access point may not be installed on fixed outdoor infrastructure. Such
devices may not be mounted on outdoor structures, such as buildings or
poles.
(9) Geofenced variable power access points and very low power
devices must prioritize operations on frequencies above 6.105 GHz prior
to operating on frequencies between 5.925 GHz and 6.105 GHz.
(10) Geofenced variable power access points and very low power
devices operating in the 5.925-7.125 GHz band shall employ a transmit
power control (TPC) mechanism with the capability to operate at least 6
dB below the device's maximum e.i.r.p. PSD value.
* * * * *
(k) * * *
(3) An AFC system must obtain information on protected services
within the 5.925-6.425 GHz and 6.525-6.875 GHz bands from Commission
databases and use that information to determine frequency availability
for standard power access points and fixed client devices. Based on the
criteria specified in paragraph (n) of this section, an AFC system must
establish location and frequency-based exclusion zones (both co-channel
and adjacent channel) around fixed microwave receivers operating in the
5.925-6.425 GHz and 6.525-6.875 GHz bands. Individual standard power
access points and fixed client devices must not operate co-channel to
fixed microwave system frequencies within co-channel exclusion zones,
or on adjacent channel frequencies within adjacent channel exclusion
zones.
* * * * *
(7) * * *
(iii) Providing standard power access points and fixed client
devices with the permissible frequencies and the maximum permissible
power in each frequency range at their locations using propagation
models and interference protection criteria defined in paragraph (n) of
this section.
* * * * *
(l) Geofencing system. (1) A geofencing system must obtain
information on protected services within the 5.925-6.425 GHz and 6.525-
6.875 GHz bands from Commission databases and use that information to
determine frequency specific zones for geofenced variable power access
points and provide that information to those devices. These zones must
be determined for specified frequencies based on the propagation models
and protection criteria specified in paragraph (n) of this section.
(i) The zones can be determined as exclusion zones specifying
frequencies on which and locations where geofenced variable power
devices are not permitted to operate or inclusion zones specifying
frequencies on which and locations where geofenced variable power
devices are permitted to operate.
(ii) The geofencing system must assume that geofenced variable
power devices are at a height of 10 meters when determining exclusion
zones.
(iii) The geofencing system must access the Commission's licensing
databases and update the frequency-specific zones at least once per day
to ensure that they are based on the most recent information in the
Commission's databases.
(2) Geofencing systems must establish exclusion or inclusion zones
to prevent geofenced variable power access point operations between
6.525-6.875 GHz on the oceans beyond the United States territorial sea
as defined in 33 CFR 2.22(a)(1).
(3) The geofencing system must ensure that all communications and
interactions between the geofencing system and the geofenced variable
power access point and/or all communications between the geofencing
system and Commission databases are accurate and secure and that
unauthorized parties cannot access or alter the database or any
information it provides to geofenced variable power access points.
Additionally, the geofencing system must incorporate security measures
to protect against unauthorized data input or alteration of stored
data.
(4) A geofencing system must verify the validity of the FCC
identifier (FCC ID) of any geofenced variable power access point
seeking access to its services prior to authorizing the access point to
begin operation. A list of geofenced variable power access points with
valid FCC IDs and the FCC IDs of those devices must be obtained from
the Commission's Equipment Authorization System.
(5) A geofencing system must implement the terms of international
agreements with Mexico and Canada.
(6) With regard to enforcement instruction and data accuracy, each
geofencing system must:
(i) Ensure that a regularly updated geofencing system database that
contains the information described in this section, including
frequency-specific exclusion or inclusion zones and geofenced variable
power access points authorization parameters, is maintained.
(ii) Respond in a timely manner to verify, correct, or remove, as
appropriate, data in the event that the Commission or a party presents
a claim of inaccuracies in the geofencing system.
(iii) Establish and follow protocols to comply with enforcement
instructions from the Commission, including discontinuing geofenced
variable power access point operations on specified frequencies in
designated geographic areas and predetermined exclusion zones.
(iv) Comply with instructions from the Commission to adjust
frequency-specific exclusion or inclusion zones to more accurately
reflect the potential for harmful interference.
(7) A geofencing system operator must provide continuous service to
all geofenced variable power access points for which it has agreed to
provide service. If a geofencing system ceases operation, the operator
must provide at least 30 days' notice to the Commission and a
description of any arrangements made for those devices to continue to
receive location and frequency-specific update information.
(8) A geofencing system operator may charge fees for providing
service. The Commission may, upon request, review the fees and can
require changes to those fees if the Commission finds them to be
unreasonable.
(m) Geofenced variable power access point requirements. (1) A
geofenced variable power access point must register with and be
authorized by a geofencing system prior to the geofenced variable power
access point's initial service transmission. At registration the
geofenced variable power access point must provide its FCC identifier
(FCC ID) and either its unique manufacturer's serial number or its
model name/number or other information sufficient to uniquely identify
the device manufacturer and model.
[[Page 9168]]
(2) Geofenced variable power access point device geo-location
capability:
(i) A geofenced variable power access point must include an
internal geo-location capability to automatically determine the
geofenced variable power access point's geographic coordinates and
location uncertainty (in meters), with a 95% confidence level. The
geofenced variable power access point must use such coordinates and
location uncertainty when comparing the device's specific location to
frequency-specific information for its location obtained from the
geofencing system.
(ii) Geofenced variable power access point equipment authorization
applicants must provide an attestation describing the geo-location
method used, that method's accuracy, and the location uncertainty
accuracy.
(3) A geofenced variable power access point must access a
geofencing system to obtain frequency-specific information (i.e.,
exclusion zones or inclusion zones) for the area in which it is
operating or intends to operate (e.g., within a specific point radius
or within specific boundaries) prior to transmitting. If the geofenced
variable power access point moves beyond those boundaries, it must
obtain additional frequency-specific information for the new area and
adjust its operating frequency, if necessary, prior to operating in
this new area. If the geofenced variable power access point does not
obtain frequency specific information for the area in which it is
currently located, it may not transmit. The geofenced variable power
access point must obtain updated frequency-specific information from
the geofencing system at least once per day. If the geofenced variable
power access point fails to obtain the updated frequency specific
information on any given day, the geofenced variable power access point
may continue to operate until 11:59 p.m. of the following day at which
time it must cease operations until it can obtain updated frequency-
specific information for its location.
(4) A geofenced variable power access point must determine its
location and avoid transmitting on frequencies that are not available
in accordance with the frequency-specific information for its location
obtained from the geofencing system. The geofenced variable power
access point may not permit a client device operating under its control
to transmit on frequencies that are not available to the geofenced
variable power access point. The geofenced variable power access point
must determine its location frequently enough to ensure that it can
adjust its operating frequency, including ceasing operation, within one
second after any portion of the access point's location uncertainty
region crosses into an area in which its current operating frequency is
prohibited.
(5) A geofenced variable power access point must incorporate
adequate security measures to prevent it from accessing geofencing
systems not approved by the FCC, to ensure that unauthorized parties
cannot modify the device to operate in a manner inconsistent with the
rules and protection criteria set forth in this section, and to ensure
that communications between the geofenced variable power access point
and geofencing systems and between the geofenced variable power access
point and a client device operating under its control are secure to
prevent corruption or unauthorized interception of data.
(n) Incumbent protection by AFC and geofencing systems: Fixed
microwave services--(1) Propagation models. Propagation models to
determine the appropriate separation distance between a standard power
access point, a fixed client device, or geofenced variable power access
point and an incumbent fixed microwave service receiver. For a
separation distance:
(i) Up to 30 meters, the AFC system and geofencing system must use
the free space path-loss model.
(ii) More than 30 meters and up to and including one kilometer, the
AFC system and geofencing system must use the Wireless World Initiative
New Radio phase II (WINNER II) model. The AFC system or geofencing
system must use site-specific information, including buildings and
terrain data, for determining the line-of-sight/non-line-of-sight path
component in the WINNER II model, where such data is available. For
evaluating paths where such data is not available, the AFC system and
geofencing system must use a probabilistic model combining the line-of-
sight path and non-line-of-sight path into a single path-loss as
follows:
Equation 1 to Paragraph (n)(1)(ii)
Path-loss (L) = [Sigma]i P(i) * Li =
PLOS * LLOS + PNLOS * LNLOS
Where:
PLOS is the probability of line-of-sight.
LLOS is the line-of-sight path loss.
PNLOS is the probability of non-line-of sight.
LNLOS is the non-line-of-sight path loss.
L is the combined path loss.
The WINNER II path loss models include a formula to determine
PLOS as a function of antenna heights and distance.
PNLOS is equal to (1-PLOS).
In all cases, the AFC system and geofencing system will use the
correct WINNER II parameters to match the morphology of the path
between a standard power access point or geofenced variable power
access point and a fixed microwave receiver (i.e., Urban, Suburban, or
Rural).
(iii) More than one kilometer, the AFC system and geofencing system
must use Irregular Terrain Model (ITM) combined with the appropriate
clutter model. To account for the effects of clutter, such as buildings
and foliage, the AFC system and geofencing system must combine the ITM
with the ITU-R P.2108-0 (06/2017) clutter model for urban and suburban
environments and the ITU-R P.452-16 (07/2015) clutter model for rural
environments. The AFC system and geofencing system should use the most
appropriate clutter category for the local morphology when using ITU-R
P.452-16. However, if detailed local information is not available, the
``Village Centre'' clutter category should be used. The AFC system and
geofencing system must use 1 arc-second digital elevation terrain data
and, for locations where such data is not available, the most granular
available digital elevation terrain data.
(2) Interference protection criteria. (i) The AFC system and
geofencing system must use -6 dB I/N as the interference protection
criteria in determining the size of the co-channel zone where I
(interference) is the co-channel signal from the standard power access
point, geofenced variable power access point, or fixed client device at
the fixed microwave service receiver, and N (noise) is background noise
level at the fixed microwave service receiver.
(ii) The AFC system must use -6 dB I/N as the interference
protection criteria in determining the size of the adjacent channel
zone, where I (interference) is the signal from the standard power
access point or fixed client device's out of channel emissions at the
fixed microwave service receiver and N (noise) is background noise
level at the fixed microwave service receiver. The adjacent channel
zone must be calculated based on the emissions requirements of
paragraph (b)(7) of this section.
(3) Body loss. Geofencing systems may include up to 4 dB additional
loss to account for losses due to scattering and absorption from a
nearby body or object.
(o) Incumbent protection by AFC and geofencing systems: Radio
astronomy services. The AFC system and geofencing system must enforce a
zone to the following radio observatories that observe between 6650-
6675.2 MHz: Arecibo Observatory, the Green Bank Observatory, the Very
Large Array
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(VLA), the 10 Stations of the Very Long Baseline Array (VLBA), the
Owens Valley Radio Observatory, and the Allen Telescope Array. The zone
sizes are based on the radio line-of-sight and determined using 4/3
earth curvature and the following formula:
Equation 2 to Paragraph (o)
dkm_los = 4.12 * (sqrt(Htx) + sqrt(Hrx))
Where:
Htx is the height of the unlicensed standard power access point or
fixed client device.
Hrx is the height of the radio astronomy antenna in meters above
ground level.
Htx is 10 meters for an unlicensed geofenced variable power access
point.
Coordinate locations of the radio observatories are listed in Sec.
2.106(c)(131) and (385) of this chapter.
(p) Incumbent protection of fixed satellite services. Standard
power access points and fixed client devices located outdoors must
limit their maximum e.i.r.p. at any elevation angle above 30 degrees as
measured from the horizon to 21 dBm (125 mW) to protect fixed satellite
services.
[FR Doc. 2026-03744 Filed 2-24-26; 8:45 am]
BILLING CODE 6712-01-P