[Federal Register Volume 90, Number 43 (Thursday, March 6, 2025)]
[Rules and Regulations]
[Pages 11373-11388]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2025-02962]
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Rules and Regulations
Federal Register
________________________________________________________________________
This section of the FEDERAL REGISTER contains regulatory documents
having general applicability and legal effect, most of which are keyed
to and codified in the Code of Federal Regulations, which is published
under 50 titles pursuant to 44 U.S.C. 1510.
The Code of Federal Regulations is sold by the Superintendent of Documents.
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Federal Register / Vol. 90, No. 43 / Thursday, March 6, 2025 / Rules
and Regulations
[[Page 11373]]
FEDERAL COMMUNICATIONS COMMISSION
47 CFR Parts 2 and 15
[ET Docket No. 18-295, GN Docket No. 17-183; FCC 24-125; FR ID 275890]
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.
-----------------------------------------------------------------------
SUMMARY: In this document, the Federal Communications Commission
(Commission or FCC) expands unlicensed very low power (VLP) device
operation to the entire 6 gigahertz (GHz) band (5.925-7.125 megahertz
(MHz)). The VLP devices will operate with the same power levels and
other technical and operational requirements that apply to VLP devices
in the U-NII-5 (5.925-6.425 MHz) and U-NII-7(6.525-6.875 MHz) portions
of the 6 GHz band. These technical and operational requirements are
designed to prevent the licensed services that operate in the 6 GHz
band from experiencing harmful interference. The Commission's actions
will provide additional spectrum for high-throughput, low latency
operations for these versatile portable devices.
DATES: This final rule is effective May 5, 2025.
FOR FURTHER INFORMATION CONTACT: Nicholas Oros of the Office of
Engineering and Technology, at [email protected] or 202-418-0636.
SUPPLEMENTARY INFORMATION: This is a summary of the Commission's Third
Report and Order, in ET Docket No. 18-295, GN Docket No. 17-138, FCC
24-125, adopted on December 11, 2024, and released on December 13,
2024. The full text of this document is available for public inspection
and can be downloaded at https://docs.fcc.gov/public/attachments/FCC-24-125A1.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 prepare a regulatory
flexibility analysis for notice-and-comment rulemaking, 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
and policy changes contained in the Third Report and Order on small
entities. The FRFA is set forth in Appendix B, https://docs.fcc.gov/public/attachments/FCC-24-125A1.pdf.
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 Third Report and Order to Congress
and the Government Accountability Office pursuant to 5 U.S.C.
801(a)(1)(A).
Synopsis
Introduction
In 2020, the Commission adopted rules making unlicensed device
access to 1200 megahertz across the 6 GHz band (5.925-7.125 GHz) more
flexible, resulting in increased unlicensed device usage. These rules
unleashed a torrent of new devices taking advantage of the newer Wi-Fi
6 and 6E standards to provide users across the U.S. with a better Wi-Fi
user experience. More recently, in 2023, the Commission expanded 6 GHz
band unlicensed use to permit an additional class of unlicensed access
points--very low power (VLP) devices. VLP devices are intended to
provide high data rate connections across short distances.
The Commission expands unlicensed VLP device operation to the
entire 6 GHz band. This will provide additional spectrum for high-
throughput, low latency operations for these versatile portable
devices. Specifically, the Commission's actions pave the way for these
devices to use the latest standards and to take advantage of larger
channels across the 6 GHz band. The Commission expects that VLP devices
will be instrumental in supporting cutting-edge applications, such as
augmented and virtual reality and body-worn technologies, that will
help businesses, enhance learning opportunities, advance healthcare
opportunities, and bring new entertainment experiences. As the
Commission expands the spectrum available for VLP devices, it adopts
the same power levels and other technical and operational requirements
that apply to VLP devices in the U-NII-5 and U-NII-7 portions of the 6
GHz band, which are designed to prevent the licensed services that
operate in the 6 GHz band from experiencing harmful interference. In
this way, the Commission facilitates more intensive use of its valuable
spectrum resources, thereby enabling exciting new technologies to be
deployed to American consumers, while ensuring that incumbent services
are protected from harmful interference.
Background
The 6 GHz band has allocations for the Fixed Service, Mobile
Service, and Fixed Satellite Service (FSS) across four sub-bands. These
four sub-bands--which the Commission refers to as U-NII-5, U-NII-6, U-
NII-7, and U-NII-8, respectively--are delineated based on the
prevalence and characteristics of the incumbent licensed services that
operate in each sub-band as denoted in table 1. Fixed microwave service
licensees, specifically those operating point-to-point microwave links
that support a variety of critical services provided by utilities,
commercial and private entities, and public safety
[[Page 11374]]
agencies, are the largest user group in the 6 GHz band. These fixed
microwave service licensees make significant use of the U-NII-5 and U-
NII-7 bands, and also operate in relatively smaller numbers in the U-
NII-8 band. The microwave links provide backhaul for commercial
wireless providers (such as traffic between commercial wireless base
stations and wireline networks), coordinate railroad train movements,
control natural gas and oil pipelines, manage electric grids, as well
as carry long-distance telephone calls.
Table 1--Predominant Licensed Uses of the 6 Gigahertz Band
----------------------------------------------------------------------------------------------------------------
Frequency range Predominant licensed
Sub-band (GHz) Primary allocation services
----------------------------------------------------------------------------------------------------------------
U-NII-5............................. 5.925-6.425 Fixed..................... Fixed Microwave.
FSS....................... FSS (uplinks).
U-NII-6............................. 6.425-6.525 Mobile.................... Broadcast Auxiliary
FSS....................... Service.
Cable Television Relay
Service.
FSS (uplinks).
U-NII-7............................. 6.525-6.875 Fixed..................... Fixed Microwave.
FSS....................... FSS (uplinks/downlinks).
U-NII-8............................. 6.875-7.125 Fixed..................... Fixed Microwave.
Mobile.................... Broadcast Auxiliary
FSS....................... Service.
Cable Television Relay
Service.
FSS (uplinks/downlinks)
(6.875-7.075 GHz only).
----------------------------------------------------------------------------------------------------------------
The Broadcast Auxiliary Service (BAS) and Cable Television Relay
Service (CARS) operate in the U-NII-6 band on a mobile basis, and in
the U-NII-8 band on both a fixed and mobile basis. Licensees use BAS
and CARS pick-up stations to transmit programming material from special
events or remote locations, including electronic news gathering, back
to the studio or other central receive locations. Television broadcast
related microwave links, such as television studio transmitter links,
television inter-city relay links, and television translator relay
links, operate primarily one-way point-to-point systems in the U-NII-8
band. Additionally, Low Power Auxiliary Stations (i.e., wireless
microphones), which operate on an itinerant basis, are authorized to
operate in the U-NII-8 band on a secondary basis for uses such as
portable cameras, wireless microphones, cues, and backstage
communications.
The Fixed Satellite Service (FSS) is allocated in the Earth-to-
space direction in all four sub-bands, except for the 7.075-7.125 GHz
portion of the U-NII-8 band. FSS operations are heaviest in the U-NII-5
band, which is paired with the 3.7-4.2 GHz frequency band in the space-
to-Earth direction to comprise the ``conventional C band.'' Predominant
FSS uses of these frequencies include content distribution to
television and radio broadcasters, including transportable antennas to
cover live news and sports events, cable television and small master
antenna systems, and telephone and data backhaul traffic. The 7.025-
7.075 GHz portion of the U-NII-8 band also hosts feeder uplinks to
Satellite Digital Audio Radio Service space stations. Additionally,
portions of the UNII-7 and U-NII-8 bands are allocated for FSS space-
to-Earth operations for Mobile-Satellite Service feeder links between
6.700 GHz and 7.075 GHz. In addition to these licensed incumbent
services, an international footnote in the table of frequency
allocations urges that the Commission takes ``all practicable steps''
to protect the radio astronomy service in the 6650-6675.2 MHz range
from harmful interference. Finally, low-power unlicensed ultra-wideband
(UWB) and wideband systems operate in the 6 GHz band under the
Commission's part 15 rules. Like all other part 15 devices, UWB and
wideband devices operate on a non-interference basis and must accept
interference from and are not permitted to cause harmful interference
to authorized stations.
On April 23, 2020, the Commission adopted a Report and Order (6 GHz
First Order), 85 FR 31390 (May 26, 2020), that expanded unlicensed
operations in the 6 GHz band (5.925-7.125 GHz). The 6 GHz First Order
adopted rules for two categories of unlicensed operations--standard-
power operations and low-power indoor (LPI) operations. Standard-power
access points and fixed client devices are limited to two portions of
the 6 GHz band--the U-NII-5 band (5.925-6.425 GHz) and the U-NII-7 band
(6.525-6.875 GHz)--and are required to operate under the control of an
automated frequency coordination (AFC) system. Low-power indoor access
points can operate across the entire 6 GHz band, but at lower power
levels than standard power operations, and must incorporate a
contention-based protocol. Client devices operate under the control of
either a standard-power or low-power indoor access point and
communicate using power levels that depend on the type of access point
to which they are connected.
On November 1, 2023, the Commission released a Second Report and
Order, 89 FR 874 (January 8, 2024), that allowed unlicensed very low
power (VLP) devices to operate in the U-NII-5 and U-NII-7 portions of
the 6 GHz band (6 GHz Second Order). The VLP devices are authorized to
operate anywhere, indoors and outdoors, without being under the control
of an AFC system. The VLP devices are limited to power levels that
allow them to coexist with incumbent operations in the band: 14
decibel-milliwatts (dBm) equivalent isotropic radiated power (EIRP) and
a -5 dBm/MHz EIRP power spectral density. VLP devices are also required
to employ a transmit power control mechanism that has the capability to
operate at least 6 dB below the -5 dBm/MHz EIRP power spectral density
(PSD) level and must employ a contention-based protocol. VLP devices
are prohibited from operating as part of a fixed outdoor
infrastructure, such as poles or buildings. Also, VLP devices are
required to prioritize operations above 6105 MHz prior to operating on
frequencies between 5925 MHz and 6105 MHz to ensure that services below
the U-NII-5 band are protected from potential harmful interference. In
the 6 GHz Second Order, the Commission required emissions from VLP
devices in the U-NII-5 and U-NII-7 bands to comply with the
transmission emission mask adopted in the 6 GHz First Order. The power
spectral density must be suppressed by 20 dB at one megahertz outside
of an unlicensed device's channel edge, suppressed by 28 dB at one
channel bandwidth from an unlicensed device's channel center, and
suppressed by 40 dB at one and one-half
[[Page 11375]]
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 must be 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 must be linearly interpolated between the 28 dB
and 40 dB suppression levels. 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-7 bands, must be suppressed by at least 40 dB.
The Commission is adopting the same emission limits for VLP devices
operating in the U-NII-6 and U-NII-8 bands. For emissions limits at the
edge of the U-NII-5 and U-NII-8 bands, 6 GHz VLP devices must comply
with 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). Consistent with the rules adopted in the 6 GHz Second
Order for LPI and standard power devices, VLP devices will be
prohibited from operating in low flying aircraft and unmanned aircraft
systems. For aircraft above 10,000 feet, VLP devices can operate across
the 5.925-6.425 GHz band. The Commission will also continue to prohibit
VLP devices from operating on oil platforms. Similarly, in the 6 GHz
Second Order, VLP devices will continue to be permitted to operate on
boats.
In the Second Further Notice of Proposed Rulemaking (6 GHz Second
FNPRM), 89 FR 14015 (February 26, 2024), adopted concurrently with the
6 GHz Second Order, the Commission proposed to expand VLP operation to
the U-NII-6 (6.425-6.525 GHz) and U-NII-8 (6.875-7.125 GHz) portions of
the 6 GHz band, with no requirement that the devices be kept indoors or
be under the control of an AFC system. The 6 GHz Second FNPRM also
proposed to permit VLP operation at higher power levels while under the
control of a geofencing system. The geofencing system would utilize
Commission databases to create exclusion zones to protect incumbent
licensed services. In addition, because the current 6 GHz unlicensed
rules prohibit direct communication between client devices, the 6 GHz
Second FNPRM sought comment on allowing such communications between
client devices to 6 GHz unlicensed low-power indoor access points. In
the Third Report and Order, the Commission only addresses the 6 GHz
Second FNPRM proposal to expand VLP operation to the U-NII-6 and U-NII-
8 portions of the 6 GHz band while deferring the remaining issues to
future Commission actions.
The Commission received comments from numerous parties in favor of
allowing unlicensed VLP operations in the 6 GHz band, as well as from
parties representing the interests of incumbent licensees raising
concerns about potential harmful interference from the proposed
unlicensed VLP operations in the U-NII-6 and U-NII-8 bands. In response
to the 6 GHz Second FNPRM, 6 GHz band unlicensed device proponents--
including Apple, Broadcom, Google, Intel Corporation, Meta Platforms,
Microsoft Corporation, Qualcomm, the Wi-Fi Alliance, the Wireless
Broadband Alliance, the Japan Electronics and Information Technology
Industries Association, and the Consumer Technology Association (CTA)--
support the Commission's proposal for authorizing unlicensed VLP device
operations across the 6 GHz band. They emphasize that such operations
will support a host of immersive, real-time applications in areas such
as healthcare, high accuracy location, advanced connectivity,
innovative game experiences, and augmented reality/virtual-reality
devices, among other uses. CTA points out that providing high-speed
connections for some of the most advanced applications, including
wearables and augmented and virtual reality (AR/VR), will help
businesses, enhance learning opportunities, advance healthcare
opportunities, and bring new entertainment experiences. Several
commenters also assert that technical rules can be established to
protect incumbent spectrum users from harmful interference. Apple,
Broadcom, et al. submitted several technical studies to support their
contention that VLP devices will not cause harmful interference to
licensed incumbent users.
Commenters representing incumbent users express various concerns
about the potential for harmful interference to their operations from
unlicensed VLP operations. Commenting parties include the National
Public Safety Telecommunications Council on behalf of public safety
microwave incumbents, Sirius XM Radio, the National Association of
Broadcasters (NAB) on behalf of local radio and television stations and
broadcast networks, and the National Academy of Sciences' Committee on
Radio Frequencies regarding radio astronomy observatories. In its
comment, Electric Power Research Institute (EPRI) states that incumbent
microwave operators will incur significant costs in trying to locate
VLP interference sources if the protection scheme is ineffective in
providing adequate protection. According to EPRI, ``VLP sources being
outdoor and portable or vehicular mobile[ ] will make locating the
offending device extremely difficult if not impossible.'' MEMA, The
Vehicle Suppliers Association, also expressed interference concerns in
its filing, pointing out that higher transmitting power in VLP devices
could ``increase the potential for interference with vehicle safety
systems communications.''
Discussion
The Commission adopts rules to permit VLP devices to operate across
the U-NII-6 and U-NII-8 portions of the 6 GHz band at the same power
levels the Commission adopted for VLP operations in the U-NII-5 and U-
NII-7 bands: -5 dBm/MHz EIRP power spectral density (PSD) and 14 dBm
EIRP. This will expand the spectrum available for VLP devices to 1200
megahertz, thereby permitting the use of up to seven 160-megahertz
channels or three 320-megahertz channels. VLP devices will enable new
innovative uses and will provide opportunities to enhance nascent
applications, such as augmented reality/virtual reality, in-car
connectivity, wearable on-body devices, healthcare monitoring, short-
range mobile hotspots, high accuracy location and navigation, and
automation. The rules the Commission is adopting are designed to
support innovation to bring exciting new applications to market while
protecting the important licensed services that operate in the U-NII-6
and U-NII-8 portions of the 6 GHz band from harmful interference. The
Commission concludes that VLP operation at the power levels they are
permitting will have an insignificant potential for causing harmful
interference to licensed users of the band.
In expanding VLP operations to the U-NII-6 and U-NII-8 portions of
the 6 GHz band, the Commission is adopting the same rules that it
previously adopted for VLP devices operating in the U-NII-5 and U-NII-7
bands. For example, VLP devices in the U-NII-6 and U-NII-8 bands must
operate at the same power levels, employ a contention-based protocol,
and implement transmit power control.
[[Page 11376]]
Protecting Mobile Services
The U-NII-6 and U-NII-8 bands are used for electronic newsgathering
(ENG) and other video broadcasting-related applications by licensees
operating under the part 74 broadcast auxiliary services, part 78 Cable
Television Relay Service, and part 101 Local Television Transmission
Service. Additionally, Low Power Auxiliary Stations (i.e., wireless
microphones), which operate on an itinerant basis, are authorized to
operate in the U-NII-8 band on a secondary basis for uses such as
portable cameras, wireless microphones, cues, and backstage
communications. The 6 GHz Second FNPRM specifically requested
information on three categories of mobile 6 GHz band equipment: (i)
outdoor ENG central receive sites; (ii) outdoor ENG truck receivers
(transmissions from portable cameras and microphones to a receiver on a
truck); and (iii) low-power short range mobile devices. Commenters in
response to the 6 GHz Second FNPRM discussed the interference potential
of VLP devices to outdoor ENG central receive sites and transmissions
from portable cameras to outdoor ENG truck receivers. No commenters
provided feedback regarding other types of mobile 6 GHz equipment or
use scenarios, such as low-power short range mobile devices. Because no
commenters have raised concerns or suggested other use cases, the
Commission directs its examination of the potential for VLP devices to
cause harmful interference to mobile applications to the three specific
use cases discussed in the 6 GHz Second FNPRM. As discussed in more
detail below, the Commission concludes that there is an insignificant
risk that VLP device operation in the U-NII-6 and U-NII-8 bands will
cause harmful interference to licensed mobile operations for these use
cases.
Limiting its discussion to these three use cases closely mirrors
the approach the Commission followed when adopting rules to permit
unlicensed 6 GHz band low-power indoor devices to operate in the U-NII-
6 and U-NII-8 bands. For low-power indoor devices, the Commission
considered three distinct use cases as representative of mobile use of
those portions of the 6 GHz band: (i) an ENG truck transmitting to a
central receive site; (ii) portable cameras transmitting to an outdoor
ENG truck receiver; and (iii) portable cameras transmitting to an
indoor receive site. These were the three use cases that were examined
in an engineering study conducted by Alion (Alion Study) that was
provided by NAB. The first two of these use cases are identical to the
cases in the 6 GHz Second FNPRM, while the 6 GHz Second FNPRM discusses
a slightly broader third case. Given the Commission's past approach to
considering the interference potential of 6 GHz unlicensed devices to
mobile operations, the Commission believes that discussing the three
use cases raised in the 6 GHz Second FNPRM adequately addresses mobile
operations in the band.
ENG Central Receive Sites
The communications link between ENG trucks and a central receive
site shares many of the characteristics of a fixed microwave link.
Specifically, the link uses directional antennas to send signals
between two fixed locations that are mostly above the local clutter.
The 6 GHz Second FNPRM proposed to permit VLP devices to operate in the
U-NII-6 and U-NII-8 bands and sought comment on whether VLP devices
could operate at up to -5 dBm/MHz EIRP PSD and 14 dBm EIRP in those
bands while keeping the risk of harmful interference to ENG central
receive sites to an insignificant level. The 6 GHz Second FNPRM also
sought comment on whether the same type of analysis discussed in the 6
GHz Second Order showing an insignificant harmful interference risk to
fixed microwave receive sites would be appropriate with respect to ENG
central receive sites, or whether there are inherent differences
between BAS/CARS operations as compared to fixed point-to-point
operations that must be considered when analyzing the harmful
interference risk, e.g., differences in antenna beamwidth and gain,
typical antenna heights or receive antenna locations.
NAB expresses concerns about potential interference to ENG central
receive sites from VLP devices in the U-NII-6 and U-NII-8 bands. In
making its comments, NAB considered a study filed by Apple, Broadcom,
et al. on September 11, 2023, which found that VLP devices would not
cause harmful interference to ENG central receive sites. NAB concedes
that ``in a Monte Carlo analysis that relies on reasonable assumptions,
some number, even a large number, of simulations might yield no
degradation or interference to an ENG receiver,'' but states that
Apple, Broadcom, et al.'s claim of absolutely no interference to ENG
receivers, ever, is ``plainly and facially unreasonable.'' NAB states
that ``[m]any hypothetical VLP transmitters located near [an] ENG
receive antenna would certainly present signals exceeding -6 dB above
the receiver noise floor,'' and argues as an example that the
Washington, DC Old Post Office site considered in the Alion Study would
have a received signal level 34 dB above the -6 dB interference-to-
noise (I/N) criterion from a VLP device located 500 meters away. NAB
disputes Apple, Broadcom, et al.'s claim that `` `ENG links typically
are configured to operate with a significantly higher signal-to-noise
ratio than needed to successfully operate,' '' stating that this is
``unfounded and inaccurate'' because ``ENG links are not `configured'
to operate in some excessive or overengineered manner . . . and often
operate within a few dB of failure.''
On June 28, 2024, Apple, Broadcom, and Meta submitted an additional
study performed by RKF Engineering (RKF) on the potential for
interference from VLP devices to ENG central receive sites in the 6 GHz
band. RKF performed a Monte Carlo analysis with 100,000 iterations over
the contiguous United States to investigate the likelihood of harmful
interference to ENG central receiver sites from VLP devices in the U-
NII-6 and U-NII-8 bands. A Monte Carlo simulation uses random sampling
and statistical modeling to estimate mathematical functions and mimic
the operations of complex systems. The simulation examined all 567 ENG
central receive sites listed in the FCC's Universal Licensing System
for the continental United States as a representative sample of all ENG
central receive sites. RKF states that ``[t]he analysis demonstrates
that the risk that VLP devices will cause exceedances of -6 dB I/N is
extremely low,'' and is in fact ``lower than [in] other scenarios where
the Commission has determined that sharing between 6 GHz [Radio Local
Area Network (RLAN)] devices and incumbent licensees presented an
`insignificant' risk of harmful interference by the FCC's definition.''
It states that 95% of ENG receive sites ``had no exceedance over
100,000 simulation iterations,'' and that ``[t]he risk of harmful
interference from VLP devices to [ENG receive sites] was exceedingly
small with a 0.0001% average probability of an exceedance across all
[ENG receive sites].''
On November 7, 2024, Apple, Broadcom, et al. submitted updated
results for the June 28, 2024, study. NAB pointed out that it might be
possible that the June 28, 2024, study had inverted the antenna pattern
for the ENG central receive sites to have positive gain above the
horizon instead of below the horizon. Apple, Broadcom, et al. agreed
with NAB that the antenna pattern used in the June 28, 2024, study was
incorrect and submitted new simulation results with the antenna
[[Page 11377]]
pattern correctly implemented. The revised simulation indicates the
probability of exceeding -6 dB I/N across all ENG central receive sites
was 0.0005%, which Apple, Broadcom, et al. contend is below what the
Commission found to be acceptable for low-power indoor operation in the
U-NII-6 and U-NII-8 bands. The revised simulation also indicates that
the probability of exceeding -6 dB I/N for the ENG receive site with
the highest probability of exceedance increased from 0.007% to 0.009%,
which Apple, Broadcom, et al. point out is much lower than the 0.04%
exceedance probability for the worst-case link in the San Francisco
study that the Commission relied on in the 6 GHz Second Order.
The Commission finds that the June 28, 2024, computer simulations
based on Monte Carlo analysis submitted by Apple, Broadcom, and Meta,
as corrected by the Apple, Broadcom, et al. November 7, 2024, filing,
provides sufficient support for permitting VLP operation at up to -5
dBm/MHz EIRP power spectral density (PSD) and 14 dBm EIRP across the U-
NII-6 and U-NII-8 portions of the 6 GHz band. Relying on this computer
simulation is consistent with a directive the Commission made in a 2023
Policy Statement to follow a data-driven approach to spectrum
management rather than placing dispositive weight on worst-case
examples that may be rare or never occur in practice. Relying on Monte
Carlo computer simulations is also consistent with the Commission's
previous actions in adopting rules for unlicensed 6 GHz low-power
indoor devices and for VLP devices in the U-NII-5 and U-NII-7 bands.
For the low-power indoor device rules, the Commission characterized a
Monte Carlo computer simulation submitted by CableLabs as ``the best
evidence in the record of the impact that unlicensed low-power indoor
devices will have on incumbent operations,'' and for the VLP rules the
Commission found that Monte Carlo computer simulations submitted by
Apple, Broadcom, et al. and by Apple provided sufficient support for
permitting VLP operation in the U-NII-5 and U-NII-7 bands.
The Commission previously found that a well-designed computer
simulation can simultaneously model many probabilistic factors that
determine whether harmful interference may occur. In the case of ENG
central receive sites in the U-NII-6 and U-NII-8 bands, these factors
include VLP device location variability in relation to the ENG
receiver, height of the VLP device, whether the VLP device is operating
co-channel to the ENG receiver, the VLP power level, and the radio
propagation environment. In examining the potential for harmful
interference to occur to ENG central receive sites from VLP devices,
the characteristics of the receivers and antennas must also be
considered. ENG central receive sites use directional antennas
typically located on tall towers or building rooftops, but unlike fixed
microwave antennas their directivity may be variable to accommodate ENG
signals from multiple directions. In addition, other factors that
affect the potential for VLP devices to cause harmful interference
include body loss, the use of transmit power control (TPC), and antenna
polarization mismatch.
Based on Apple, Broadcom, and Meta's June 28, 2024, study, as
corrected by the Apple, Broadcom, et al. November 7, 2024, filing, the
Commission concludes that there is an insignificant risk of harmful
interference occurring to ENG central receiver sites from VLP devices
operating in the U-NII-6 and U-NII-8 bands. This simulation provides a
detailed description of all the assumptions used in performing a Monte
Carlo analysis to determine the likelihood of harmful interference to
ENG central receive sites from VLP devices operating in the U-NII-6 and
U-NII-8 bands. With the exception of certain assumptions specific to
ENG central receive sites described below, it uses the same assumptions
as the San Francisco simulation that the Commission relied upon in the
6 GHz Second Order when it adopted rules for VLP devices in the U-NII-5
and U-NII-7 bands. It assumes a -5 dBm/MHz PSD VLP EIRP and a 14 dBm
maximum EIRP, power reduction from TPC based on a Gaussian distribution
with a 3 dB mean that is truncated at 0 dB and 6 dB, body loss based on
a Gaussian distribution with a 4 dB mean that is truncated at 0 dB and
8 dB, and a VLP device height of 1.5 meters in 90% of cases with higher
elevation (e.g., on balconies) in 10% of cases. To determine the number
of active VLP devices in each simulation iteration, the study used the
same assumptions as for the San Francisco study regarding the
percentage of people outdoors (6%), the percentage of people outdoors
using VLP devices (25%), the percentage of VLP devices operating in
unlicensed bands (90%), the percentage of those devices capable of
using the 6 GHz band (50%), the percentage of the devices actually
using the 6 GHz band (65%), and the percentage of devices actively
transmitting at any instant (2%). Multiplying these percentages by the
total United States population results in 29,661 active VLP devices for
each iteration. The study also used the same propagation models
previously specified by the Commission and used in prior studies, i.e.,
free space path loss at distances less than 30 meters, WINNER II line-
of-sight (LOS) at distances between 30 meters and 50 meters, WINNER II
Combined LOS/non-LOS (NLOS) at distances between 50 meters and 1
kilometer, and Irregular Terrain Model (ITM) at distances greater than
1 kilometer.
Apple, Broadcom, and Meta's June 28, 2024, study used ENG receive
site antenna information for the 567 receive sites listed in the
Commission's Universal Licensing System (ULS), specifically, the center
frequency, bandwidth, location, antenna height above ground, and
maximum antenna gain. In analyzing the ULS data, RKF discovered that 99
of these sites had an apparently erroneous antenna height of exactly
6.1 meters listed when in fact the antenna height was much greater
because it was mounted on a building or tall tower. RKF believed that
it was more appropriate to perform the analysis by excluding the sites
with apparently erroneous antenna height information, but also provided
results showing the effect of including these sites. Apple, Broadcom,
and Meta's June 2024 study uses the same parameters and assumptions as
NAB's Alion Study for ENG central receive sites, specifically, Vislink
ProScan III antenna patterns (azimuth and elevation), a 4 dB receiver
noise figure, and a 1 dB feeder loss.
Apple, Broadcom, and Meta's June 28, 2024, study, as corrected by
the Apple, Broadcom, et al. November 7, 2024, filing, shows that the
average probability of exceeding the -6 dB I/N interference protection
criterion in a given iteration is only 0.0005% per central receive
site. Further, the study showed the worst-case probability for a single
receive site to exceed this metric is only 0.009%. Based on the results
of this study, which uses assumptions and parameters that are
consistent with those the Commission previously accepted, the
Commission finds that the risk of harmful interference to ENG central
receive sites is insignificant. The Commission notes that these results
showing an extremely low harmful interference likelihood are consistent
with those of the September 11, 2023, study submitted by Apple,
Broadcom, et al., which analyzed the potential for interference from
VLP devices at two ENG central receive sites. The Commission recognizes
the limitations of Apple, Broadcom, and Meta's latest analysis in that
not every ENG central
[[Page 11378]]
receive site is listed in the ULS, but the Commission believes that the
sample size is large enough to represent the harmful interference
potential of VLP devices in the U-NII-6 and U-NII-8 bands. Regardless
of whether the analysis includes or excludes the 99 receive sites
listed in the ULS that have apparently incorrect height information,
the Commission's conclusion is the same in that the likelihood that the
-6 dB I/N ratio will be exceeded at ENG central receive sites is very
low and presents only an insignificant harmful interference risk.
NAB takes issue with several aspects of Apple, Broadcom, and Meta's
June 28, 2024, study. NAB faults the study for placing VLP devices at
locations throughout the entire contiguous United States, which it
notes includes locations more than 30 kilometers from ENG central
receive sites. NAB claims that interference would not be possible at
such distances. NAB also claims that the study does not include enough
active VLP devices in each iteration. It points out that by using only
approximately 30,000 VLP devices across the contiguous United States,
it only evaluates potential interference from an average of one device
in every 100 square miles. The Commission disagrees with NAB regarding
the merit of its criticism. Apple, Broadcom, and Meta's June 28, 2024,
study, as corrected by the Apple, Broadcom, et al. November 7, 2024,
filing, provides I/N statistics at ENG central receive sites resulting
from VLP operations. The Commission believes that the methodology
employed, which randomly placed the active VLP devices based on
population density, was appropriate for evaluating the potential
interference environment to generate these I/N statistics. The study
used appropriate assumptions to determine that 30,000 VLP devices will
be transmitting at a time. As noted, active VLP devices were placed
based on population density, and because the study accounts for
receivers in densely populated areas, the number of active VLP devices
near ENG central receive sites evaluated during each iteration is
likely to be far higher than NAB's calculated average. The Commission
agrees with Apple, Broadcom, et al. that the inclusion of VLP devices
in the simulation that are distant from ENG central receive sites does
not change the properly modeled density of VLP devices close to the ENG
central receive sites, which is based on user density. Thus, NAB's
argument does not reflect the nature of how VLP devices were actually
placed for evaluation. Relatedly, the Commission also notes that the
fact that many VLP devices will not be located within 30 kilometers of
an ENG central receiver site reflects the reality that the majority of
VLP devices active at any given time will not be operating near these
locations.
The Commission disagrees with NAB's contention that a VLP device
operating at 500 meters from the Old Post Office Building in
Washington, DC would produce a received signal level that exceeds the -
6 dB I/N threshold by 34 dB at an ENG receiver located there. The
Commission reiterates that exceeding a -6 dB I/N does not constitute
harmful interference, rather, if the probability of exceeding this
level is extremely low, then the probability of actual harmful
interference is insignificant. NAB does not describe how it calculated
its result, but based on the magnitude the Commission believes that NAB
used a methodology inconsistent with previous Commission orders,
resulting in an unrealistically high I/N ratio. Its result appears to
be consistent with the use of free-space propagation modeling, whereas
the Commission previously rejected free-space propagation modeling at
distances greater than 30 meters, stating that free space propagation
has limited applicability beyond that distance because it ignores
environmental clutter and over long distances can result in extremely
conservative calculations that under predict the amount of actual path
loss. The Commission found that the WINNER II model is more appropriate
for distances between 30 meters and 1 kilometer because it accounts for
obstructions from urban and suburban clutter, which the free space
model does not. Also, NAB's stated value of -104 dBm/10 MHz for ENG
receiver sensitivity appears to be too low. The Commission calculates
that this level would be the thermal noise floor of a receiver with a
10 megahertz bandwidth, meaning it does not include the receiver noise
figure. The Alion Study specifies that a receiver noise figure of 4 dB
along with a line loss of 1 dB should be included in calculating
potential interference to ENG receivers. Additionally, NAB failed to
include other mitigating factors that the Commission previously found
were appropriate, specifically, 3 dB for TPC, 4 dB for body loss, 3 dB
for antenna polarization mismatch, and 5 dB for antenna pattern
mismatch. Taking all these factors into account, the Commission
calculates that the received signal strength in NAB's example would be
-129 dBm, compared to a receiver noise floor of -100 dBm (including
noise figure), significantly less than the -6 dB I/N metric.
In sum, Apple, Broadcom, and Meta's latest study performed in the
same manner and using the same assumptions as previous studies (with
the exception of those specific to ENG receivers) that the Commission
found acceptable for permitting VLP devices in the U-NII-5 and U-NII-7
bands shows that the likelihood of VLP devices in the U-NII-6 and U-
NII-8 bands exceeding -6 dB I/N at an ENG central receive site is
extremely low. In addition, the Commission's calculations show that
even in what NAB indicates would be a worst-case scenario, a VLP device
would likely not exceed -6 dB I/N. Thus, the Commission concludes that
the risk of harmful interference from VLP devices to ENG central
receive sites in the U-NII-6 and U-NII-8 bands is insignificant.
Because this interference risk is so low in the absence of any of the
additional factors or mitigation measures suggested by Apple, Broadcom,
et al. that could further reduce the likelihood of harmful interference
(i.e., that links have a significantly higher signal-to-noise ratio
than needed to successfully operate, the locations of ENG trucks can be
moved to get a better line of sight to a fixed receive site, and ENG
power levels can be increased), the Commission does not address NAB's
arguments on the validity of the Apple, Broadcom, et al.'s statements.
NAB's points regarding interference matters in other bands and
outside the record of this proceeding do not add support to its claims
of potential interference described here, and the Commission has
adequately addressed those for purposes of this rulemaking.
Specifically, NAB claims that it has repeatedly demonstrated that
broadcasters have lost access to licensed spectrum in the 2.4 GHz band
``due to ruinous interference from unlicensed devices'' that ``has
continued unabated for nearly 25 years.'' The Commission has previously
concluded that the record in this proceeding ``contains no substantial
evidence of harmful interference to broadcast operations in the 2.4 GHz
band'' and noted the absence of interference complaints regarding the
2.4 GHz band. No commenter to this proceeding offers new information
regarding such interference claims, and the Commission declines to
revisit them on its own motion. NAB also contends that even when
interference occurs among licensed users, such as alleged interference
to private land mobile systems in spectrum bands shared with broadcast
television stations, the
[[Page 11379]]
Commission has not consistently investigated or resolved these
conflicts. NAB claims that rather than take action to resolve these
longstanding interference problems, the Commission has demurred.
According to NAB, this past FCC inaction raises concerns that if the
risk of interference is not addressed now it will go unaddressed in the
future. The Commission takes seriously its responsibility to prevent
harmful interference from occurring. The Commission has concluded that
permitting VLP devices to operate in the U-NII-6 and U-NII-8 bands will
present an insignificant harmful interference risk to licensed mobile
operations. Therefore, the Commission has adequately addressed NAB's
interference concerns and NAB's allegations concerning the Commission's
inaction regarding interference in other bands do not provide grounds
to alter its course. Nonetheless, the Commission also remains committed
to resolving harmful incidents in the unlikely possibility that they
occur.
ENG Truck Receivers
Electronic newsgathering (ENG) trucks are generally situated near a
news or sporting event and receive signals from hand-held cameras or
other portable news gathering equipment. According to the Alion Study
previously submitted by NAB, the ENG truck receive antenna may be omni-
directional or sectoral with adjustable height from 5 to 50 feet and
the signals may use various bandwidths between 3 and 20 megahertz. The
6 GHz Second FNPRM proposed to permit VLP devices to operate in the U-
NII-6 and U-NII-8 bands and sought comment on whether the devices can
operate at up to -5 dBm/MHz EIRP PSD and 14 dBm EIRP while minimizing
the risk of harmful interference to ENG truck receivers. The 6 GHz
Second FNPRM asked what is the appropriate metric for evaluating the
harmful interference risk to an ENG truck receiver; if signal-to-
interference-plus-noise ratio (SINR) is used as a metric what value or
range of values should be used; and is there a connection between
reliance on an I/N metric for evaluating ENG trucks connecting to a
central receive site and evaluating the risk to a truck receiver based
on SINR. The 6 GHz Second FNPRM also requested information on the
typical bandwidth and coding rates used by ENG truck receivers and how
close a random VLP device can come to a ENG truck receiver under normal
operating conditions.
According to Apple, Broadcom, et al., a SINR of 1 dB is necessary
for the link between a camera and a portable ENG truck receiver to
operate without harmful interference. As described in their comments,
the parties base this claim on empirical SINR measurements that
Broadcom previously submitted showing the level necessary to maintain
an error-free video signal for different signal bandwidths, coding
rates, and unlicensed device activity factors. These measurements show
that there would be no audio or video defects with an SINR of at least
1 dB for an unlicensed device activity factor of 2% and a video signal
of 10 megahertz bandwidth. Apple, Broadcom, et al. note that the 6 GHz
First Order relied on these Broadcom measurements in authorizing low-
power indoor operations in the U-NII-6 and U-NII-8 bands. Apple,
Broadcom, et al. claim that while the Commission, in the 6 GHz First
Order, discussed studies that apply a 10 dB SINR threshold for
interference, it did not adopt this 10 dB SINR as an interference
threshold. Instead, they note that the Commission observed that the
Broadcom measurements found `` `that for a 10% activity factor the
[ENG] link required a signal-to-interference-plus-noise of between 2
and 9 dB.' '' Apple, Broadcom, et al. point out that the Commission has
more recently determined that a more realistic 2% activity factor
should be assumed for VLP devices. Therefore, they claim that
Broadcom's measurements demonstrate that with a VLP duty cycle of 2%,
the portable equipment to ENG truck receiver link only requires an SINR
of 1 dB. Apple, Broadcom, et al. also suggest that assuming
broadcasters would use a 10 megahertz bandwidth signal rather than an 8
megahertz bandwidth signal is more realistic as this would be more
robust and support higher throughput. But, even with an 8 megahertz
bandwidth, they state that the ENG Truck Receiver Studies show harmful
interference is extremely unlikely because only a 7 dB SINR would be
needed for a 2% activity factor and a SINR below 10 dB is only possible
in a small area very close to the truck receiver and only when the
truck receiver is not elevated.
Apple, Broadcom, et al. claim that the record demonstrates that VLP
devices will not pose a significant interference risk to the link
between mobile transmitters and ENG truck receivers. To support this
claim, they refer to a set of related technical studies submitted by
Broadcom and Apple, Broadcom, et al. (collectively, ``ENG Truck
Receiver Studies''). The ENG Truck Receiver Studies use a link budget
methodology to calculate the SINR for an ENG camera transmitting at a
fixed location 94 meters from an ENG truck receiver receiving
interference from a single VLP device. The ENG Truck Receiver Studies
present plots of the variation of SINR with VLP device location within
a 94-meter radius of the ENG truck receiver for truck antenna heights
of 1.5, 2.5, 5, 10, and 15 meters. The ENG Truck Receiver Studies
assume that a portable ENG camera transmits with either 20 dBm or 23
dBm of power from a fixed location 94 meters away from the ENG truck
receiver and that the ENG truck receiver uses a 10 megahertz bandwidth,
has a 4 dB noise figure, and uses the ITU-R F.1336-4 antenna pattern
used in the Alion Study. The ENG Truck Receiver Studies use a free
space propagation model, assume that the VLP device transmits at -5
dBm/MHz, 4 dB of body loss, a power reduction of 3 dB from transmit
power control, an attenuation of 5 dB from the mismatch between the VLP
device's antenna pattern and the ENG receiver, and a 3 dB loss from
polarization mismatch between the VLP device antenna and truck
receiver. Apple, Broadcom, et al. claim that the ENG Truck Receiver
Studies show that a SINR below 1 dB only occurs when the VLP device is
operating within a few meters of the ENG truck receiver and the ENG
truck receiver antenna is located at the same height as the VLP device.
Apple, Broadcom, et al. view such a scenario as unlikely because the
receive antenna would likely be located on top of the truck or on a
telescoping mast, and the VLP device would operate so close to the
truck receiver that it could easily be observed and controlled. They
claim that ``in every realistic scenario'' the SINR will be above 8 dB.
They also point out that for antenna heights above 2.5 meters, the SINR
is greater than 10 dB at all locations. According to Apple, Broadcom,
et al., the results of the ENG Truck Receiver Studies are conservative
because 94 meters is an unusually long distance for ENG transmissions,
the ENG receiver would be elevated on a mast especially where the ENG
transmitter is located so far from the receiver, and ENG transmitters
commonly use an antenna with 3 dB of gain to transmit at 23 dBm instead
of 20 dBm. Apple, Broadcom, et al. contend that if the ENG receiver is
elevated to 5 meters, the SINR would be at least 15 dB for all
locations at least one meter from the truck.
Apple, Broadcom, et al. also suggest that the Commission adopt a
requirement that VLP devices operating in the U-NII-6 and U-NII-8 bands
be required to employ a contention-based
[[Page 11380]]
protocol as is required for the U-NII-5 and U-NII-7 bands. They point
out that the Commission previously acknowledged that the contention-
based protocol will protect incumbents by `` `avoid[ing] co-frequency
interference with other services sharing the band.' '' According to
Information Technology Industry Council, a VLP device that is near an
ENG truck receiver will also be close enough to an ENG camera
transmitter for the contention-based protocol to detect the signal and
select an alternative channel.
NAB criticizes Broadcom for assuming both the VLP devices and ENG
truck receiver are located at fixed locations with the ENG transmitter
always 94 meters away from the truck receiver. According to NAB the
purpose of using a radio link for ENG is to allow the camera
transmitter to move in real time and a Monte Carlo simulation should
consider a variety of possible scenarios. NAB also faults the ENG Truck
Receiver Studies for assuming static line-of-sight conditions, claiming
that the probability that the signals from both the ENG camera and the
VLP device will be simultaneously faded is situation-dependent and that
fades can be greater than 10 dB. NAB characterizes the 5 dB VLP/ENG
antenna mismatch and 3 dB body loss used by Broadcom as ``unexplained
and unjustified'' and claims that Apple, Broadcom, et al.'s
measurements allow for less body loss 20 percent of the time. NAB
claims that it was improper for Broadcom to include body loss, antenna
mismatch, and polarization loss for the link between the VLP device and
ENG truck receiver but not include these losses for the link between
the ENG camera and ENG truck receiver.
NAB also criticizes Broadcom's use of SINR instead of a -6 dB I/N
as has been used by the Commission. NAB explains that SINR may be
appropriate for static conditions where the signal paths are well
characterized and the systems well engineered, but both ENG and VLP
operations are variable in time and location, which indicates the
appropriate protection criteria is one that preserves the incumbent's
noise floor. Regarding use of a 1 dB SINR threshold as an interference
threshold, NAB states that Apple, Broadcom, et al. neither provide the
assumed ENG link parameters (modulation type, error correction code,
bandwidth, etc.), nor describe the bandwidth of the Wi-Fi interference.
NAB believes that the 1 dB SINR threshold employed by Apple, Broadcom,
et al. is not realistic based on bench measurements and decades of ENG
field experience by broadcasters. NAB points to bench and field tests
conducted by the Department of Defense and its contractors for the 2
GHz band that demonstrate a SINR threshold of 11.3 dB is needed to
avoid harmful interference from a co-channel interferer with a 3.2
megahertz bandwidth. NAB suggest that because 6 GHz and 2 GHz ENG
systems use identical modulation, coding, and bandwidth, this result is
applicable to the 6 GHz band and that wider bandwidth Wi-Fi signals
would have more interference potential. NAB also claims that these
measurements indicate the duty cycle of the interfering signal has
little effect because once a link is broken it requires a significant
interference-free interval to reestablish.
According to NAB, for Apple, Broadcom, et al.'s claim that VLP
devices will not pose a significant harmful interference risk to be
viable, ``the following confluence of circumstances must hold as well:
an atypically low height of the ENG receiving antenna; 4 dB of
continuous body loss; antenna pattern and polarization mismatches of 5
dB and 3 dB; operation with continuous transmit power reduction; and
static free-space conditions for both the ENG transmitter and VLP
devices.'' NAB contends that for all of these conditions to be
simultaneously true, a series of providential conditions would have to
occur. NAB also points out that Broadcom's claims that VLP devices
causing interference are likely to leave the area quickly ignore the
fact that newsworthy events frequently transpire in proximity to
crowds, meaning that ENG receivers can easily receive harmful
interference from nearby VLP devices. Because VLP devices are not
required to operate through an access point, there would not be any way
to shut down operations if interference were to occur during breaking
news event. NAB also explains that assertions that news gathering
operations are opportunistic with respect to channel selection are
incorrect and irrelevant because television stations in most markets
have defined channel plans and VLP device operation is also
opportunistic. The Society of Broadcast Engineers (SBE) states that the
studies proffered by VLP supporters are flawed as demonstrated by NAB,
in that they do not account for the full range of mobile BAS operations
and rest on mere assumptions. SBE also points to comments of the
Electric Power Research Institute (EPRI) which claim that real-world
testing has shown results differing from those predicted by Monte Carlo
simulations provided by VLP proponents and call for the models and
inputs of the studies to be made public.
NAB claims that an ENG truck receiver with an antenna height of 15
meters would receive a signal from a VLP device located 100 meters
distant that exceeds the -6 dB I/N criterion established by the
Commission by more than 34 dB. For this ENG truck receiver and VLP
device, NAB calculates that the desired-to-undesired (D/U) ratio would
be 12 dB under static conditions for a signal from a camera transmitter
located 4 meters from the truck receiver. According to NAB, this would
leave the ENG receiver only 0.7 dB from failure under static conditions
based on measurements showing a D/U ratio of 11.3 dB is required to
achieve zero uncorrected errors. NAB claims that this 0.7 dB margin for
a typical link configuration is unacceptably low because some
configurations will fall short of the median value and the link will
not close. NAB notes that in addition both transmitters are likely to
be in motion, resulting in statistical fading due to multipath effects,
which increase the likelihood of harmful interference.
Apple, Broadcom, et al. respond to NAB that there is no record
support for NAB's claim that an 11.3 dB D/U ratio is required for
error-free ENG operation, noting that NAB's citation is to an NAB
conference related to the 2 GHz band. Apple, Broadcom, et al. fault NAB
for failing to address the Broadcom measurement data that directly
contradicts this claim and that the Commission relied on in the 6 GHz
First Order. Apple, Broadcom, et al. claim that the ENG Truck Receiver
Studies employ a more conservative methodology than a Monte Carlo
approach because they used an ENG transmitter 94 meters from the
receiver while a Monte Carlo approach would have included a large
number of shorter distances. Apple, Broadcom, et al. note that NAB
raised the same objection regarding fading about a 2020 ENG study by
Broadcom that it raises about the ENG Truck Receiver Studies and that
the Commission rejected this contention in the 6 GHz First Order.
Apple, Broadcom, et al. also note that the assumption of 5 dB from the
mismatch between the VLP device's antenna pattern and the ENG receiver
and 4 dB for body loss that NAB criticizes are consistent with
assumptions upon which the Commission has previously relied.
Discussion. The Commission concludes that VLP devices can operate
without creating a significant risk of harmful interference to
communication links between portable ENG transmitters and ENG truck
receivers. The Commission bases this conclusion on
[[Page 11381]]
many factors, including the large power differential between portable
ENG transmitters and VLP devices, the requirement that VLP devices
employ a contention-based protocol, and the low probability that a VLP
device will overlap the ENG signal in frequency because of the large
amount of spectrum available for VLP operations. The results of the ENG
Truck Receiver Studies provide additional support for the Commission's
conclusion.
The consequences of the large power differential between ENG
portable transmitters and VLP devices is illustrated by examining in
detail the example provided by NAB of an ENG truck receiver with a 15
foot high antenna receiving signals from a VLP device located 100
meters away and an ENG portable camera transmitter located 4 meters
away. This situation represents one of the worst potential interference
cases because the VLP device is in the main beam of the ENG truck
receiver antenna while the ENG portable camera transmitter is far below
the antenna's main beam. According to the antenna pattern for an ENG
truck receiver used in a Alion Study previously submitted by NAB, the
antenna gain toward the VLP device would be 10.1 dB while the gain
would be only -8.9 dB toward the ENG portable camera signal, assuming
both transmitters are at a 1.5 meter height. This 19 dB difference in
antenna gain is greater than the difference in propagation loss of 17.1
dB between the two locations using a free space path loss model, which
illustrates that moving the VLP device closer to the truck receiver
would not result in the VLP device's interference potential being
appreciably worse.
In providing this example, NAB has considered only the antenna gain
and propagation loss in calculating the received power from these two
transmitters. In the 6 GHz First Order, when the Commission examined a
set of link budget examples provided by AT&T, it treated statistical
quantities such as polarization loss and antenna discrimination using
median or average values. As was done in the 6 GHz First Order, the
Commission believes that for a static link budget analysis it is
appropriate to treat such statistical quantities using median values
when calculating signal levels for NAB's example case. Using mean
values for these parameters, the Commission evaluates the received
signal power from the VLP device--operating at -5 dBm/MHz EIRP PSD and
14 dBM EIRP--at the ENG truck receiver to be -88.8 dBm. For the ENG
camera transmitter, NAB used 20 dBm as the transmit power. As Apple,
Broadcom, et al. point out, ENG camera transmitters commonly use
antennas with 3 dB of gain which would increase the transmit EIRP to 23
dBm. This results in -57.6 dBm received signal power at the ENG truck
receiver. The resulting D/U ratio is 31.2 dB, which greatly exceeds the
11.3 dB D/U ratio that NAB states is necessary to avoid harmful
interference. Even if the ENG portable camera transmits with only 20
dBm of power, the resulting 28.2 dB D/U ratio would greatly exceed the
11.3 dB D/U ratio. Regarding NAB's concern that fading is likely to
occur from the motion of the devices thereby increasing the
interference likelihood, given that both the ENG transmitter and VLP
device are likely to be stationary or possibly moving slowly and that
the distances between transmitters and the receiver are less than 100
meters, the Commission expects that any fading that occurs would be
mild and less than 10 dB in magnitude. These large D/U ratios indicate
that even with that level of fading the D/U ratio would remain above
11.3 dB. This illustrates that VLP devices operating at the power level
that the Commission is permitting under its rules are unlikely to cause
harmful interference to this type of ENG operation. In addition, for
this particular example, the signal from the VLP device is likely to
experience more clutter loss than the signal from the ENG transmitter
due to the greater distance, which suggests that the D/U ratio would be
even greater.
The fact that the Commission is requiring the VLP devices to employ
a contention-based protocol also lessens the risk that harmful
interference will occur to ENG operations. For the scenarios discussed
in both NAB's examples and the ENG Truck Receiver Studies, the portable
ENG transmitter is likely to be within a relatively close distance to
the truck receivers--i.e., 100 meters or less. VLP devices that present
a harmful interference risk are also likely to be within such a
distance of the ENG truck receiver. Consequently, the VLP devices and
portable ENG transmitters will operate in close proximity to each
other. In such situations, the VLP device should be able to detect when
a portable ENG transmitter is operating nearby on the same channel.
Because the portable ENG transmitter operates continuously when sending
a video signal, the Commission would expect that the contention-based
protocol used by the VLP device will cause it to vacate the channel
used by the portable ENG transmitter and thereby further lessen the
potential for harmful interference to occur.
Because there is 1,200 megahertz of 6 GHz band spectrum available
for VLP device operation under the rules adopted in the Third Report
and Order, it is unlikely that a VLP device will transmit co-channel
with a portable ENG camera transmitter. This provides additional
protection against harmful interference occurring. For a VLP device
using a 20 megahertz bandwidth, there is a 1.7% chance of channel
overlap with an ENG transmitter operating in a 10 megahertz bandwidth.
For VLP devices using a 160 megahertz bandwidth, the likelihood of
channel overlap would be 11.8%.
The Commission is basing its conclusion that there is an
insignificant risk of harmful interference occurring to ENG truck
receivers from VLP operations on the factors discussed above: the power
differential between VLP devices and portable ENG transmitters, the use
of a contention-based protocol by VLP devices, and the large amount of
spectrum available for VLP operations in the 6 GHz band. In addition to
these factors, the Commission also recognizes that the ENG Truck
Receiver Studies provide additional evidence to support this
conclusion. Despite NAB and SBE's contentions, the Commission believes
that the assumptions used in the ENG Truck Receiver Studies are
appropriate. The 4 dB for body loss, 3 dB power reduction from transmit
power control, 5 dB attenuation from the mismatch between the VLP
device's antenna pattern and the ENG truck receiver, and 3 dB loss from
polarization mismatch between the VLP device antenna and the ENG truck
receiver are consistent with the assumptions that the Commission
concluded were appropriate in the 6 GHz First Order and/or the 6 GHz
Second Order. The Commission also believes that Broadcom was correct
not to include these losses for the ENG camera to ENG truck receiver
link. As shown in the pictures submitted by NAB, the portable ENG
cameras use an external antenna that is not body worn and is located on
the back of the camera that is at least half a foot from the operator's
body. Because this antenna is located several wavelengths away from
body, body loss is expected to be insignificant. As the vertical
orientation of the antenna does not change as the camera operator
moves, there is unlikely to be polarization loss. Antenna pattern
mismatch is not a significant factor for large external antennas that
have omni-directional patterns such as the camera antennas. The ENG
Truck Receiver
[[Page 11382]]
Studies assume a receiver bandwidth, noise figure, and antenna pattern
that were taken from the Alion Study previously submitted by NAB, which
included an interference analysis for an ENG portable camera
transmitting to an ENG truck receiver. In addition, contrary to NAB's
contention, Broadcom does indicate the ENG camera's modulation, coding
rates, and signal bandwidths used in its SINR measurement study. While
Broadcom does not specify the unlicensed device signal bandwidth when
conducting these measurements, the Commission presumes that the
unlicensed device's signal fully overlaps the 8- or 10-megahertz ENG
signals examined based on the 20-megahertz minimum Wi-Fi bandwidth.
In examining the ENG Truck Receiver Studies, the Commission
appreciates that a 94-meter distance between the ENG portable camera
transmitter and ENG truck receiver is at the outer range of what is
likely to occur in practice. Given this large distance between the ENG
portable camera transmitter and the ENG truck receiver, the Commission
would expect that the ENG truck receiver would use an elevated
antenna--at least 5 meters in height--in order to increase the
available margin by elevating the signal path over any obstacles. At
such a height, the ENG Truck Receiver Studies indicate that the SINR
would be greater than 11 dB for VLP devices located anywhere within 94
meters of the ENG truck receiver when the camera is transmitting at 20
dBm and greater than 14 dB if the camera transmits at 23 dBm. When the
ENG truck is being used to relay video signals to a central receive
site, it would likely use a 15-meter antenna height to rise above any
ground clutter and to achieve a line-of-sight link to the ENG central
receive site, which would result in a SINR of over 23 dB. Even if a
2.5-meter antenna height were used, as would be the case for a receiver
on the roof of the truck, the area where a VLP device would result in a
SINR that is lower than 10 dB is small and the SINR remains above 8 dB
everywhere for an ENG camera transmitting at 20 dBm.
The Commission cannot endorse use of an SINR of 1 dB as an
indication of whether there is an insignificant risk of harmful
interference occurring when examining the results of the ENG Truck
Receiver Studies, as suggested by Apple, Broadcom, et al. According to
the SINR measurements submitted by Broadcom, a 1 dB SINR is needed to
ensure error-free video signals when a Wi-Fi device with a 2% activity
factor when an 10 megahertz bandwidth video signal is used. While this
appears to be a valid result for a static channel, the Commission
agrees with NAB that fading may affect the signals received from the
ENG transmitter and VLP device. No information submitted on the record
addresses the extent of fading that may occur other than NAB's
unsupported contention that such fading may be greater than 10 dB.
Given that the portable ENG camera transmitter and body worn VLP
devices are likely to be stationary or moving slowly and that the
distances between transmitters and the receiver are less than 100
meters, the Commission expects that any fading that occurs would be
mild and less than 10 dB in magnitude. Even with this level of fading
the ENG Truck Receiver Studies supports the Commission's conclusion
that there is an insignificant risk that harmful interference will
occur to the ENG truck receivers. The ENG Truck Receiver Studies
indicate that for an ENG truck receiver antenna elevation of at least 5
meters, the SINR remains above 11 dB when the ENG transmitter is
transmitting at 20 dBm and the SINR is above 14 dB when the ENG
transmitter is transmitting at 23 dBm. The Commission notes that an 11
dB SINR is only slightly lower than the 11.3 dB SINR at which NAB
claims bench and field tests demonstrate to be the median threshold for
no harmful interference. The SINR increases to at least 23 dB when the
ENG truck receiver antenna is raised to 15 meters as would often occur
for relaying a video signal to an ENG central receive site. While the
ENG Truck Receiver Studies indicate the SINR can be as low as 8 dB if
the ENG truck receiver height is only 2.5 meters, the Commission notes
that NAB states that with robust modulation and coding the required
SINR can be reduced to 7.3 dB. In addition, Apple, Broadcom, et al.
show that the SINR will exceed 8 dB in every scenario examined and that
SINRs of less than 11 dB are quite rare, providing an additional basis
for the Commission's conclusion that the risk of harmful interference
to mobile receivers is insignificant.
The Commission does not believe that the ENG Truck Receiver
Studies' examination of the SINR produced by VLP devices instead of I/N
is improper, as NAB suggests. In the 6 GHz First Order, the Commission
agreed with the technical study findings provided by CableLabs and
Apple, Broadcom, et al. that examined the potential for interference
from 6 GHz low-power indoor devices to ENG truck receivers, which used
SINR as a measure of interference potential. It also adopted a -6 dB I/
N ratio for use by the automated frequency coordination (AFC) systems
that manage spectrum access by 6 GHz standard power access points. The
Commission made the decision to use I/N for this purpose based on
implementation simplicity and because it was used by most commenters in
their analyses. In making this decision, the Commission clearly stated
that it was not ``making a determination that any signal received with
an I/N greater than -6 dB would constitute harmful interference.'' The
Commission did not prohibit (or imply that it was prohibiting) the use
of other signal quality measurements besides I/N as an indication as to
whether harmful interference may occur. In examining a study that uses
SINR, the Commission is not implying that any SINR below a particular
level constitutes harmful interference.
The Commission agrees with NAB that a Monte Carlo simulation that
considers a wide variety of situations would have been more informative
than the approach employed by the ENG Truck Receiver Studies. The
Commission acknowledges the limitations of the ENG Truck Receiver
Studies in only considering one location for the ENG camera transmitter
rather than examining more scenarios as could have been done in a Monte
Carlo simulation. Despite this limitation, the Commission concludes the
ENG Truck Receiver Studies provide additional support for concluding
that there is an insignificant harmful interference risk to ENG
receivers from VLP devices.
The Commission disagrees with SBE that the evidence to support VLP
operations is flawed because the various studies submitted for the
record do not account for the full range of mobile operations. As
explained above, the Commission is limiting its discussion to three use
cases--ENG central receive sites, ENG truck receivers, and low-power
short range devices--consistent with the 6 GHz Second FNPRM and the
approach followed for low-power devices in the 6 GHz First Order. As
neither SBE nor any other commenters have suggested other use cases
beyond these three cases, the Commission believes the approach the
Commission is following is reasonable. The Commission also disagrees
with SBE that the technical studies from Apple, Broadcom, et al. are
flawed because EPRI claims real-world test have shown differing results
from previous Monte Carlo simulations. The measurement studies that
EPRI cites all claim that interference is occurring from unlicensed
devices at particular fixed locations because the I/N ratio is greater
[[Page 11383]]
than -6 dB. Because Monte Carlo simulations are designed to examine the
likelihood of interference occurring in general and the simulations
have indicated that it is not impossible for an I/N over -6 dB to
occur, the fact that there may exist locations where the I/N exceeds -6
dB does mean that the results differ from the Monte Carlo simulations.
In addition, the Commission has not indicated that the occurrence of an
I/N of greater the -6 dB indicates that harmful interference is
occurring. The Commission also rejects EPRI's suggestion that the
models and inputs of the Monte Carlo simulations be made publicly
available for the same reasons the Commission rejected a similar
request in the 6 GHz Second Order. The Commission believes that Apple,
Broadcom, et al. and Broadcom have provided sufficient information for
knowledgeable engineers to understand the algorithms and models used in
the technical studies they have submitted and find it noteworthy that
no opponent of VLP expansion to U-NII-6 and U-NII-8 have conducted
their own similar technical studies.
In reaching its conclusion that VLP devices will not present a
significant risk of causing harmful interference to ENG truck
receivers, the Commission is not relying on the opportunistic nature of
ENG operations or on the assumption that VLP devices causing
interference are likely to leave the areas quickly. Mobile ENG
operations by broadcasters are conducted on a primary basis and
licensees have the right to operate on any channel permitted by their
license and are not expected to need to adjust their operating
frequency to avoid VLP devices. The Commission also does not find that
NAB's concern that there would be no way to shut down VLP devices that
cause interference during a breaking news event provides justification
for prohibiting VLP devices in the U-NII-6 and U-NII-8 bands because
the record supports its conclusion that the risk of such harmful
interference occurring would be insignificant. Because of the
difference in power levels between the ENG operations and VLP devices,
the use of a contention-based protocol by VLP devices, and the large
amount of spectrum available for VLP operations, the Commission expects
there to be an insignificant risk that harmful interference will occur
to ENG truck receivers. This conclusion is further supported by the ENG
Truck Receiver Studies.
Low-Power Short Range Mobile Devices
No commenters provided technical studies or described specific use
cases for low-power short range mobile devices. Low-power short range
mobile devices include portable cameras and microphones as well as Low-
power Auxiliary Stations, which 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. While the Commission refers to these devices
as low-power short range mobile devices, they operate at significantly
higher power than VLP devices--portable ENG cameras typically operate
at 20 dBm and Low-power Auxiliary Stations may operate at up 30 dBm.
The 6 GHz Second FNPRM suggested that these low-power short range
mobile devices be protected by a combination of a required contention-
based protocol and the low probability of a VLP device operating on the
same channel in a nearby location. The Commission concludes that these
measures will adequately protect low-power short range mobile devices
from harmful interference from VLP devices.
The 6 GHz First Order discussed a simulation submitted by Apple,
Broadcom, et al. that simulated ENG equipment operating indoors within
the U.S. House of Representatives chamber, a scenario which had been
explored in the Alion Study submitted by NAB. To confirm that the
energy sensing employed by the contention-based protocol in the 802.11
specification could be used to mitigate interference to indoor ENG
receivers, the simulation calculated the received power level from ENG
transmitters at 20 unlicensed access point locations operating within
the U.S. House of Representatives chamber. The results of this
simulation demonstrate that, even at the lowest ENG transmit power
level, all unlicensed access points would detect the ENG signal at
greater than the -62 dBm threshold used in the 802.11 specification and
therefore not transmit co-channel with the ENG transmitters. While this
simulation was limited to low-power ENG cameras and associated
receivers, it should equally apply to other low-power short range
mobile devices that operate with similar power levels and at similar
distances. This simulation illustrates that unlicensed VLP devices
using such a contention-based protocol have the capability to sense the
energy from nearby low-power mobile devices and avoid using the same
channel. In addition, for the same reasons as discussed above regarding
ENG truck receivers, the 1200 megahertz of 6 GHz band spectrum
available for VLP device operation makes it unlikely that even absent a
contention-based protocol, these devices would transmit co-channel with
low-power short range mobile devices.
Reservation of Spectrum for ENG
The Commission notes that NAB requests that the Commission ``adopt
a 55 MHz carve-out at the top of the U-NII-8 band at which no VLP
operations are permitted, at least until there is significant
experience to determine such a carve-out is unnecessary.'' NAB has made
similar requests previously in this proceeding, and in both instances
the Commission chose not to adopt NAB's suggestion. In this case, NAB
repeats prior concerns without providing any new information that
addresses any changes in operational parameters. As the Commission has
thoroughly addressed interference considerations related to VLP
operations in the U-NII-6 and U-NII-8 bands herein and found that such
operations will have an insignificant potential for causing harmful
interference to ENG operations, it declines to adopt NAB's suggestion.
Protecting Fixed Services
The operational and technical characteristics of the limited number
of fixed microwave links in the U-NII-6 and U-NII-8 bands are
consistent with those in the U-NII-5 and U-NII-7 bands. Because the
Commission is adopting identical technical rules for VLP operation in
the U-NII-6 and U-NII-8 bands as apply in U-NII-5 and U-NII-7 bands,
the Commission's conclusion in the 6 GHz Second Order that VLP
operations will not present a significant risk of harmful interference
to fixed microwave links applies equally to the U-NII-6 and U-NII-7
bands.
Apple, Broadcom, et al. and the IEEE 802 LAN/MAN Standards
Committee support this contention, suggesting that the previously
conducted studies demonstrate that there will be no harmful
interference to incumbent fixed microwave services in the U-NII-6 and
U-NII-8 bands. AT&T raises concerns that the simulation studies the
Commission previously relied upon remain unfiled and untested and
contends it is poor public policy to rely on studies that have not been
filed for public review. The Fixed Wireless Communications Coalition
(FWCC) states that the record was insufficient to act on the proposals
prior to the 6 GHz Second FNPRM and remains insufficient to support
Commission action because the comments ``were either non-substantive or
rehashed information previously submitted [in] the record.'' Several
microwave licensees and their representatives urge
[[Page 11384]]
the Commission to gain real-world experience or require testing with
VLP devices before further liberalizing the rules. The American
Petroleum Institute (API) raises several specific concerns regarding
the technical studies that the Commission relied upon in its decision
to permit VLP in the U-NII-5 and U-NII-7 bands. API claims that for the
Houston area microwave link simulation (Houston Simulation) submitted
by Apple, using an antenna based on the Commission's rules instead of
the 44 dBi gain antenna with the ITU-R F.1245 pattern relied upon by
Apple, would have resulted in more predicted interference. API also
criticizes the Houston Simulation's use of 1.3 dB cable loss (i.e.,
feeder loss) for microwave systems, claiming that most modern microwave
systems utilize receivers with the radio directly connected to the
antenna that may have less than 0.5 of coupling loss. Regarding the
Commission's discussion of a link budget analysis submitted by Nokia,
API suggest that the Commission should not have included a 2 dB feeder
loss and that what API refers to as ``antenna polarization mismatch''
should have been 1.5 dB instead of 5 dB.
In responding to AT&T's previous request that the code for the
simulation studies be publicly disclosed, the Commission in the 6 GHz
Second Order explained that both Apple, Broadcom, et al. and Apple
provided sufficient information regarding their simulations. The
Commission sees no reason to reconsider this finding or the
Commission's reliance on these simulations in concluding that VLP
devices will not result in a significant risk of harmful interference
to fixed microwave receivers. The Commission also does not agree with
FWCC's general contention about the sufficiency of the record to
support its expansion of VLP operations to the U-NII-6 and U-NII-8
bands. Given that the VLP operations the Commission is now authorizing
in the U-NII-6 and U-NII-8 bands are identical to what the Commission
currently permits in the adjacent much larger U-NII-5 and U-NII-7
bands, the Commission sees no reason to pause its rulemaking for some
unspecified time to gain experience with VLP devices as suggested by
some of the microwave licensees.
Regarding API's concerns, the 6 GHz Second Order explained that the
Houston Simulation's use of the ITU-R F.1245 antenna pattern with a 44
dBi gain was appropriate because it represents an ``average'' antenna,
which would provide a reasonable estimate of microwave link
interference performance. The goal of a Monte Carlo simulation is to
obtain overall statistics on the potential for harmful interference to
occur to all microwave links. Hence, the Commission disagrees with
API's contention that a pattern based strictly on what is permitted by
its rules would be more appropriate, as this would likely result in a
worst-case overprediction of harmful interference occurring rather than
overall interference statistics. Regarding the Houston Simulation's 1.3
dB feeder loss, AT&T previously raised the same concern that some
microwave radios are mounted directly to the antenna and have no feeder
loss. The 6 GHz Second Order explained that using 1.3 dB feeder loss
was a reasonable approach as the simulation is designed to model the
interference potential in general rather than explore the interference
risk for a particular microwave receiver.
The Commission also does not agree with API's concerns regarding
the Nokia link budget analysis. Contrary to API's contention, the 5 dB
loss the Commission applied was for ``RLAN/FS antenna pattern mismatch
between unlicensed devices and microwave receivers'' rather than for a
polarization mismatch. This 5 dB value was used by the Commission in
link budget analyses in the 6 GHz First Order for analyzing potential
interference from low-power indoor devices to microwave receivers and
is based on the antenna patterns of typical indoor enterprise and
consumer access points. In those analyses, the Commission applied a
separate attenuation for polarization loss. The Commission also used a
2 dB feeder loss for the link budget analysis in the 6 GHz First Order.
The 6 GHz Second Order explained that because the Nokia analysis is a
link budget that assumes the same type of microwave antennas and that
the VLP devices likely have similar antenna patterns to the low-power
indoor devices, these assumptions are appropriate for examining the
Nokia analysis. The Commission also notes that even after the
Commission applied these adjustments for antenna pattern mismatch and
feeder loss, Nokia's suggested VLP power would be -11 dBm/MHz EIRP,
which is significantly lower than the -5 dBm/MHz EIRP limit the
Commission adopted for VLP devices. As the Commission explained, a
Monte Carlo analysis rather than a static link budget analysis is a
more realistic indication of the potential for VLP devices to cause
harmful interference. Hence, even if the Commission had not applied the
7 dB of adjustment to the Nokia analysis, it would not have changed its
conclusion regarding the risk of harmful interference occurring to
microwave receivers from VLP devices.
Fixed-Satellite Service Uplinks
In the 6 GHz First Order, the Commission authorized standard power
devices in the U-NII-5 and U-NII-7 portions of the 6 GHz band and low-
power indoor unlicensed devices across the entire 6 GHz band. To
protect FSS uplinks that operate in all except the upper fifty
megahertz of the 6 GHz band, the Commission required outdoor standard
power access points to limit their maximum EIRP above a 30 degree
elevation angle to 21 dBm. However, the Commission determined no
restrictions were necessary for low power indoor devices because of
these device's relatively low EIRP as well as building attenuation due
to the indoor operation. Similarly, in the 6 GHz Second Order, the
Commission determined that VLP devices operating in the U-NII-5 and U-
NII-7 bands did not require any restrictions because VLP devices are
limited to no more than 14 dBm. In the 6 GHz Second FNPRM, the
Commission proposed expanding VLP access to the entire 6 GHz band but
made no specific proposal regarding protecting FSS Earth-to-space
operations.
Sirius XM urges the Commission to prohibit outdoor VLP devices in
the upper U-NII-8 band, as they may disrupt Satellite Digital Audio
Radio Service (SDARS) operations. While SDARS is not a part of the FSS,
its ground stations use a portion of the U-NII-8 band to transmit
digital audio signals to Sirius XM's geostationary satellite
constellation. Sirius XM points out that the only analysis provided by
unlicensed proponents of interference to FSS receivers was a 2018 study
conducted by RKF Engineering (2018 RKF Study) that addressed FSS, but
not SDARS. According to Sirius XM, SDARS is different than FSS because
it must deliver a reliable signal to consumer-grade antennas rather
than the large high-gain antennas used by C-band FSS operations. Sirius
XM previously criticized the assumptions used by the 2018 RKF Study and
further calls into question a number of its assumptions. Specifically,
Sirius points out that the 2018 RKF Study assumed a 2% outdoor use
factor while more recent simulations have assumed a 6% outdoor use
factor, that the Study used an estimate of 6 GHz band unlicensed
devices that is far lower than more recent estimates of connected
devices from Cisco, and that device activity factors have been trending
higher due to increased video streaming. Sirius points out that the
interference levels from VLP
[[Page 11385]]
devices would be 40 times higher than low-power indoor devices due to
the lack of building attenuation. Sirius XM also cautions that once
interference occurs to SDARS, there would not be a practical
enforcement mechanism to resolve it. Sirius contends that the risk of
harm to the valuable SDARS service outweighs the benefit of satisfying
an undemonstrated need for more spectrum for outdoor VLP device use.
Sirius XM renews its previous proposal that the Commission prescribe a
maximum aggregate increase in the uplink noise floor and prohibit the
manufacture, importation, and sale of additional unlicensed devices if
a -23 dB I/N is exceeded. It also suggests that VLP devices be required
to prioritize other parts of the 6 GHz spectrum outside of the SDARS
uplink band.
Apple, Broadcom, et al. respond that Sirius XM presents no detailed
analysis of the interference risk to its system, nor any concrete
interference protection requirements. Apple, Broadcom, et al. contend
that Sirus XM's satellites are no different from other 6 GHz FSS
operations in that they receive aggregate interference over a large
footprint and receive interference from numerous existing terrestrial
licensees and that the record demonstrates these other devices
contribute orders of magnitude more energy than unlicensed devices
will. According to Apple, Broadcom, et al., high power 6 GHz licensees
will continue to be the dominant interferers to Sirius XM's uplinks,
not VLP devices. They point to the 2018 RKF Study on the potential for
interference from standard-power devices operating at 4 Watts (36 dBm)
and claim that interference from VLP devices would be even fainter than
the -20 dB I/N predicted.
Discussion. The Commission believes that its previous conclusion
that FSS uplinks in the U-NII-5 and U-NII-7 bands will not have a
significant risk of experiencing harmful interference from VLP devices
applies equally to FSS uplinks in the U-NII-6 and U-NII-8 bands,
including to Sirius XM's SDARS system. This conclusion is based on the
fact that VLP devices, which can operate with up to 14 dBm EIRP, will
transmit with significantly less power than the 21 dBm power permitted
above 30 degrees elevation for standard power access points. Sirius
XM's SDARS operations in the U-NII-8 band have the same characteristics
as 6 GHz FSS systems. As with 6 GHz band FSS systems, its satellites
operate in geostationary orbits and have receive beams that cover the
entire United States. Its satellites potentially receive interference
from other licensed users that share the 6 GHz band just as 6 GHz FSS
uplinks. As to Sirius XM's observation that the power received from
outdoor VLP devices can be significantly higher than the power from
low-power indoor devices due to the lack of building attenuation, the
power from outdoor VLP devices would be significantly less than that of
standard power access points, which its rules permit to operate
outdoors and which the Commission previously found are unlikely to
cause harmful interference to FSS receivers.
The Commission notes that Sirius XM has not produced any technical
analysis regarding the Commission's proposal to permit U-NII-8 VLP
operations. Instead, Sirius XM refers back to its previous critique of
the 2018 RKF Study, which was available to the Commission prior to
adopting the rules for 6 GHz band standard power and low-power indoor
devices. The only new points regarding the 2018 RKF Study that Sirius
XM now raises are that more recent technical studies regarding VLP
devices filed by unlicensed proponents assume a 6% outdoor use factor
instead of 2%, that Cisco recent estimates of connected devices are
higher than the 2018 RKF Study, and that unlicensed device activity
factors will continue to increase due to video downloads. The
Commission notes that the 6% and 2% outdoor use factors to which Sirius
refers have different meanings in the 2018 RKF Study than in the more
recent VLP simulation Sirius references. The 2018 RKF Study assumed
that 2% of the ``RLANs'' are outdoors while the Apple, Broadcom, at al.
simulation of VLP use in San Francisco assumed 6% of the people were
outdoors with 25% of those people using VLP devices and only 2% of
those devices active at any given time. The two simulations also had
different foci: The 2018 RKF Study simulated radio local area networks,
including Wi-Fi access points, both indoor and outdoor across the
entire United States while the Apple, Broadcom, at al. simulation only
considered outdoor VLP use in San Francisco. Given the different
meanings of these outdoor use factors, the Commission cannot directly
compare whether the two simulations in fact represent a different level
of outdoor device use. Because of the different scope of these two
simulations, the Commission believes it was appropriate to use
different methodologies for modeling the number of outdoor devices. The
Cisco connected device data Sirius XM points to is for all internet-
connected devices in general and not for 6 GHz VLP devices in
particular. As for the contention regarding increasing device activity
factor because of growing video activity on the internet, the
Commission stated in the 6 GHz Second Order, which was adopted in 2023,
that assuming a 2% activity factor for VLP devices is reasonable for
analytical purposes and the Commission sees no reason to reconsider
this conclusion. Given the limited new technical information that has
been presented, the Commission is not convinced that it should
reconsider its conclusion as to the likelihood of interference
occurring to FSS uplinks.
Sirius's concern about the lack of any practical enforcement
mechanism if harmful interference were to occur also does not give the
Commission reason to limit VLP access to the U-NII-8 band. The
Commission is concluding, based on the currently available technical
evidence, that there is an insignificant risk that harmful interference
will occur to 6 GHz FSS systems and SDARS systems and thus there is no
basis to prevent the introduction of an exciting new service to the
public. As the demand for spectrum continues to grow, the Commission
believes that it is in the public interest to continue to find ways to
more intensively use the valuable spectrum resource, so long as the
Commission also concludes that the evidence presented in the record
shows the likelihood for harmful interference to remain insignificant.
Because the Commission has concluded that the likelihood of harmful
interference occurring to Sirius XM's system from VLP devices is
insignificant, it sees no reason to adopt an aggregate interference
threshold as Sirius XM suggests. The Commission also does not find it
appropriate to require VLP devices to prioritize operations in portions
of the 6 GHz band outside of the SDARS uplink spectrum because the
record does not support that Sirius XM will experience a harmful
interference problem from VLP device operations.
Fixed-Satellite Service Downlinks
Portions of the U-NII-7 and U-NII-8 bands are allocated for FSS
space-to-Earth (downlink) operations. However, no such earth stations
are currently licensed in the U-NII-7 band. The U-NII-8 space-to-Earth
allocation is limited to use by non-geostationary Mobile-Satellite
Service feeder links. Globalstar operates earth station receive sites
in the U-NII-8 band at Clifton, TX, Naalehu, HI, Wasilla, AK, Reno, NV,
Sebring, FL, and Barrio of Las Palmas, Cabo Rojo, PR.
In the 6 GHz Second FNPRM, the Commission sought comment on
[[Page 11386]]
whether any restrictions on VLP devices are necessary to protect space-
to-Earth stations. The Commission recognized that VLP devices operate
at significantly lower power spectral density levels than the geofenced
VLP devices it also proposed to permit in the 6 GHz Second FNPRM;
therefore, it sought comment on how this difference impacts the
analysis of potential harmful interference. Globalstar, the only
stakeholder in the U-NII-8 band for FSS downlink transmission,
expresses concern that a new class of higher-power, geofenced VLP
devices could cause harmful interference and suggests that the
geofencing system protect their earth stations. However, Globalstar
does not address VLP operations of the type previously authorized in
the U-NII-5 and U-NII-7 bands.
In the 6 GHz First Order, the Commission concluded that the low
probability of harmful interference to FSS space-to-Earth stations from
low-power indoor devices in the U-NII-8 band was due to the indoor
restriction and a transmit EIRP below 30 dBm. While a majority of VLP
use cases are expected to be indoors, there will undoubtably be
scenarios in which VLP operations occur outdoors. In these cases, VLP
transmissions will still be attenuated by transmit power control (TPC)
and body loss. Additionally, at 1.5 meters at which most VLP devices
will be operated there will be significant clutter loss. These losses
will bring the effective EIRP below that of a low-power access points
effective EIRP. The Commission also notes that Globalstar has raised no
interference concerns regarding VLP operation in U-NII-8 at the current
VLP power levels. Therefore, the Commission concludes that no
restrictions on VLP devices are necessary to protect FSS space-to-Earth
operations.
Protecting Passive Services
The Committee on Radio Frequencies (CORF) expresses concerns about
potential interference from VLP devices to the radio astronomy service
and to the Earth Exploration Satellite Service (EESS) in the U-NII-6,
U-NII-7, and U-NII-8 bands. 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. Remote sensing using the EESS,
which CORF states is critical to weather prediction and the study of
climate change and of the Earth in general, operates in the 6.425-7.250
GHz band, which includes all of the U-NII-6, U-NII-7, and U-NII-8
bands. CORF argues that the methodology the Commission used in the 6
GHz Second Order to calculate VLP power limits in the U-NII-7 band by
extrapolating the low-power indoor power limits was not appropriate in
that the Commission failed to properly take into account differences
between the two types of devices, including power levels and building
entry loss. CORF requests that certain frequencies around the 6.65-
6.6752 GHz band be made unavailable to VLP devices in areas close to
radio astronomy sites, but suggests that these frequencies could be
made available in areas where the spectrum is congested but are
sufficiently removed from radio astronomy sites to avoid causing
interference.
With regard to the EESS in the U-NII-6, U-NII-7, and U-NII-8 bands,
CORF argues that a 14 dBm EIRP VLP device would exceed the ITU-R
RS.2017 -166 dBW interference threshold in a 200 MHz bandwidth. It
states that a single 14 dBm EIRP VLP device within a receiver's antenna
beam and passband could result in a signal that exceeds the ITU-R
RS.2017 threshold by as much as 33 dB. CORF further states that VLP
devices in the U-NII-5 band would have a negligible effect on sensing
operations in the bands where the EESS operates. As a result, CORF
states that geofencing could be used with devices programmed to avoid
the U-NII-6, U-NII-7, and U-NII-8 bands in oceanic zones, including in
coastal waters, and non-geofenced usage could be restricted to the U-
NII-5 band only.
Discussion. The Commission declines to restrict the frequencies
that may be used by VLP devices in the U-NII-7 band to protect radio
astronomy operations. That request is outside the scope of this Order,
which addresses VLP operations in only the U-NII-6 and U-NII-8 bands.
However, the Commission notes that in the 6 GHz Second Order the
Commission already considered and rejected CORF's request to prohibit
use of certain frequencies by VLP devices to protect radio astronomy
operations, stating that the interference potential for VLP devices in
the U-NII-7 band is even lower than for low-power indoor devices that
were already permitted to operate at higher power levels than those
adopted for VLP devices. The Commission continues to believe that VLP
devices in the U-NII-7 band are unlikely to interfere with radio
astronomy operations, noting that CORF's analysis, in which it
questioned the validity of extrapolating the low power indoor device
power limit to determine the appropriate VLP device power limit,
suggests a greater value for building entry loss (30 dB) than the
Commission previously found to be appropriate (20.5 dB). Additionally,
CORF failed to consider mitigating factors that reduce the potential
for interference, including, 3 dB for the use of TPC, 4 dB for body
loss, and 2% (17 dB) activity factor correction.
The Commission finds that it can permit VLP devices to operate in
the U-NII-6 and U-NII-8 bands while protecting the EESS. In the 6 GHz
Second Order, the Commission permitted VLP devices to operate in the U-
NII-7 band where the EESS also operates, subject to a prohibition on
their use on oil platforms to protect ocean temperature sensing
activities. The power levels the Commission are permitting for VLP
devices in the U-NII-6 and U-NII-8 bands are the same as those the
Commission permits for VLP devices in the U-NII-7 band, and as
discussed below, the Commission is maintaining the prohibition on
operation on oil platforms. Consequently, EESS operations in the U-NII-
6 and U-NII-8 bands will be protected to the same extent that they are
in the U-NII-7 band.
CORF's analysis of potential interference in the U-NII-6 and U-NII-
8 bands overstates VLP device interference potential to the EESS. In
particular, CORF's analysis fails to consider certain mitigating
factors that the Commission previously found to be appropriate. When
using the Commission's previously assumed factors of 5 dB for antenna
pattern mismatch, 3 dB for antenna polarization loss, 20.5 dB for
building entry loss, 3 dB for the use of TPC, and 4 dB for body loss,
the Commission calculates a 4.2 dB protection margin. It should be
noted that this calculation does not take into account clutter loss
that can exist. Furthermore, given that EESS observation times are in
the order of milliseconds while Wi-Fi transmissions are generally in
the order of microseconds, the Commission believes that using the
average power instead of peak power is appropriate. With a conservative
2% activity factor assumption (a 17 dB reduction), the protection
margin evaluates to 21.2 dB.
Given the limited footprint of EESS satellites, the significant
protection margin that exists, and that large numbers of VLP devices
generally are not transmitting simultaneously on boats in an area, the
Commission believes that continuing to allow VLP devices to operate on
boats in the ocean will not result in any significant risk to EESS
operations. For these same reasons, the Commission does not see a need
to impose restrictions on VLP devices over large lakes and rivers, as
CORF suggests. The Commission will continue to prohibit 6 GHz devices,
[[Page 11387]]
including VLP devices, from operating on oil platforms because oil
platform locations tend to be concentrated in areas where the passive
and active sensing of EESS operations are conducted.
Technical Rules
In the 6 GHz Second Order, the Commission adopted rules that
permitted VLP devices to operate in the U-NII-5 and U-NII-7 bands at
power levels up to -5 dBm/MHz EIRP PSD and 14 dBm EIRP. The Commission
determined that the risk of harmful interference to incumbent services
in those bands was insignificant for VLP devices operating at that
power level. As a natural outgrowth of that determination, in the 6 GHz
Second FNPRM, the Commission proposed to permit VLP devices to operate
in the U-NII-6 and U-NII-8 bands without geofencing. In the Third
Report and Order, the Commission is adopting this proposal.
Many of the proponents arguing to expand VLP operations to the U-
NII-6 and U-NII-8 bands without geofencing suggest no changes to the
technical rules governing VLP U-NII-5 and U-NII-7 operations. Several
commenters, as discussed in more detail below, suggest modification to
the rules that will apply to VLP operation throughout the 6 GHz band.
To the extent that the Commission did not seek comment on those rule
changes in the 6 GHz Second FNPRM, the Commission is not able to
consider applying them to U-NII-5 and U-NII-7 VLP operations. In
addition, the Commission believes that having uniform rules that apply
to all VLP operations will be of great benefit because it will make
product development easier and lead to economies of scale that will
reduce cost. For this reason, the Commission is adopting identical
technical rules for VLP operations in the U-NII-6 and U-NII-8 bands as
currently apply to such operations in the U-NII-5 and U-NII-7 bands.
However, the 6 GHz Second FNPRM did seek comment on making several
changes to the VLP rules. The Commission sought comment on any
adjustment needed to the VLP device rules to adequately protect C-V2X
operations in vehicles. The Commission also sought comment on relaxing
the restrictions regarding VLP use on aircraft and on oil platforms and
on providing additional flexibility for in-vehicle use. The Commission
defers action on all of these 6 GHz Second FNPRM proposals.
VLP Power Levels. The Wi-Fi Alliance and the IEEE 802 LAN/MAN
Standards Committee support increasing the permitted power for VLP
devices to 1 dBm/MHz with a total EIRP of 14 dBm without use of a
geofencing system. IEEE 802 LAN/MAN Standards Committee states this
would contribute to global harmonization of VLP devices and claims that
this increased power spectral density for 20 and 40 megahertz wide
channels would not cause any risk to incumbent services as these
channel sizes may not be widely used. The Commission determined the
power levels for VLP devices in the 6 GHz Second Order based on an
extensive record examining the potential for these devices to cause
harmful interference to microwave receivers. No commenters submitted
additional technical analysis examining interference to microwave
receivers, and the simulation submitted by Apple, Broadcom, et al. of
interference to ENG central receive sites assumed a VLP power of -5
dBm/MHz. Therefore, the record does not support adjusting the power for
VLP device operations.
Firmware Download. AT&T suggests that all new unlicensed devices be
required to accept mandatory firmware updates that alter their
operating parameters, which will allow unlicensed performance to be
changed in the future, enhancing efficiency and improving spectrum
management. AT&T claims this would be consistent with the National
Telecommunications and Information Administration's (NTIA) Commerce
Spectrum Management Advisory Committee's recommendation that rules for
unlicensed devices be designed to avoid creating obstacles to future
reallocation of the band. APCO also supports requiring, wherever
possible, that unlicensed devices be capable of modification through
over-the-air firmware updates as the harm resulting from interference
from unlicensed devices is potentially irreversible. Sirius XM also
advocates that new unlicensed devices be capable of changing operating
parameters through over-the-air firmware updates to address
interference to its satellite radio system from unlicensed devices that
are in the hands of consumers. Utilities Technology Council recommends
that the Commission require all new unlicensed devices to accept
mandatory firmware updates that alter their operating parameters to
allow devices to be changed in the future for enhanced efficiency and
improved spectrum management.
While AT&T and others assert that requiring unlicensed devices to
be capable of firmware updates could have many benefits, such as
permitting devices to adjust their operations to account for changing
priorities in spectrum demand and evolving technology capabilities or
to address interference issues, such a mandate could be complex and was
not raised in the 6 GHz Second FNPRM. Accordingly, 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 VLP devices in the U-
NII-6 and U-NII-8 bands it does not believe such a mandate is
necessary. Therefore, the Commission will not impose a firmware update
mandate on VLP devices. However, the Commission notes that the vast
majority of today's devices have capability for firmware updates as
manufacturers routinely make changes and upgrades to correct bugs,
enable more efficient operation, or add capabilities. Thus, even absent
a Commission mandate, the Commission expect that most, if not all, VLP
devices will have the ability to receive firmware updates, including
updates to change a device's ability to transmit on certain
frequencies, if such an update is necessary.
Transmit Power Control (TPC). The VLP rules require that VLP
devices employ a TPC mechanism that has the capability to operate at
least 6 dB below the maximum -5 dBm/MHz EIRP PSD. The Ultra Wide Band
Alliance suggests that the Commission expand the TPC requirement beyond
the 6 dB level. The Ultra Wide Band Alliance notes there are many
benefits to using only the power required for a given link, such as
reducing the area that could be impacted, increasing device density,
and increasing the overall capacity of the band. While the Ultra Wide
Band Alliance encourages the Commission to consider technical
requirements for use of TPC that will ``encourage innovation in
intelligent TPC as part of link adaptation schemes,'' it does not
provide any concrete proposal on what specific TPC rules the Commission
should require. Without a specific proposal, the Commission is unable
to evaluate the merits of their request or the impact it would have on
VLP operations.
Benefits and Cost
In the 6 GHz Second FNPRM, the Commission sought comment on whether
allowing VLP devices in the U-NII-6 and U-NII-8 bands will yield
comparable benefits to those that stem from allowing VLP devices in the
U-NII-5 and U-NII-7 bands in the 6 GHz Second Order. The Commission
tentatively concluded that at a
[[Page 11388]]
minimum the benefits would be in proportion to the amount of spectrum
in the U-NII-6 and U-NII-8 bands relative to the amount of spectrum in
the U-NII-5 and U-NII-7 bands. No commenter objected to this
methodology so the Commission will estimate benefits on that basis.
The 6 GHz Second Order found a lower bound of the benefit of
opening the U-NII-5 and U-NII-7 bands to unlicensed use to be $2
billion. The Commission expects unlicensed uses in the U-NII-6 and U-
NII-8 bands to be similar, but with less megahertz of spectrum involved
compared to the U-NII-5 and U-NII-7 bands. To approximate a new lower
bound of benefits, the Commission therefore multiplies the ratio of the
sum of megahertz of spectrum in the U-NII-6 and U-NII-8 bands to the
sum of megahertz of spectrum in the U-NII-5 and U-NII-7 MHz bands by $2
billion, resulting in $820 million of expected benefits. This lower
bound also does not include any benefits that may come from creating a
large contiguous band of spectrum for unlicensed use, which may allow
greater speed and decreased latency. In any case, these benefits will
be well in excess of the costs that the Commission estimates.
Because any changes to the design of VLP devices will be voluntary
for device manufacturers, the rules that the Commission promulgates do
not have net cost implications for the existing unlicensed device
ecosystem. Manufacturers will change designs only if the additional
revenue from taking advantage of the U-NII-6 and U-NII-8 bands
outweighs the costs of redesign. And because the harmful interference
risk to incumbent operators is insignificant and the Commission is not
imposing any specific requirements on any incumbent operator, there are
also no cost implications on them. Thus, by promulgating these rules to
enable VLP devices to operate in the U-NII-6 and U-NII-8 portions of
the 6 GHz band, significant economic benefits will be bestowed on the
American public.
Table of Frequency Allocations
Finally, the Commission takes this opportunity to reinstate the
text of international footnotes 5.458A and 5.458B in the Table of
Frequency Allocations (Table), Sec. 2.106 of its rules. This text was
inadvertently removed when the Commission implemented formatting
changes to accommodate the Office of the Federal Register's publication
guidelines, even though the underlying citations to these footnotes
continued to be printed in the graphical portion of the Table under
both the International Table and the United States Table columns.
Because this change is editorial and does not alter the substance of
these pre-existing footnotes, the Commission finds good cause to
conclude that notice and comment are not necessary for its adoption.
Ordering Clauses
Accordingly, it is ordered, 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 Third Report and Order is hereby adopted.
It is further ordered that the amendments of the Commission's rules
as set forth in Appendix A of the Third Report and Order are adopted,
effective 60 days from the date of publication in the Federal Register.
It is further ordered that the Office of the Secretary, shall send
a copy of the Third 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 Office of Managing Director,
Performance Program Management, shall send a copy of the Third Report
and Order in a report to be sent to Congress and the Government
Accountability Office pursuant to the Congressional Review Act, 5
U.S.C. 801(a)(1)(A).
List of Subjects
47 CFR Part 2
Communications, Communications equipment, Radio, Satellites.
47 CFR Part 15
Communications equipment, Radio.
Federal Communications Commission.
Marlene Dortch,
Secretary.
Final Rules
For the reasons discussed in the preamble, the Federal
Communications Commission amends 47 CFR parts 2 and 15 as follows:
PART 2--FREQUENCY ALLOCATIONS AND RADIO TREATY MATTERS; GENERAL
RULES AND REGULATIONS
0
1. The authority citation for part 2 continues to read as follows:
Authority: 47 U.S.C. 154, 302a, 303, and 336, unless otherwise
noted.
0
2. Amend Sec. 2.106 by adding paragraphs (b)(458)(i) and (ii) to read
as follows:
Sec. 2.106 Table of Frequency Allocations.
* * * * *
(b) * * *
(458) * * *
(i) 5.458A In making assignments in the band 6700-7075 MHz to space
stations of the fixed-satellite service, administrations are urged to
take all practicable steps to protect spectral line observations of the
radio astronomy service in the band 6650-6675.2 MHz from harmful
interference from unwanted emissions.
(ii) 5.458B The space-to-Earth allocation to the fixed-satellite
service in the band 6700-7075 MHz is limited to feeder links for non-
geostationary satellite systems of the mobile-satellite service and is
subject to coordination under No. 9.11A. The use of the band 6700-7075
MHz (space-to-Earth) by feeder links for non-geostationary satellite
systems in the mobile-satellite service is not subject to No. 22.2.
* * * * *
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 revising the definition of ``Very low power
device'' to read as follows:
Sec. 15.403 Definitions.
* * * * *
Very low power device. For the purpose of this subpart, a device
that operates in the 5.925-7.125 GHz band and has an integrated
antenna. These devices do not need to operate under the control of an
access point.
0
5. Amend Sec. 15.407 by revising paragraphs (a)(9) and (d)(10) to read
as follows:
Sec. 15.407 General technical requirements.
(a) * * *
(9) For very low power devices operating in the 5.925-7.125 GHz
band, the maximum power spectral density must not exceed -5 dBm e.i.r.p
in any 1-megahertz band and the maximum e.i.r.p must not exceed 14 dBm.
* * * * *
(d) * * *
(10) Very low power devices operating in the 5.925-7.125 GHz band
shall employ a transmit power control (TPC) mechanism. A very low power
device is required to have the capability to operate at least 6 dB
below the maximum EIRP PSD value of -5 dBm/MHz.
* * * * *
[FR Doc. 2025-02962 Filed 3-5-25; 8:45 am]
BILLING CODE 6712-01-P