[Federal Register Volume 76, Number 224 (Monday, November 21, 2011)]
[Rules and Regulations]
[Pages 71892-71908]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2011-30045]


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FEDERAL COMMUNICATIONS COMMISSION

47 CFR Part 15

[ET Docket No. 04- 37; ET Docket No. 03-104; FCC 11-160]


Broadband Over Power Lines

AGENCY: Federal Communications Commission.

ACTION: Final rule.

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SUMMARY: This document affirms the Commission's rules for Access 
Broadband over Power Line (Access BPL) systems. The Commission also 
makes certain minor modifications to improve and clarify the rules. 
These rules provide an appropriate balance between the dual objectives 
of providing for Access BPL technology that has potential applications 
for broadband and Smart Grid while protecting incumbent radio services 
against harmful interference.

DATES: Effective December 21, 2011.

ADDRESSES: Federal Communications Commission, 445 12th Street SW., 
Washington, DC 20554.

FOR FURTHER INFORMATION CONTACT: Anh Wride, Office of Engineering and 
Technology, (202) 418-0577, [email protected].

SUPPLEMENTARY INFORMATION: This is a summary of the Commission's Second 
Report and Order, ET Docket Nos. 04-37 and 03-104, FCC 11-160, adopted 
October 20, 2011 and released October 24, 2011. The full text of this 
document is available for inspection and copying during normal business 
hours in the FCC Reference Center (Room CY-A257), 445 12th Street SW., 
Washington, DC 20554. The complete text of this document also may be 
purchased from the Commission's copy contractor, Best Copy and 
Printing, Inc., 445 12th Street SW., Room, CY-B402, Washington, DC 
20554. The full text may also be downloaded at: http://www.fcc.gov.
    People with Disabilities: To request materials in accessible 
formats for people with disabilities (braille, large print, electronic 
files, audio format), send an email to [email protected] or call the 
Consumer & Governmental Affairs Bureau at (202) 418-0530 (voice), (202) 
418-0432 (tty).

Summary of the Second Report and Order

    1. In this Second Report and Order (Second Order), the Commission 
fundamentally affirms its rules for Access Broadband over Power Line 
(Access BPL) systems. The Commission also makes certain minor 
modifications to improve and clarify the rules. These rules provide an 
appropriate balance between the dual objectives of providing for Access 
BPL technology that has potential applications for broadband and Smart 
Grid while protecting incumbent radio services against harmful 
interference.
    2. The Commission adopted rules for Access BPL systems in 2004 and 
affirmed those rules in 2006. The BPL rules were challenged by the 
national association for amateur radio, formally known as the American 
Radio Relay League (ARRL) in the United States Court of Appeals for the 
District of Columbia in ARRL v. FCC. In ARRL v. FCC, the court directed 
the Commission to: (1) Make part of the rulemaking record unredacted 
versions of several staff technical studies which the Commission 
considered in promulgating the rules, (2) provide a reasonable 
opportunity for public comment on those studies, and (3) provide a 
reasoned explanation of its choice of the extrapolation factor for use

[[Page 71893]]

in measuring radiated emissions from Access BPL systems. In response, 
the Commission issued a Request for Further Comment and Further Notice 
of Proposed Rulemaking in this proceeding (RFC/FNPRM). In the RFC/
FNPRM, the Commission took its first step in responding to the 
directives of the court in ARRL v. FCC and also took that opportunity 
to review the Access BPL extrapolation factor and propose certain 
changes to the BPL technical rules that appeared appropriate in view of 
new information and further consideration of this matter. In this 
Second Order, the Commission completes its action addressing the 
court's concerns and its proposals in the RFC/FNPRM. It finds that the 
information submitted in response to the RFC/FNPRM does not warrant any 
changes to the emissions standards or the extrapolation factor. 
However, the Commission is making several refinements to its Access BPL 
rules. In particular, it is: (1) Modifying the rules to increase the 
required notch filtering capability for systems operating below 30 MHz 
from 20 dB to 25 dB; (2) establishing a new alternative procedure for 
determining site-specific extrapolation factors generally as described 
in the RFC/FNPRM, and (3) adopting a definition for the ``slant-range 
distance'' used in the BPL measurement guidelines to further clarify 
its application. The Commission finds that the benefits of the changes 
to the rules outweigh their regulatory costs.
    3. Throughout this proceeding and in its appeal to the court, the 
ARRL has argued that more restrictive technical standards are needed to 
protect the amateur radio service from interference caused by leakage 
of radiofrequency (RF) emissions from Access BPL systems. The 
Commission initially crafted rules for BPL systems that were based on 
our existing emission standards for carrier current communications 
systems--narrow-band devices that couple RF energy onto power line 
wiring for communication purposes--with a number of additional 
requirements to promote avoidance and resolution of harmful 
interference to licensed services that might occur in the context of 
BPL operations. The Commission subsequently affirmed those rules in 
response to petitions for reconsideration by various parties, including 
ARRL. In this process, it has specifically rejected as unnecessary 
repeated requests by ARRL for tighter emissions controls on Access BPL 
operations. In response to the court's direction, it provided 
opportunity in the RFC/FNPRM for interested parties to address the BPL 
technical rules and the information developed by our staff that we 
considered in establishing those rules, explained its rationale for the 
extrapolation factor used in measuring BPL emissions, expressed its 
tentative satisfaction with the extrapolation factor adopted, while 
soliciting comment on whether another value would be more appropriate, 
and proposed a procedure for determining site-specific extrapolation 
factors. The Commission has completed its response to issues raised 
under the court's directive.
    4. The Commission has established a regime of rules for Access BPL 
systems that will provide a robust environment for the development and 
deployment of this important new technology option for delivery of 
broadband internet/data services while at the same time minimizing the 
potential for interference to licensed services caused by leakage from 
power lines of the RF energy used by BPL transmissions. As observed in 
the BPL Order, there is some potential for increased harmful 
interference from BPL operations, particularly in locations within a 
short distance of the power lines used by this technology. Consistent 
with our responsibilities for managing the interference potential of 
devices which can interfere with radio under Section 302 of the 
Communications Act, the Commission has developed a set of rules for BPL 
devices and systems that attempts to minimize instances of interference 
while allowing BPL systems to operate in a viable manner to serve the 
needs of the American public. In this regard, the Commission has stated 
and continues to hold that, on balance, the benefits of Access BPL for 
bringing broadband services to the public are sufficiently important 
and significant so as to outweigh the limited increase in potential for 
harmful interference that may arise. The Commission also agrees with 
NTIA that while some cases of harmful interference may be possible from 
Access BPL emissions at levels at or below the part 15 limits, the 
potential benefits of Access BPL service warrant acceptance of a 
negligible risk of harmful interference that can be managed and 
corrected as needed on a case-by-case basis.
    5. To minimize the potential for harmful interference, facilitate 
its resolution where it may occur, and address cases where its possible 
occurrence could impact critical services, the Commission adopted 
additional regulatory measures beyond the emissions limits in the part 
15 rules. These additional measures generally require Access BPL 
operators to reduce emissions or avoid operation on certain frequencies 
or in certain locations in order to protect licensed services, to use 
equipment that can alter its operation by changing frequencies to 
eliminate harmful interference, to provide information that will assist 
the public in identifying locations where Access BPL operations are 
present and provide notice to radio users before commencing local BPL 
operations in a publicly accessible database. In this manner, the 
Access BPL rules provide an effective means for limiting harmful 
interference and ensuring that any instances of harmful interference 
that may occur can be quickly identified and resolved. As emphasized in 
the BPL Order, Access BPL systems will continue to be treated as 
unlicensed part 15 devices and as such will be subject to the 
conditions in Sec.  15.5(b) of the rules that they not cause harmful 
interference and that they cease operation if they do cause such 
interference, as required by our rules. Upon examination of the 
information and comments received in response to the RFC/FNPRM, the 
Commission continues to believe that these measures are adequate and 
appropriate for managing the potential for harmful interference to all 
licensed radio services that operate on the bands used internally by 
BPL systems, including the amateur radio service.
    6. The Commission is not persuaded by ARRL's newest technical 
submissions, including the reports/standards referenced in its November 
2010 and June 2011 ex parte comments, or its assertions regarding the 
information in the unredacted presentations and in the additional 
information it recently introduced into the record in July 2009 that 
our assessment of the interference potential from BPL operations was 
incorrect or inappropriate, or that modifications to the BPL emissions 
limits and other technical rules to provide additional protection for 
the amateur service are warranted. While there is much valuable and 
valid information and analysis in ARRL's technical presentations, there 
are additional considerations that previously led us to draw different 
conclusions and still lead us to maintain those conclusions now.
    7. With regard to the redacted portions of the staff presentations 
and the preliminary information from early staff work that was released 
in July 2009, the Commission was, of course, aware of that content and 
it was also aware of other considerations and facts that bear on the 
various BPL technical issues. Notwithstanding ARRL's apparent belief 
that the full content of the staff presentations should have led

[[Page 71894]]

us to the conclusion it prefers, the Commission found, and continues to 
find, differently with respect to the regulatory measures that are 
needed to protect the amateur service from interference from BPL 
operations. The presentations in those informally conducted experiments 
were part of our initial internal investigation of BPL and, while there 
is value in them, they are not the sole source of our information on 
BPL performance. In this regard, the Commission considered all of the 
available information on BPL systems and their performance, submissions 
in the comments and other publicly available information. It also 
observes that some of the staff presentations on which ARRL focuses 
were of experimental systems that used early implementations of BPL 
equipment, developed before the BPL Order, that do not appear to have 
complied with the new rules; additionally, information on other system 
implementations, particularly our work with the Manassas, VA system, 
showed different performance characteristics than the systems ARRL 
criticized. In some cases, ARRL simply (and incorrectly) draws 
different conclusions from those presentations than we do. Also, the 
assessments and recommendations in the redacted portions of the 
presentations merely reflect the views of the Laboratory engineers who 
performed the testing and analysis; they do not necessarily reflect the 
consensus view of other engineers, the management of the Laboratory or 
of OET. Indeed, individual views are often conflicting, but are 
encouraged in the interest of producing vigorous debate to lead to a 
thoroughly considered recommendation and decision.

The Potential for Harmful Interference

    8. In the BPL Order, the Commission, with concurrence from NTIA, 
concluded that the current emission limits will restrict Access BPL 
systems to low emitted field strength levels in comparison to the 
signals of licensed radio operations. It found that the effect of these 
limits will be to constrain the harmful interference potential of these 
systems to relatively short distances from the power lines that carry 
the BPL signals. The Commission also recognized that some radio 
operations in the bands being used for Access BPL, such as those of 
amateur radio licensees, may occur at distances sufficiently close to 
power lines as to make harmful interference a possibility. The 
Commission stated that it believed those situations can be addressed 
through interference avoidance techniques by the Access BPL provider 
such as frequency band selection, notching, or judicious device 
placement, and it adopted rules to facilitate such solutions.
    9. The Commission agreed with ARRL that Access BPL on overhead 
lines is not a traditional point-source emitter, but not with its 
argument that Access BPL devices would cause power lines to act as 
miles of transmission lines all radiating RF energy along their full 
length. In this regard, the Commission observed that the part 15 
emission limits for carrier current systems have proven very effective 
at controlling interference from such systems. Also, it indicated that 
the design and configuration of Access BPL systems would be 
inconsistent with the development of cumulative emission effects for 
nearby receivers. The Commission further concluded that because the BPL 
emissions level decreases significantly with distance perpendicular 
from the line, the potential for interference also decays rapidly with 
distance from the line.
    10. The Commission recognized that Access BPL systems present 
concerns for licensed users in the high frequency (HF) and lower 
portions of the very high frequency (VHF) bands, given the propagation 
characteristics of RF signals in the range of frequencies being used 
for these systems, the diversity of users of these frequencies, and the 
fact that Access BPL devices could be installed at many locations in an 
area. While it concluded that there is little likelihood that harmful 
interference would occur from Access BPL operations at the signal 
levels allowed under the current part 15 emission limits, it 
acknowledged that such interference could occur in limited situations 
despite the intentions of BPL operators. To address this interference 
potential, the Commission required BPL operators to comply with 
additional interference mitigation techniques. It stated that such 
steps should be taken particularly in those cases where the occurrence 
of interference would affect critical services or where interference 
could be anticipated to occur. The interference mitigation measures for 
critical services include exclusion from operating on certain frequency 
bands and exclusion from operation in certain areas. For all services, 
the interference mitigation provisions require that BPL system 
operators have the ability to remotely cease operation or apply 
frequency avoidance (notching) on bands where licensed services are 
receiving interference. BPL operators were required to be able to notch 
their operations on affected bands to a level 20 dB below the part 15 
emissions limit for frequencies below 30 MHz (i.e., 1/100th of the 
emissions limits for other unlicensed unintentional radiators).
    11. In the BPL Reconsideration Order, the Commission affirmed its 
selection of 20 dB below the part 15 emissions limit as the minimum 
notching capability for frequencies below 30 MHz. It also revised the 
rules to specify that where an Access BPL operator implements such 
notching, the operator need not provide further protection to mobile 
operations, nor will the operator be required to resolve complaints of 
harmful interference to mobile operations by taking steps over and 
above implementing the ``notch.'' The Commission found that, while this 
level may be above the noise floor, reception of signals in mobile 
operating conditions is generally not reliable at levels at or below 
that level and thus does not warrant protection.
    12. The Commission disagrees with ARRL that the recently released 
materials show interference potential from Access BPL systems to be 
significantly greater than that which we anticipated in the BPL Order, 
that such interference will be preclusive of amateur operations over 
large areas, or that the current rules are not adequate to resolve any 
interference that might occur. Rather, ARRL's in-depth focus on that 
material is in some aspects consistent with the Commission's own 
assessments, in other aspects incorrect, and, importantly, in many 
aspects does not account for the real world conditions affecting the 
propagation of RF emissions at HF frequencies. While ARRL provides 
significant information on the standard engineering principles 
concerning the attenuation rate of emissions from line emitters, it is 
mistaken as to how the attenuation rate should be viewed for purposes 
of measuring BPL emissions. In this regard, the Commission again 
concludes that 40 dB/decade is a best estimate of the expected 
attenuation rate/extrapolation factor in the conditions in which 
measurements are made under the Access BPL measurement guidelines. The 
Commission finds no information in the comments or the newly submitted 
information in ARRL's November 2010 and June 2011 ex parte submissions 
that would warrant modification of the Access BPL rules to require 
notching of all amateur bands at notch depths of at least 35 dB, or 
otherwise provide additional protection for the amateur service. 
However, in reviewing the requirement that Access BPL systems be 
capable of reducing their emissions by 20 dB in a given frequency band 
and current developments in BPL equipment, the

[[Page 71895]]

Commission now finds that it would be appropriate to increase this 
required ``notching'' capability by 5 dB, to 25 dB for BPL systems 
operating below 30 MHz. It responds to the comments with respect to 
each of these sets of materials sequentially listed here.

Unredacted Staff Presentations and Newly Submitted Materials

    13. In its comments, ARRL argues that the unredacted staff 
presentations show that:
    i. Access BPL is not a point-source emitter; it is a distributive 
system that has significant interference potential over a wide area at 
significant distances from (and along) the power line carrying BPL 
signals. It contends that the Commission's measurements show that there 
is virtually no signal decay along the power line 230 meters from the 
coupler.
    ii. The proper distance extrapolation factor for assumed signal 
decay with distance from the power line is much closer to 20 dB/decade 
of distance (20 log R) than to the 40 dB/decade of distance (40 log R) 
adopted by the Commission for frequencies below 30 MHz.
    iii. Access BPL has a considerably higher interference potential to 
licensed radio services than the Commission concluded in the BPL Order 
if operated at the maximum radiated emission levels permitted by the 
Commission's part 15 rules (and the BPL rules adopted in the BPL 
Order). Specifically, interference to licensed mobile radio receivers 
is very likely for very long distances along a power line. The 
presentations also show that systems operating at the part 15 emission 
limits will be at least 25-35 dB stronger than the median values of 
man-made noise at 30-meters distance. Extrapolating this to a mobile 
antenna closer to the lines results in an even higher noise level.
    iv. The Commission erred in concluding that mobile Amateur stations 
would be protected from interference if, in response to an interference 
complaint, the BPL operator reduced the BPL radiated emission level 
from the offending portion(s) of the BPL system by 20 dB below the 
maximum radiated emission level permitted for part 15 devices 
generally. That remedy falls far short of reducing BPL noise to the 
level of ambient noise in residential environments found by 
Commission's technical staff, and falls far short of reducing BPL 
wideband noise levels to the point that mobile communications can be 
conducted in areas substantial distances from the power line.
    v. Measurement of BPL radiated emissions should be done at heights 
not lower than in the same horizontal plane as the overhead power line.
    14. First, the Commission agrees with ARRL that a BPL system does 
not behave as a point-source emitter. Neither, however, can it be 
analyzed as a line emitter. Analysis and prediction of RF propagation 
in the HF frequency region is extremely complex and difficult, and 
particularly at locations close to the ground, as the Commission, ARRL 
and many other commenters have acknowledged throughout this proceeding. 
The Commission's intent in the BPL Order was not to say that power 
lines are point-source radiators, but rather simply that the 
interference potential lessens with distance down the line from the 
coupler--though this occurs at rates that can vary significantly with 
power line topology.
    15. ARRL points out that one of the video files in the staff 
materials released by the Commission in July 2009 shows interference to 
mobile reception of signals in the amateur 20-meter band (14.0-14.35 
MHz). Specifically, it states that the video of the Briarcliff Manor 
system recorded on August 17, 2004 (Briarcliff Video 5) shows 
in a graphic, compelling manner the severe and constant interference 
caused by the BPL system to amateur reception over huge geographic 
areas which obviously precluded essentially all Amateur HF 
communications in the area. It submits that no objective observer of 
this video could possibly conclude that the level of BPL radiated 
emissions permitted by the Commission's Part 15 rules is acceptable. 
ARRL is correct that the interference that is apparent on Briarcliff 
Video 5 is not acceptable and would not be permissible under 
either our part 15 rules or the system operator's experimental license. 
However, while interference can occur from BPL operations along a 
stretch of power lines as shown in that and other videos in the 
preliminary materials released in July 2009, the Commission did not and 
do not find this example to substantiate a need for more restrictive 
rules on BPL systems. First, it does not appear that any of the 
mitigating features that are required in the rules had been applied to 
this system. In addition, our staff did contact the licensee about 
interference from that system several times over the course of its 
operation and the operator took steps first to cease operation on the 
amateur frequencies and then to install new equipment that had notching 
capability. Subsequent examination of that system by field agents of 
the Commission's Enforcement Bureau found no interference, which 
substantiates the effectiveness of our rules when properly observed. 
Also, as indicated by the primary and secondary title screens of 
Briarcliff Video 5, the system was notched only in the 20-
meter amateur band, and not in the 15-meter amateur band, for which 
that video was recorded. Thus, the Commission did not and do not 
consider the interference that appears in Briarcliff Video 5 
to be representative of the performance of a system operating in 
accordance with the set of rules it set forth for Access BPL systems.
    16. The Commission also sees no merit in ARRL's argument that 
statements on the same presentation slide concerning an interference 
problem from the Phonex carrier current system to ARINC aeronautical 
communications and opining that compliant Access BPL ``may be worse'' 
should have served as a factor in its decision on protection for the 
amateur service. In the BPL Order, the Commission recognized the 
critical nature of aeronautical communications and, given the free 
space propagation path from a power line to an aircraft, excluded 
Access BPL systems from operating on frequencies used by that service. 
With respect to the Phonex case, the Commission also observes that the 
Phonex system at issue might not have been the source of the 
interference with ARINC's communications and its performance therefore 
cannot be used as an empirical basis for establishing any benchmarks 
with respect to the interference potential of BPL systems.
    17. ARRL next observes that another presentation slide in the 
Briarcliff Manor presentation recommends that the Commission ``impose 
[a] 5 dB height correction [factor]'' on measurements and a ``20 log R 
extrapolation factor'' if it is going to allow BPL on medium voltage 
(MV) overhead power lines and should use a 20 dB/decade extrapolation 
factor for signal decay with distance from the power line. It observes 
that the presentation states that this ``reduces interference [from 
BPL] to fixed stations.'' Basing the BPL emissions limits and 
measurement procedures on an attenuation rate of 1/R, i.e., 20 dB/
decade would, of course, reduce signal levels and thereby provide 
additional protection to licensed services against interference. The 
Commission notes that the slide in question does not provide a 
``recommendation'' as claimed by ARRL, rather, it only presented 
several options for other staff and management to consider in its 
deliberations. Further, as the Commission concluded previously, it does 
not believe that such

[[Page 71896]]

additional protection is needed or warranted, but rather hold that the 
part 15 ``no interference requirement,'' the part 15 emissions limit 
for carrier current systems, and the interference mitigation measures 
it adopted in the BPL Order collectively provide sufficient protection 
to licensed services from the potential for harmful interference from 
Access BPL operations. The Commission also continues to find that the 
attenuation rate of emissions from power lines is typically higher than 
20 dB/decade and varies with location. At distances within 30 meters of 
the power line and when using the slant-range measurement procedure 
prescribed in our measurement guidelines, 1/R\2\, i.e., 40 dB/decade, 
properly describes the expected attenuation rate at frequencies below 
30 MHz, and variability around that rate is also expected.
    18. It is also important to understand, as the Commission discussed 
in the RFC/FNPRM and ARRL largely ignores, that RF propagation in the 
lower frequencies ranges, and particularly at frequencies below 30 MHz, 
is greatly affected by environmental factors, so that there is 
significant variability in propagation from place to place. These 
include ground absorption and conductivity, terrain, vegetation, and 
the presence of structures and other man-made objects, including 
additional power lines arrayed on pole/towers in the near-field of 
emissions from a power line carrying Access BPL transmissions. In some 
cases, emissions from BPL systems that are expected to be compliant 
with the rules will attenuate with distance at relatively high rates 
and be well below the part 15 limits while emissions from other 
systems, or even from the same system but at a different location, will 
attenuate at a relatively lower rate and exceed the part 15 limits. The 
Commission is aware of these variabilities in this complex operating 
environment and to account for it, has adopted additional provisions 
for mitigating harmful interference that are set forth in the rules. In 
addition, recognizing this variability, it did not base our assessment 
of interference potential on any standard performance factor, such as 
an attenuation rate by itself, but rather on the successful past 
performance of our existing standards and the availability of suitable 
approaches for managing the potential for harmful interference and 
correcting any harmful interference that may occur.
    19. The Commission has also fully considered the issue of how to 
measure Access BPL emissions, including whether a 5 dB correction 
factor was needed for Access BPL measurements below 30 MHz. In the BPL 
Order, it concluded that the existing measurement procedure that 
provides for measurement of the magnetic field at 1-meter height with 
no correction factor was appropriate for measurements in that frequency 
region. There is no additional information in the presentation 
summaries that leads us to find that this decision should be changed.
    20. ARRL points out that slide 20 of the Briarcliff Manor 
presentation listed options of notching or mandatory advance 
coordination for protection of low-VHF public safety channels and that 
the Commission did not adopt either of those options but instead put in 
place a notification requirement. It also observes that the same slide 
listed the 50-54 MHz amateur band that is typically used for both 
mobile and fixed operations and the Commission did not acknowledge the 
interference potential to amateur operations in that band and offered 
no remedy for it. In the BPL Order, the Commission determined that 
public safety systems, because of the often critical and/or safety-of-
life nature of the communications they provide, merit the additional 
protection of advanced notice of BPL operations. The Commission stated 
that an advance notification would provide a public safety operator 
with an opportunity to assess whether there are portions of its 
geographic area of responsibility about which it should make special 
arrangements with the Access BPL operator in order to avoid 
interference. The Commission did not address the frequencies used by 
the amateur service on an individual basis, but rather concluded that 
amateur radio frequencies generally do not warrant the special 
protection of frequency exclusion that was afforded frequencies 
reserved for international aeronautical and maritime safety operations.
    21. ARRL observes that slide 21 of the Briarcliff Manor 
presentation predicts the potential for BPL to cause interference to 
mobile operations to be ``high'' to ``very high.'' It further observes 
that the same slide has a table indicating that the interference 
distance to fixed stations would be 62 meters at 2-8 MHz and 400 meters 
at 8-30 MHz in areas where the noise levels were at the International 
Telecommunication Union (ITU) ``residential'' level. It contrasts these 
statements with our findings in the BPL Order that the potential of 
Access BPL systems was ``low'' and observes that in the case of mobile 
communications where a vehicle is close to the power lines, the 
potential for interference will indeed be higher. While the Commission 
again recognize that at some locations (including where nearby antennas 
are located above the height of the power line) the attenuation rate of 
Access BPL emissions will be lower and at other locations it will be 
higher, these levels are consistent with our interpretations that the 
interference potential is low such that it can be managed adequately 
with the additional interference mitigation measures and the ``no 
harmful interference provisions'' of part 15 that are also in our 
rules. In this regard, the distances from a power line to an amateur 
fixed receiver will be sufficiently short that if harmful interference 
were to occur, the recipient could readily identify its source and 
request that it be resolved. The Commission observes that International 
Broadband Electric Communications, Inc. (IBEC), a major operator of 
Access BPL systems, reports (with confirmation by ARRL in its comments) 
that it has been communicating with the local amateurs and emergency 
services in the areas it covers to implement a successful interference 
resolution process. It states that it has been able to resolve 
interference complaints, as they arise, under the framework of the 
existing Access BPL rules. This information provides confirmation of 
the processes and requirements the Commission established, when used in 
practice, are adequate to prevent most cases of harmful interference to 
licensed services, and to resolve quickly any instances of harmful 
interference that do occur.
    22. Spectrum Notching. The rules provide for mitigation of BPL 
interference where it may occur by notching. In the BPL Order and the 
BPL Reconsideration Order, the Commission found that, for frequencies 
below 30 MHz, a 20-dB notch would appropriately address any harmful 
interference that might occur to mobile operations, given both the low 
signal levels allowed under the part 15 emission limits and the fact 
that a mobile transceiver is generally only in one place for a limited 
period and can readily be re-positioned to provide some separation from 
the Access BPL operation.
    23. In its comments, ARRL argues that slide 13 of the Briarcliff 
Manor presentation summary references predictions from the NTIA Phase 1 
Study that show that the noise floor would rise by more than 20 dB at 
nearly all points, and by 30 dB at most points, along a 340-meter 
modeled power line. It also notes that the slide states that in NTIA's 
measurement activities, NTIA took occasional samples of noise power

[[Page 71897]]

along the line with the Access BPL system turned off and found noise 
levels lower than predicted by the ITU for residential areas. ARRL 
therefore contends that the 20-dB standard for the notching requirement 
is insufficient. The Commission initially noted that NTIA's sampling of 
noise power was only at a very limited number of locations and not 
sufficient to serve as the basis for a conclusion that the noise floor 
is lower than the levels recognized by the ITU. Further, there is not 
sufficient information in any of the submissions regarding changes in 
the noise floor to justify a change from our use of the well-
established ITU-recommended levels for the noise floor in different 
environments.
    24. In its November 2010 ex parte submission, ARRL provides 
additional comments that reference several recent domestic and 
international industry and governmental reports/standards to support 
its request for a 35-dB notch of all the amateur frequency bands. These 
documents include: (1) ITU-R Report SM.2158; (2) ITU-T G.9960; (3) IEEE 
P1901-2010; and (4) OFCOM Report on In-Home PLT devices. All of these 
documents mandate or recommend notching of the amateur frequencies. 
ITU-R Report SM.2158 states that the maximum allowable increase in the 
noise floor due to BPL emissions should not exceed 0.5 dB, based on the 
assumption that the fade margin of the amateur service in long distance 
communications is less than 1 dB. Based on this assumption, ARRL argues 
that a notch depth of 34 dB would be required if a 20-dB/decade 
extrapolation of the FCC emission limits is used and a notch depth of 
43 dB would be needed if the existing extrapolation factor of 40-dB/
decade is used.
    25. In re-examining all of the information pertaining to the depth 
of the notching requirement, the Commission now finds that it would be 
appropriate to increase the required notching capability to be 5 dB 
greater than the 20 dB specification it initially adopted. Previously, 
the Commission observed that when operating with a 20-dB notch below 30 
MHz, the maximum allowed emissions from an Access BPL system is 10 
dB[mu]V/m at the part 15 measurement distance of 30 meters, a level 
which is at or only modestly above the noise floor in the HF bands at 
most locations. The Commission's intention was that Access BPL 
emissions in a notched bandwidth would not be significantly greater 
than the background noise at the distances normally used for protection 
against harmful interference from part 15 unlicensed devices. The 
Commission also evaluated the potential for interference at closer 
distances that can occur when conducting mobile communications while 
traveling adjacent to roadside power lines. It observed that when 
extrapolated to values for the typical closest distance of a mobile 
antenna in motion from roadside power lines (approximately 6 meters 
horizontal distance and 8.5 meters vertical distance, for a slant range 
of 10.4 meters) and adjusted for the typical quasi-peak to average 
ratio of 4 dB for BPL devices operating at high duty factor, the part 
15 limit corresponds to a root-mean-squared (RMS) field strength of 44 
dB[mu]V/m for frequencies at or below 30 MHz. A 20 dB reduction would 
limit emissions to 24 dB[mu]V/m. The Commission concluded that given 
the high variability of the noise floor at HF frequencies, where 
increases of as much as 20 dB or more are common, mobile reception of 
relatively weak signals under 24 dB[mu]V/m is generally intermittent 
and not reliable because both the received signal and the ambient noise 
levels vary up and down (the received signal and noise energy levels 
generally do not rise and fall together) as the vehicle moves.
    26. In carefully reviewing the record on this issue, the Commission 
acknowledged ARRL's point that the modeling in the NTIA Phase 1 Study 
predicts that Access BPL emissions on frequencies below 30 MHz that are 
at the part 15 limit would raise the mobile radio noise floor at 15 MHz 
and 25 MHz by 30 dB in 59% of residential locations. After a 20-dB 
notch, the BPL remaining emissions would still produce a noise floor 
increase of about 10 dB for mobile operations in residential locations 
at those frequencies. As the Commission observed in the BPL 
Reconsideration Order, there is considerable variability around the 
median noise level, such that increases of as much as 20 dB are common 
and reduce the reliability of signals at the margin of expected 
reception. While, the Commission continues to believe that the 
significant variability in background noise levels limits the 
reliability of HF signals below 30 MHz such that BPL emissions at a 
level of 24 dB[mu]V/m should not generally be considered harmful 
interference, it also understand that the 20 dB value for noise 
increases due to diurnal and seasonal factors is the maximum expected 
effect and that in many cases the daily variability in the noise floor 
levels will be somewhat less. The Commission have no specific 
information on the distribution of the diurnal and seasonal variability 
of noise floor levels; however, it believes that an increase of 5 dB in 
the required notching capability, or half the 10-dB current margin of 
BPL emissions affecting mobile reception above the residential noise 
floor, according to NTIA's estimates as supported by ARRL, would take a 
more conservative approach and provide protection for amateur mobile 
operations in more instances, while continuing to recognize the 
variability in emissions that limit the service to mobile amateur 
receivers. Given our understanding supported by the assertions in the 
record that most BPL operators are already using notches of at least 25 
dB, the Commission would expect the cost imposed by this requirement to 
be minimal or nil. It finds that the benefits of providing additional 
protection for licensed services outweigh any potential additional 
costs to BPL providers. Such benefits include a more integrated 
environment where BPL devices may share spectrum with licensed users, 
with lesser concerns for potential harmful interference. BPL devices 
bring expanded benefits to electric utility companies by allowing them 
to monitor, and thereby more effectively manage their electric power 
distribution operations. BPL also brings ``last-mile'' delivery of 
broadband services to some rural and underserved areas.
    27. With respect to the new information in ARRL's November 2010 ex 
parte submission, first the Commission is not persuaded that a 0.5 dB 
increase in the noise floor as used in the ITU-R Report SM.2158 is a 
reasonable assumption for the numerous reasons it stated with respect 
to the significant variability in background noise levels at HF 
frequencies. Further, it appears that the 0.5 dB number was used in the 
ITU Report without any discussion, analysis or other explicit 
rationale. The Commission further noted that in its June 2011 ex parte 
submission, ARRL mentions that ITU-R Recommendation SM.1879, which 
refers to the above report, does recommend that stations operating in 
the Amateur Service be protected t*** level such that noise at the 
protected station is not increased by more than 0.5 dB. Although ARRL 
provided calculations to relate the 0.5 dB increase in the noise floor 
with the part 15 limits to arrive at its requested 35-dB notch number, 
it again did not provide a rationale for using a 0.5 dB increase in the 
noise floor as the protection criterion at HF frequencies. With the 
exception of ITU-R Report SM.2158, the reports/standards submitted by 
ARRL in its November 2010 ex parte comments do not include

[[Page 71898]]

any analysis that shows that 35 dB or some other figure is the proper 
level of notching needed to protect amateur operations, but rather 
simply state as their recommendations and requirements a notching depth 
that existing BPL equipment can meet. The Commission also recognizes 
the ARRL's observation in its June 2011 ex parte submission that in the 
IEEE P1901-2010 standard there is a normative requirement for a 30-dB 
notch depth for the FFT OFDM (HomePlug) technology. While this 
voluntary industry standard is apparently being used by manufacturers 
of HomePlug In-House BPL equipment, it is more stringent than is 
necessary for our regulatory purposes and in any case does not apply to 
the Access BPL applications at issue herein. The Commission also does 
not find persuasive ARRL's argument that deeper notching can be 
implemented without adverse impact on the data rates of BPL technology. 
In this regard, the testing on which ARRL bases this claim was on In-
House rather than Access BPL equipment and in any case our principal 
concern is with imposing regulation that is more restrictive than 
necessary rather than simply minimizing the impact that such regulation 
might have on some aspect of BPL equipment or its operation. While the 
Commission duly note the Republic of Korea's decision to require 
permanent notching of the amateur bands, the relevance of that 
determination by that country's regulatory body at that time to our 
present consideration is not readily apparent, and ARRL provides no 
information regarding either the radio environment or the regulatory 
objectives and standards that informed that decision by which the 
Commission might consider how those considerations might affect our own 
decision making.
    28. The Commission recognizes that one of the documents referenced 
by ARRL, IEEE P1901-2010, is an industry standard for both Access and 
In-House BPL equipment authored by nearly a hundred entities that 
include BPL service and equipment providers and that this standard 
describes a 35-dB spectrum notching for compatibility with amateur 
radio services that can be supported by a type of BPL technology known 
as wavelet OFDM, as elucidated by UTC. Further, as ARRL submits, its 
scrutiny of systems listed in the BPL database indicates that existing 
BPL systems in the U.S. are generally notching the entirety of the HF 
amateur allocations, using equipment capable of notch depths of at 
least 35 dB. Thus, it appears that many BPL systems now in operation 
may be voluntarily observing the notch depth and band avoidances that 
ARRL is requesting. While those industry practices are consistent with 
the ARRL's goals in this matter, the Commission nonetheless finds they 
are more stringent than are justified from a regulatory standpoint. In 
this regard, the Commission does not find that an increase in the 
required notching capability to a level above 25 dB is needed to 
protect against interference to amateur or any other licensed services. 
To require that all systems adhere to a de facto industry 35-dB 
notching standard would unnecessarily constrain BPL operators, as 
stated by UTC, and equipment manufacturers who might choose to design 
for a different level of operation that would comply with the notching 
level the Commission has determined will provide adequate protection. 
Further, to require that all of the amateur bands be notched would 
unnecessarily restrict BPL operations in areas/locations where no 
amateur operations are present that could receive interference.
    29. The Commission sees no statistically-valid support for ARRL's 
position that the ambient noise levels have become so low as to 
contradict our conclusion here that a 25-dB notch is generally 
sufficient to protect licensed services. Further, for fixed stations, 
if a 25-dB notch is not sufficient to resolve observed harmful 
interference or other steps to resolve the interference are not 
successful, under Sec.  15.5(c) of the rules, the operator is then, 
upon notification by a representative of the Commission, required to 
cease operation until the interference is corrected. In such cases, the 
interference might perhaps be resolved by using new equipment that 
includes a filter with a notch capability greater than 25 dB. The 
Commission believes, however, that the new 25-dB notching requirement 
will be sufficient to resolve the great majority of cases of harmful 
interference that might occur and therefore do not see a need to 
require that Access BPL systems routinely use equipment with greater 
notching capability.
    30. In changing the notching level to 25 dB, the Commission is 
aware that Access BPL operators have already installed equipment with 
20-dB notching capability in compliance with the rules and that there 
is some inventory of equipment built to that standard which has not yet 
been installed. While it believes that the greater level of protection 
provided by our rule change is prudent in the long term, it has not 
observed any cases to date where the notching afforded by existing 
equipment has not been adequate to resolve interference. Accordingly, 
given the limited number of devices already deployed and manufactured, 
the Commission will not require their replacement or prohibit their 
installation for replacement or in new constructions. In order to 
afford manufacturers time to redesign their equipment to comply with 
the new, more conservative 25-dB notching requirement, the Commission 
will allow an 18-month period from the date this action is published in 
the Federal Register before the requirement becomes effective.
    31. In its reply comments, ARRL submits that IBEC did not resolve 
interference complaints to amateur fixed stations by doing what the 
existing BPL rules require, other than compliance with the general part 
15 requirement to correct any harmful interference. It states that 
instead, IBEC has avoided or resolved the interference by doing two of 
the things that ARRL has requested as modifications to the existing BPL 
rules: (1) IBEC avoided the use of Amateur bands in its installations, 
and (2) it has used state-of-the-art notch depths of 35 dB. The 
Commission observes that avoiding a frequency band where interference 
could occur is certainly an option that is contemplated under the 
rules. Using a notching capability with attenuation of greater than 
that required in the rules where needed is also consistent with the 
general requirement in part 15 rules that a device not cause harmful 
interference. The Commission does not, however, find the fact that 
equipment which can provide 35-dB notching capability is now available 
and IBEC's choice to use such equipment to be indicative that it should 
require that level of notching capability in all instances. Rather, 
while the rules will now require a notching capability of at least 25 
dB, that level of attenuation will only be deemed sufficient for 
resolving harmful interference in the case of mobile operations; the 
system operator is still responsible for resolving harmful interference 
to fixed operations if the 25-dB notch capability is used and the 
interference remains. Under the notching rules the Commission adopted, 
a BPL system operator has the flexibility to install a notching 
capability greater than 25 dB or to implement other measures for 
resolving harmful interference in cases where the 25-dB notch is not 
sufficient. In this regard, IBEC did, in fact, take the steps required 
under Sec.  15.611(c) of the rules--it configured its systems to be 
capable of remotely reducing power by 35 dB and adjusting operating 
frequencies to avoid site-specific, local use of the same

[[Page 71899]]

frequencies by licensed radio operations. A different operator might 
have chosen an alternative approach for complying with this rule.

Preliminary Documents Released in July 2009

    32. Notwithstanding ARRL's contentions, the Commission did consider 
the information in the presentations in the BPL Order and in the 
formulation of our rules for regulating interference from Access BPL 
emissions. There are no new facts, information, or interpretations in 
those presentations or in ARRL's comments that are inconsistent with 
the Commission's previously stated understandings and findings. These 
presentations, as well as other information in this proceeding, show 
that Access BPL operations can raise the RF noise level to levels above 
the noise floor such that they can cause interference to amateur 
operations in the close vicinity of power lines on which the BPL 
signals are carried. As the presentations show, the area of 
interference is essentially limited to distances close to and along the 
power lines. While some interference is possible at locations close to 
the power line, the Commission believes that in the great majority of 
locations, interference will not occur to radio services because either 
propagation conditions limit the range of the Access BPL emissions or 
there is no licensed amateur station present and operating on the 
frequencies on which such emissions appear. The Commission sees no need 
to require an Access BPL operator to reduce emissions below the part 15 
limits where there is no potential for interference. In addition, it 
requires that a database of Access BPL systems be established to allow 
amateur operators to identify BPL operations in their area before the 
systems commence operation so that they have an opportunity to alert 
the BPL operator of their presence before the system is activated. The 
Commission addressed specific points in ARRL's arguments in paragraphs 
52 through 56 of this Second Report and Order.
    33. The Commission also noted that throughout this proceeding and 
as new equipment that allows BPL operators to better manage their 
frequency use at specific locations has become available, it observed 
BPL operators taking active steps to locate and avoid interference to 
amateur operators. Given that identification and resolution of harmful 
interference can involve expenditures of staff time and resources for 
Access BPL providers and possibly the temporary disruption of service 
to their subscribers, these providers have a strong incentive to take a 
priori steps to ensure that they avoid causing interference to the 
local radio services, including amateurs. Notwithstanding the 
occasional interference that was found by amateurs from the trial 
systems that were operated during the early phases of BPL development 
such as those examined in the staff presentations (and which, in some 
cases, were operating with emissions levels that were found to exceed 
the part 15 limits by amounts ranging from 1 to 4 dB), the Commission 
observed, as described by IBEC and CURRENT in their comments, that 
Access BPL operators are taking effective steps as contemplated in the 
BPL Order to avoid interference to amateur and other licensed services, 
including working with local amateur operators. Moreover, our own 
internal records on enforcement matters show only one complaint of 
interference from Access BPL to fixed licensed operations; that 
complaint was submitted recently and is under investigation at this 
time. In summary, the Commission sees no new information or reasoning 
in ARRL's submissions or other information regarding the three 
additional staff presentations in the preliminary materials released in 
July 2009 that would warrant changing the current rules and, 
specifically, it sees no need to further restrict the operations of BPL 
systems to protect licensed services.

Measurement Distance Extrapolation Issues

The Extrapolation Factor

    34. Overview. In the BPL Order, the Commission set forth guidelines 
for measurement of the emissions from Access BPL systems. These 
guidelines, inter alia, specify that emissions from Access BPL devices 
operating below 30 MHz are to be measured for compliance with the 
radiated emissions limits in Sec.  15.209 of the rules. Those limits 
are based on measurements made at 30-meters horizontal (lateral) 
distance from the device under test. However, for practical reasons 
associated with measurement in the field, the Access BPL measurement 
guidelines recommend that measurements should normally be performed at 
a horizontal separation distance of 10 meters from the overhead power 
line, and they also indicate that measurements can be performed at 3 
meters if necessary because of ambient emissions, safety or practical 
considerations. The field strength of radiated emissions does, however, 
decrease with increasing distance from the emitter due to propagation 
loss. Because of this attenuation with distance, the field strength of 
emissions from a device measured at the 3-meter or 10-meter distances 
specified in the guidelines will generally be higher than those 
measured at the 30-meter distance on which the emission standard is 
based. In order to apply the emissions standard consistently, the 
measurement results must be adjusted to account for distance 
attenuation when measurements are made at a distance other than 30 
meters.
    35. The Commission specified distance extrapolation factors to 
convert the BPL emissions measurements for frequencies below and above 
30 MHz to appropriate values for tests made at the 3-meter and 10-meter 
distances recommended in the BPL measurement guidelines. For BPL 
operations on frequencies below 30 MHz, the frequency range at issue 
here, some commenters in the initial phase of this proceeding, 
including ARRL, recommended the use of an extrapolation factor of 20 
dB/decade, while others recommended an extrapolation factor of 40 dB/
decade. The Commission concluded in the BPL Order that ``[g]iven the 
lack of conclusive experimental data pending large scale Access BPL 
deployments,'' it would ``continue the use of the existing part 15 
distance extrapolation factors'' specified in the rules, i.e., 40 dB/
decade for frequencies below 30 MHz and 20 dB/decade for frequencies at 
or above 30 MHz, but with the distance measured as the slant-range 
distance from the overhead power line to the center of the measurement 
antenna rather than horizontal (lateral) distance from the nearest 
point of the overhead power line carrying the BPL signals to the center 
of the measurement antenna, as illustrated in Figure 1 of Appendix C, 
of this Second Report and Order. This is the horizontal (lateral) 
distance between the center of the measurement antenna and the vertical 
projection of the overhead power line carrying the BPL signals down to 
the height of the measurement antenna when measurements are taken at a 
point that is perpendicular to the power lines. It further stated that 
``if new information became available that alternative emission limit/
distance standards or extrapolation factors would be more 
appropriate,'' it would revisit this issue at another time.
    36. ARRL filed a petition for reconsideration of the Commission's 
decision in the BPL Order to use 40 dB/decade as the extrapolation 
factor for frequencies below 30 MHz. In support of its argument that an 
extrapolation factor of 20 dB/decade should be used, ARRL also 
submitted, through ex parte

[[Page 71900]]

comments, reports on three studies conducted by the United Kingdom's 
Office of Communications (OFCOM) and a standard by the Special 
International Committee on Radio Interference (CISPR) regarding 
emission measurements for BPL systems and a proposal for a sliding 
scale extrapolation factor based on a 1996 CISPR standard. The first 
OFCOM study, ``OFCOM, Ascom PLT Measurements in Winchester (May 11, 
2005)'' (Winchester Study) reported measurements of an underground 
Access BPL trial system in Winchester, United Kingdom. In that study, 
OFCOM concluded that the electromagnetic field attenuates at a rate 
between 20 dB and 25 dB/decade at this BPL installation. The second 
OFCOM study, ``OFCOM, DS2 PLT Measurements in Crieff (May 11, 2005)'' 
(Crieff DS2 Study) reported measurements of an Access BPL trial system 
in Crieff, United Kingdom. That study concentrated only on the benefits 
of programmable notches in the equipment and did not provide any data 
on distance extrapolation. The third OFCOM study, ``OFCOM, Amperion PLT 
Measurements in Crieff (May 11, 2005)'' (Crieff Amperion Study) 
reported measurements of an overhead, pole-mounted Access BPL trial 
system, also in Crieff, United Kingdom. In the Crieff Amperion Study, 
OFCOM concluded that the emitted field attenuates at a rate of 28 dB/
decade.
    37. On reconsideration, the Commission found the OFCOM studies and 
the CISPR standard unpersuasive in that there was no ``new'' or 
convincing information not already known, and affirmed its decision to 
use the existing part 15 distance extrapolation factor of 40 dB/decade 
attenuation rate in the measurements of BPL emissions on frequencies 
below 30 MHz.
    38. In ARRL v. FCC, supra, the court found that the Commission did 
not offer a reasoned explanation for its dismissal of empirical data 
that was submitted ex parte by ARRL, i.e., the three OFCOM studies and 
additional ARRL analysis intended to suggest that an extrapolation 
factor of 20 dB/decade may be more appropriate for Access BPL. The 
court ordered the Commission either to ``provide a reasoned 
justification for retaining an extrapolation factor of 40 dB/decade for 
Access BPL systems sufficient to indicate that it has grappled with the 
2005 studies, or adopt another factor and provide a reasoned 
explanation for it.''
    39. The Commission acted to respond to the court's directive in the 
RFC/FNPRM. Therein, it provided a more detailed explanation of its 
reasons for selecting 40 dB/decade as the extrapolation factor for 
frequencies below 30 MHz and in particular why it does not believe that 
the studies and technical proposal submitted earlier by ARRL provide 
convincing information that it should use an extrapolation factor that 
is different from (and, specifically, less than) 40 dB/decade as 
required in the second element of the court's directive in ARRL v. FCC. 
In summary of that explanation, the Commission stated that:
    i. There were no significant studies that examined the very large 
number of measurements that would be needed to address the different 
site characteristics that affect the attenuation of emissions below 30 
MHz;
    ii. The studies submitted by ARRL in its 2005 ex parte provided 
only anecdotal information on two different types of installations 
(overhead and underground) from two single sites and also had certain 
methodological shortcomings; and
    iii. With respect to its proposal for a sliding scale extrapolation 
factor, ARRL did not provide an explanation as to how its formula was 
derived or how to use it to determine the extrapolation factor, nor did 
it provide a rationale for selecting such a formula or information as 
to the relationship between the performance of emissions from BPL 
technology and the specifications for reduction of power line noise 
adopted in the standard.
    40. In the RFC/FNPRM, the Commission also observed that since its 
adoption of the BPL Reconsideration Order, reports had become available 
on two new technical studies addressing attenuation of BPL emissions 
with distance, one by NTIA in October 2007 that described a second 
phase of its simulation study on the potential for interference from 
Access BPL systems (NTIA Phase 2 Study) and the other by the Federal 
Republic of Brazil (Brazil Study) in June 2008 that presented the 
results of a measurement study of BPL emissions. In addition, it noted 
that the IEEE working group on power line communications technology 
electromagnetic compatibility was working on a standard for EMC testing 
and measurements methodology for BPL equipment and installations (IEEE 
P1775/D2) that included a provision for determining extrapolation 
(distance correction) factors on a site-by-site basis using in situ 
measurements as part of its work on that standard.
    41. In view of these new studies and consistent with its stated 
intention in the BPL Order to revisit the extrapolation factor if new 
information became available and the opportunity provided by the 
Court's remand of the extrapolation factor, the Commission decided to 
conduct further rulemaking to review its decision on the extrapolation 
factor. It requested that interested parties submit additional comment 
and information on the BPL extrapolation factor and specifically asked 
that such comment and information address (1) The three studies and 
proposal for a sliding scale extrapolation factor submitted previously 
by ARRL as part of its ex parte filing of July 8, 2005 in this 
proceeding, (2) the NTIA Phase 2 and Brazil studies with respect to 
their findings on the extrapolation factor for BPL systems, and (3) the 
existing slant-range method as it pertains to the effective field 
attenuation rate in a horizontal distance context. The Commission 
further requested submission of any other new empirical studies or 
information that may provide information regarding the BPL distance 
attenuation extrapolation factor. The Commission stated that its goal 
in this review is to provide BPL measurement procedures that will 
adequately ensure compliance with the Section 15.209 emissions standard 
for emissions at or below 30 MHz without placing unfair or undue 
compliance burdens on equipment manufacturers and users. In conducting 
this review, the Commission indicated that initially it continued to 
believe the existing 40 dB/decade extrapolation factor, in conjunction 
with the slant-range distance method, was reasonable and appropriate 
for adjusting measurements of BPL emissions on frequencies below 30 
MHz.
    42. The Commission also recognized that there is considerable 
variability around the 40 dB/decade value at different sites. The 
result of this variability is that the actual attenuation at some sites 
could be less than 40 dB/decade and using the current extrapolation 
factor at such sites could produce an adjusted measurement that would 
be less than the level that would be measured at the standard 30-meter 
measurement distance specified in Sec.  15.209 of the Commission's 
rules. The Commission therefore requested comment on whether it would 
be desirable to modify the value of the BPL extrapolation factor to be 
30 dB/decade or some other value. It observed that extrapolated 
emission levels based on a 30 dB/decade extrapolation factor when 
applied to slant distance would be comparable to the extrapolated 
emission levels based on a 20 dB/decade extrapolation factor applied to 
horizontal (lateral) distance. Recognizing that reliance on a 30 dB/

[[Page 71901]]

decade extrapolation factor could increase the compliance burden for 
BPL equipment and systems that are tested at locations where the 
attenuation rate is in fact in the range of 40 dB/decade or greater, 
the Commission clarified that in all cases, measurements of Access BPL 
equipment and systems will be allowed to be made at the 30-meters 
distance specified in Sec.  15.209 of the Commission's rules and that 
where possible, the Commission's staff will make measurements at this 
distance when testing for compliance.
    43. After consideration of the most recent information and comments 
on this matter and further deliberation on all of the studies and 
information in the record, the Commission has decided to retain the 40 
dB/decade extrapolation factor for frequencies below 30 MHz. There are 
several reasons that lead us to this conclusion. Initially, the 
Commission observed that the 40 dB/decade extrapolation for frequencies 
below 30 MHz has served successfully in our program to control 
emissions from radio frequency devices for many years. It also observed 
that, while ARRL contends that 20 dB is the only scientifically correct 
and valid value for an extrapolation factor, the studies and 
information before us shows considerable differences in extrapolation 
factors under various powerline system configurations and usage 
conditions. The Commission concludes that there is no single 
``correct'' value for an extrapolation for RF emissions from power 
lines, and instead find that the compelling and reasonable solution is 
to use the existing part 15 extrapolation factor that both has a 
scientific basis and has stood the test of time for a wide variety of 
devices and systems. It also notes that, using the slant range method 
in performing measurements has the effect of reducing the extrapolation 
factor to approximately 20 dB. The Commission considers too, that the 
extrapolation factor used with BPL measurements is only one element in 
a comprehensive set of rules that are designed and intended to minimize 
the risk of harmful interference from BPL operations and to put in 
place appropriate measures to eliminate such interference if it should 
occur. In that context, the rules require that harmful interference be 
corrected under any circumstances. Measurements for examination of 
compliance are important, to be sure, but interference must be 
corrected even if measurements indicate that the BPL operations at the 
site are compliant. While ARRL asserts that an extrapolation factor 
that is too lax will lead to widespread instances of harmful 
interference that should be corrected ex ante as opposed to ex post, it 
has seen little evidence of harmful interference being caused under the 
rules as adopted with a 40-dB extrapolation factor.
    44. In addition, the Commission notes that there is no support from 
any of the commenting parties that modifying the extrapolation factor 
to 30 dB/decade in order to take a more conservative approach that 
would compensate for the variability in the attenuation rate would 
provide a more appropriate extrapolation factor. Therefore, it is not 
adopting that change. To provide clarity for those conducting 
measurements for compliance of Access BPL equipment and systems with 
Sec.  15.209 of the Commission's rules emissions standards, the 
Commission specifies the extrapolated values of compliant emissions 
levels at 3-meter and 10-meter horizontal (lateral) distance from the 
nearest point of the overhead power line carrying the BPL signals for 
typical heights of medium voltage power lines in the BPL measurement 
guidelines. The Commission is also adopting its proposal for a new 
method for determination of site specific extrapolation factors in 
measurements of emissions from BPL systems.
    45. Looking more closely at this issue, the Commission finds that 
ARRL has not provided convincing information that the value of the 
measurement distance extrapolation factor for Access BPL should be 
reduced from 40 dB/decade to 20 dB/decade or some other number close to 
that value. While ARRL offers detailed and lengthy submissions of 
information on propagation of RF energy below 30 MHz and critiques of 
the studies, analyses and information provided by others, including 
this Commission, that information does not provide any new insights on 
radio propagation that would alter our decision. Moreover, its 
arguments for a 40 dB/decade standard do not account for two key 
factors that affect the significant attenuation of RF energy in this 
region of the spectrum: Factors in the emissions process (such as 
ground effects and the presence of multiple power lines and their 
position on the pole) and the significant variability in attenuation 
rate across different installation sites.
    46. The Commission finds ARRL arguments to be unpersuasive. First, 
it is important to recognize that there is no ``FCC-laboratory 
recommendation'' as characterized by ARRL. The Commission is under no 
obligation to discuss in a rulemaking proceeding every staff 
observation or opinion provided during the course of internal 
deliberations. It observes that the 20 dB/decade extrapolation factor 
was part of one of three options presented on slide 19. The 
presentation offered no specific analysis or measurement data 
supporting this extrapolation factor. Rather, as specified on the 
slide, the authors offered it as a way to postpone and/or reduce the 
interference potential of BPL systems. Additionally, as noted by 
Arkados and HomePlug, none of the five FCC staff presentations actually 
examined the path loss extrapolation factor, but rather, they examined 
other technical issues such as the effect of the distance down the 
power line, differences in radiated field strength due to the detector 
that was employed, effect of measurement receiver antenna height, 
audible interference and antenna polarization. The Commission therefore 
did not (and still do not) consider that the information on which the 
provided option on slide 19 was based to be sufficient or 
compelling such that it should override or supersede other information 
that we also considered in the extrapolation factor decision. As UTC 
observes, the staff presentations merely included a 20 dB/decade 
extrapolation factor as one option among many for regulating BPL 
operations in the HF bands; the presentations did not find that a 20-dB 
extrapolation factor represented the actual rate of decay, nor did they 
contain any underlying information or analysis that would support such 
a finding. Further, with respect to ARRL's assertions regarding our use 
of new studies in the RFC/FNPRM as ex post facto evidence, it 
apparently overlooks our quite specific statement therein that the 
decision to adopt the 40 dB/decade standard was based on information 
available at the time of the decision, not newly available information.
    47. With regard to the new studies identified in the RFC/FNPRM, 
ARRL contends that the major flaw in the NTIA Phase 2 Study is that the 
modeling used does not fully account for the way that field strength 
decays at angles other than 90 degrees. ARRL further argues that with 
respect to height, the report errs in its attempted justification of 
the 5 dB height correction above 30 MHz but not below, and it justifies 
40 dB/decade by disregarding 20 percent of the data points. On the 
other hand, CURRENT quotes the NTIA Phase 2 Study as stating: ``[a]t or 
above 10 MHz, the simulation results show good agreement between the 
rate that field strength decays and the [40 dB/decade] distance 
extrapolation rate in the part 15 rules.''

[[Page 71902]]

HomePlug also agrees that the NTIA Phase 2 Study clearly demonstrates 
that the 40 dB/decade extrapolation factor is the correct value at or 
above 10 MHz, and much closer below 10 MHz than figures used in the 
studies submitted by ARRL. The Commission observes that NTIA's modeling 
in its Phase 2 Study indicates that the field along a complex power 
line model is highly varied, with areas of greater and lesser field 
strength produced by cancellation and reinforcement effects. However, 
there are some regularities, including field strength maxima at 
multiples of wavelengths along the power line, which is the reason why 
the Commission adopted the requirement for measurements at multiple 
points along the power lines in our BPL measurement guidelines. In 
addition, as discussed above, ARRL's own modeling shows that the 
magnetic field (measured below 30 MHz) does not vary greatly with 
height. Further, the Commission agrees with NTIA's position that ``the 
80th percentile values eliminate the localized peaks that are unlikely 
to be encountered by a radio receiver randomly located in close 
proximity to an Access BPL power line.'' Thus, the Commission finds 
that the NTIA Phase 2 Study is not flawed as argued by ARRL.
    48. The Commission recognizes the concerns of ARRL and IBEC 
regarding the Brazil Study. In addition, like the OFCOM studies before 
it, the Brazil Study would, in the best of circumstances provide only 
anecdotal information on the attenuation rate of BPL emissions as it 
only conducted measurements at a single location, rather than the very 
large number of sites that would be needed to develop a generalized 
description of that parameter. As it stated in the RFC/FNPRM, these 
studies do, however, provide an indication that BPL emissions tend to 
attenuate at rates that vary substantially across different sites, and 
that those rates can be much higher than the 20 dB/decade suggested by 
ARRL. In fact, the Brazil Study, while not individually probative, 
provides support for a much higher extrapolation factor than the 
similarly insubstantial OFCOM studies provided by ARRL.
    49. The Commission agrees with ARRL that emissions radiating 
upwards from overhead power lines are likely to attenuate at lower 
rates than emissions radiating horizontally and lower to the ground. In 
cases where an amateur antenna is located on a tower above the height 
of the power lines, as is typical of fixed amateur stations, we would 
expect that the level of any emissions received by that antenna might 
typically be higher than emissions received by a similar antenna 
located below the height of the power lines, all other things the same, 
because the path to the tower-mounted antenna will be less affected by 
the ground. However, the Commission's Access BPL rules provide for 
protection of such antennas by the absolute application of the 
prohibition against causing harmful interference in Sec.  15.5 of the 
rules. Also the Commission would generally expect that if a BPL 
installer sees a tower-mounted antenna, the installer would take steps 
to avoid interference to it before the system commences operation. In 
any case, for safety reasons, our rules provide for measurement of 
Access BPL systems from locations relatively close to the ground, where 
attenuation rates are likely to be higher, rather than at heights 
similar to power lines.
    50. ARRL argues a number of technical points to support using the 
free-space (or near free-space) 20 dB/decade attenuation rate 
associated with line sources. Again, the Commission agrees with ARRL on 
all of these technical points of well-documented RF propagation theory. 
While it did not explain earlier decisions on Access BPL at the level 
of detail that involved mentioning these factors (and do not believe 
that it is routinely necessary to explain propagation considerations 
which are a matter of accepted electromagnetic physics theory), the 
Commission did consider them in its decision. In fact, they were an 
intrinsic element of our deliberations. As a result, the Commission 
included provisions in the Access BPL measurement guidelines for 
testing along the power lines at specified intervals where emissions 
would be expected to be highest. It also considered that ground 
absorption and other environmental effects present near the surface 
that limit RF propagation typically result in attenuation of emissions 
in the MF and HF bands at rates much higher than the 20 dB/decade free 
space model, especially at the 1 meter height specified in the Access 
BPL measurement guidelines.
    51. ARRL contends it is illogical to conclude that, if a 20 dB/
decade extrapolation is appropriate at 30.001 MHz, the extrapolation 
somehow suddenly jumps to 40 dB/decade at 29.999 MHz. While ARRL is 
correct with regard to the physics of this issue, as CURRENT observes, 
``regulation is often a matter of drawing bright lines through gray 
lines.'' The Commission commonly uses ``bright line'' standards in its 
rules to provide clarity, simplicity, predictability and ease of 
applicability. The ``bright line'' difference in the extrapolation 
factors for under and over 30 MHz is intended to provide clear guidance 
in a region of the spectrum where there is considerable variability in 
the predictability of results. The Commission continues to believe that 
the current ``fixed line'' or ``bright-line'' approach for the 
different extrapolation factors above and below 30 MHz is appropriate 
for practical and administrative purposes.
    52. The arguments of ARRL and CURRENT concerning the technical 
validity of using 40 dB/decade as the extrapolation factor for 
measuring emissions on frequencies below 30 MHz demonstrate the 
complexity involved in describing and estimating field strengths in the 
near-field regions of emissions. ARRL is generally correct in its 
technical presentation of the theory of such fields, i.e., that 
emissions decay in the reactive near field at a rate of 40 dB/decade 
within a distance of [lambda]/2[pi] from the source and then in the 
radiating near field out to 2D\2\/[lambda] at a rate of 20 dB/decade. 
The very long lengths of typical power line segments therefore would 
not be expected to affect the decay rate of field strengths relative to 
reactive near field phenomena and therefore at distances greater than 
10 meters all frequencies above 4.78 MHz will generally be outside the 
reactive near field boundary. However, ARRL's description of the 
behavior of fields also shows that while the attenuation rate in the 
radiating near field is generally on the order of 20 dB/decade (in the 
free-space or near free-space case), there are standing wave patterns 
and other phenomena that make predictions unreliable. In addition, when 
measuring relatively close to the ground (at the 1-meter height 
specified for measurements at frequencies below 30 MHz), the proximity 
to and variation of ground features and other conditions cause great 
variability in signal levels. ARRL recognizes these ground effects, but 
argues that licensed services should not be protected only at ground 
level and that to do this the extrapolation factor should take into 
account the normally encountered antenna height of the victim receiver. 
Given that BPL measurements will be made close to the ground for the 
safety and practical reasons indicated and the propagation 
characteristics that are likely to be present in ground environments, 
the Commission continues to believe that there is justification for 
presuming that the expected attenuation rate of measured emissions at 
frequencies below 30 MHz is greater than 20 dB/decade. It also agrees 
with ARRL that licensed services should be protected in all cases and 
in this regard, the regime

[[Page 71903]]

of rules we have established for Access BPL systems, provides that 
protection.
    53. The Commission observes that none of the standards mentioned by 
ARRL apply to Access BPL equipment and the specific environments in 
which these devices operate. In particular, even though ARRL insists 
that the CISPR 18 standard does apply to BPL as it would apply to any 
source of RF noise, the Commission notes that CISPR has been working on 
the subject of an emission standard for BPL as far back as 2000 under 
CISPR Subcommittee G. The work to develop a standard specific to BPL 
has continued in CISPR Subcommittee I, however, this work has been 
recently reset to its preliminary stage due to the complex issues 
surrounding RF emissions at frequencies below 30 MHz, with signal 
attenuation being highly variable depending on the localized 
environment. Moreover, the Commission finds that the record in this 
proceeding has established a substantial body of information that 
supports the use of 40 dB/decade in conjunction with slant-range 
distance to adjust the emissions level for test results obtained in 
accordance with the measurement standards it adopted for Access BPL.
    54. In addition, as discussed in the RFC/FNPRM, the slant-range 
distance method in the Access BPL measurement guidelines works with the 
40 dB/decade factor to yield extrapolated emissions level values that 
have the effect of imposing a more conservative emissions standard than 
would be derived using the horizontal (lateral) distance from the 
nearest point of the overhead power line carrying the BPL signals. In 
this regard, at the relatively short distances at which Access BPL 
emissions are to be measured, i.e., distances 30 meters or less, 
applying the slant-range measurement method in the extrapolation of the 
measurements effectively reduces the compliant emission levels for BPL 
systems with respect to the horizontal distance from the power line. 
This reduction results because at any given horizontal distance from 
the power line, the slant-range distance is longer than the horizontal 
distance. The relationship is one of basic plane geometry that occurs 
due to the height of the power line on which the BPL signal injector is 
installed. When extrapolated values at 40 dB per decade of slant-range 
distance are plotted against the horizontal distance, the effective 
extrapolated emission level curve more closely follows the emission 
level curve based on a 20 dB per decade extrapolation factor at 
horizontal distances than the emission level curve based on a 40 dB per 
decade extrapolation factor at horizontal distances. NTIA's modeling 
results in its Phase 2 Study effectively reflect this observation. 
Also, given that the Access BPL measurement guidelines require 
compliance measurements to be taken at 30 meters or less, the effect of 
the slant-range distance provision is significant at all distances 
where the extrapolation factor can be used.
    55. ARRL and several of the commenting parties addressed the 
Commission's request for comment on whether it would be desirable to 
modify the extrapolation factor to be 30 dB/decade or some other value 
to account for the considerable variability around the 40 dB/decade 
expected attenuation value at different sites. It was our intent that 
this lower value would apply a more conservative approach that would 
compensate for those cases where the actual attenuation is less than 40 
dB. In opposing this plan, ARRL asserts that the Commission is not 
apparently convinced by its own ex post argument justifying use of 40 
dB/decade, as it immediately thereafter abandoned that argument and 
proposed instead to adopt an equally unjustified 30 dB/decade 
extrapolation factor in what appears to be the ``King Solomon'' 
approach rather than a real scientific analysis. ARRL rejects the 
approach underlying the 30 dB/decade proposal and argues that the 
Commission is obligated to adopt a scientifically valid extrapolation 
standard, which it contends is 20 dB/decade. The UTC and CURRENT also 
oppose such a change, stating that the Commission was correct to select 
40 dB/decade as the distance extrapolation and that it should maintain 
that value. UPLC argues that a 30 dB/decade value would be 
inappropriate and that a reduced value would impose a significant 
compliance burden on Access BPL systems. CURRENT argues that the 
Commission's original selection of 40 dB/decade is well supported by 
the record and that the mere possibility of other supportable 
conclusions, especially if based on other studies, does not warrant a 
change. CURRENT and the UTC further submit that the now-demonstrable 
lack of interference reports from CURRENT's extensive operations 
supports not changing the extrapolation standard.
    56. It is plain from the record that reducing the extrapolation 
factor to the more conservative 30 dB/decade level to compensate for 
those situations in which the actual attenuation is less than 40 dB/
decade would not satisfy the concerns of any of the parties to this 
matter or otherwise provide any benefits that would improve our Access 
BPL measurement guidelines. Contrary to ARRL's misapprehension, our 
consideration of a reduction in the extrapolation factor was not 
intended as a ``compromise'' approach in consideration of the wide 
variations in the studies and data before us. Rather, it was a 
recognition of the uncertainty or inexactness inherent in the 
information available and the amount of analysis undertaken at the 
time, and a signal of our openness in reconsidering the issue in that 
light.
    57. Taking into consideration the above evaluations and all of the 
additional information before us now, the Commission believes that the 
most compelling path points to retaining the 40 dB extrapolation 
factor. In this regard, it first observed that it used this 
extrapolation value successfully with measurements at frequencies below 
30 MHz in its program to control emissions from radio frequency devices 
for many years. This includes not only consumer products, but also 
industrial, scientific and medical equipment that may use thousands of 
watts of power and couple radio noise onto power lines that can radiate 
for significant distances. In addition, while ARRL asserts that there 
is only one scientifically correct and valid answer of an extrapolation 
factor of 20 dB, the studies and information before us show 
considerable differences in extrapolation factors under various system 
configurations and usage condition. The Commission concludes that there 
is no single ``right'' value for the extrapolation factor that 
accurately reflects environmental conditions in all cases, and instead 
finds that the most appropriate decision is to use the existing value 
in the rules that both has a scientific basis and has stood the test of 
time for a wide variety of devices and systems. The Commission also 
considers that, as observed in the discussions, using the slant range 
to perform measurements has the effect of reducing the extrapolation 
factor to approximately 20 dB. In addition, the attenuation factors 
that are typically present when making measurements close to the 
ground, as specified in the BPL rules, tend to increase the signal loss 
above that which occurs from the spreading of energy in free space 
propagation. Finally, while one can debate the propriety and scientific 
validity of any particular extrapolation factor, the Commission must 
consider that the extrapolation factor is but one element in the 
context of an overall set of rules that are designed to minimize the 
risk of harmful interference and to put in place appropriate measures 
to eliminate such interference if it should occur. Whether the 
extrapolation factor

[[Page 71904]]

is 20 dB or 40 dB or somewhere in between is far less important than 
the fact that harmful interference must be corrected under any 
circumstances. While ARRL asserts that an extrapolation factor that is 
too lax will lead to widespread instances of harmful interference that 
should be corrected ex ante as opposed to ex post, the Commission has 
seen little evidence of harmful interference being caused. Accordingly, 
the Commission will not modify the extrapolation factor for the 
emissions standard for frequencies below 30 MHz to compensate for the 
variability in the field strength attenuation rate at different 
locations.
    58. The Commission also reiterates here the clarification it issued 
in the RFC/FNPRM that measurements of BPL equipment and systems should 
be made at the 30-meters distance specified in Sec.  15.209 of the 
Commission's rules unless circumstances such as high ambient noise 
levels or geographic limitations are present, in which case, a 3-meter 
or 10-meter horizontal distances indicated in the BPL measurement 
guidelines may be used. The Commission further clarifies that 
measurements made at the 30-meter distance specified in the Sec.  
15.209 of the Commission's rules emissions standard will prevail over 
measurements made at shorter distances and that where possible and 
practical, the Commission's staff will make measurements at this 
distance when testing for compliance. As indicated, to provide 
additional clarity in our compliance requirements, the Commission also 
amended the BPL measurement guidelines to specify the extrapolated 
values of the emissions level for compliance at 3-meter and 10-meter 
horizontal distances from the nearest point of the overhead power line 
carrying the BPL signals for typical heights of medium voltage power 
lines. These clarifications of the existing rules as well as the 
adoption of the definition for slant-range distance would assist the 
industry in ensuring compliance of BPL systems without imposing 
additional regulatory costs.

Site-Specific Extrapolation Factors

    59. In the RFC/FNPRM, the Commission proposed to allow parties 
testing BPL systems for compliance with the radiated emissions limits 
to determine distance correction factors on a site-by-site basis using 
a new in situ measurement procedure designed specifically for Access 
BPL. This plan, which was based on a concept under consideration in the 
IEEE Working Group P1775/D2 effort at that time and which has been 
finalized since, would allow entities conducting measurements of Access 
BPL systems and equipment to determine an extrapolation factor specific 
to a site by fitting a straight line to measurements of field strength 
in dB[micro]V/m vs. logarithmic distance in meters from the nearest 
conductor carrying BPL emissions, where the extrapolation factor would 
be taken as the slope of that line. The Commission indicated that the 
site-specific extrapolation factor would be an alternative to the 
extrapolation factor specified in the BPL measurement guidelines and 
would be replacing the existing method using only two data points for 
determining site-specific extrapolation factors currently in the rules. 
The proposed alternative method would only be applicable to Access BPL 
devices operating on frequencies below 30 MHz.
    60. Under the proposal in the RFC/FNPRM, entities conducting 
measurements would determine an extrapolation factor specific to the 
site by fitting a straight line to measurements of field strength in 
dB[micro]V/m vs. logarithmic distance in meters from the nearest 
conductor carrying BPL emissions, where the extrapolation factor would 
be taken as ten times the slope, n, of that line. The slope n any point 
on the straight line in [micro]V/m would be:

(20logEr-20logE2)/(10logD2-
10logDr)

where Er is the measured field strength at distance 
Dr

    The field strength in dB[mu]V/m at any distance D along the best 
straight line fit is estimated from the value of n as:

20logEr = 20logE2 + n(10logD2 -
10logDr)

    The extrapolation factor would be derived from a best straight line 
fit determined by a linear least squares regression calculation from 
measurements made at four or more lateral distances from the overhead 
line, starting at no less than 6 meters from the lateral plane and 
spaced from each other by at least 3 meters. If these measurements 
allow a straight line with a negative slope to be calculated or drawn 
with reasonable fit (the minimum regression coefficient of multiple 
correlation would be 0.9), the best straight line fit would be used to 
calculate field strength at the 30-meters standard measurement distance 
in the rules according to the equation above. If the four measurements 
do not fall near any straight line or negative slope, measurements at a 
new distance would be added until a reasonable fit to a straight line 
is indicated. In addition, measurements that obviously show a ``null'' 
or other ``outlier'' value would be ignored. Parties employing site-
specific extrapolation values would be required to provide a record of 
the measurements under the above procedure and to submit those 
measurements and their derivation of the in situ values with any 
measurements with compliance submissions to the Commission.
    61. The Commission continues to believe the availability of a site-
specific approach for determining values for extrapolation of 
measurements of Access BPL emissions on frequencies below 30 MHz is a 
desirable and useful alternative to the fixed extrapolation factor. The 
option to use site-specific values can substantially alleviate the 
measurement concerns associated with the standard extrapolation factor 
and the variability in attenuation rates that may be observed in the 
field, and particularly where measurements at a site may plainly not 
appear to conform to the 40 dB/decade standard. It also recognizes 
ARRL's concerns that a site-specific option could be abused by careful 
selection of measurement points. However, the Commission finds that the 
proposed approach that requires four measurements spaced at least 3 
meters apart with provisions for additional measurements where a 
straight line with a negative slope is not approximated by the four 
initial measurements, is sufficient to develop a reliable indication of 
the attenuation rate at a site. In particular, it believes the 
requirement in this new procedure that the measurements used to develop 
the extrapolation value approximate a straight line with a negative 
slope as determined through the linear least squares regression method 
(with a minimum regression coefficient of multiple correlation of 0.9) 
will adequately guard against the ``cherry picking'' concern mentioned 
by ARRL. Where such a line cannot be approximated, the Commission will 
also require that measurements be made at a different perpendicular 
position along the power line very nearby or at the same perpendicular 
position but on the opposite side of the line from the first set of 
measurements.
    62. This new site-specific procedure will replace the existing 
Sec.  15.31(f)(2) of the Commission's rules alternative for Access BPL 
that only requires two measurements. This plan conforms substantially 
to the IEEE P1775-2010 standard which has been developed. The 
Commission observes that a straight line best fit of multiple data 
points using the least squares regression technique is not a new idea 
developed by the IEEE standard, it is a well-established and commonly 
used

[[Page 71905]]

statistical method. It notes that in the RFC/FNPRM, it proposed to 
derive the extrapolation factor from a best straight line fit 
determined by a linear least squares regression calculation from 
measurements made at four or more lateral distances from the overhead 
line, starting at no less than 6 meters from the lateral plane and 
spaced from each other by at least 3 meters; at that time, the IEEE 
standard was in a state of transition and we were merely proposing a 
measurement concept. The Commission now observes the IEEE P1775-2010 
has finalized its standard to specify that measurements be made at four 
or more lateral distances from the overhead line, starting at no less 
than 3 meters from the lateral plane and spaced from each other by at 
least 3 meters. The Commission adopted the distances as specified in 
the IEEE published standard for the new site-specific measurement 
procedure. This procedure is an improvement over the current procedure 
for determining site-specific extrapolation factors in Sec.  
15.31(f)(2) of the Commission's rules, which requires only two 
measurement points without any specific separation distance. The 
Commission cautions parties responsible for certification measurements 
to bear in mind that the objective of the site-specific procedure is to 
plot enough data points to draw a valid extrapolation curve; 
accordingly, in some situations the number of measurement points may 
need to exceed the recommended minimum for the resulting extrapolation 
to be valid. Further, as stated in the BPL Order and the BPL 
Reconsideration Order, operators of Access BPL systems are responsible 
for eliminating any harmful interference that may occur or must cease 
operation upon notification by a Commission representative that the 
device is causing harmful interference. Accordingly, the Commission 
amended its rules as set forth in Appendix C of this Order to establish 
a new method for determining site-specific extrapolation values for 
Access BPL measurements as described herein. Because this is an 
alternative method intended to facilitate compliance measurements which 
may be used at the BPL operator's discretion, the requirement provides 
benefits without imposing additional regulatory costs. The benefits of 
having this additional method would enable BPL operators to better 
adjust the operating parameters of BPL devices according to specific 
installation sites that might not conform to the standard extrapolation 
value, which could lead to cost savings and reduced interference 
potential. Additional provisions of this procedure are set forth in the 
revised Access BPL measurement guidelines in Appendix D of the Order.
    63. The Commission will not allow the site-specific procedure to be 
used at locations within 30 meters of a power pole with a ground 
conductor where the Access BPL signals devices are carried on a 
neutral/grounded line of the power system. In this regard, it is 
concerned that emissions from a grounding conductor mounted on the side 
of a power line pole could combine with the emissions from the overhead 
neutral power line to produce false indications of the attenuation rate 
that would distort the slope of the extrapolation curve. Accordingly, 
the Commission amended its rules as set forth in Appendix C to 
establish a new method for determining site-specific extrapolation 
values for Access BPL measurements as described herein. Additional 
provisions of this procedure are set forth in the revised Access BPL 
measurement guidelines in Appendix D of the Order.

The Access BPL Database

    64. ARRL contends that the BPL database is virtually useless due to 
errors, omissions and listings of systems that are not operating any 
longer and systems that have never been placed in operation. It cites 
as an example an incident in which it sent an email message to the 
person listed in the database for the Manassas, VA, BPL system, it 
found the email contact was invalid and follow-up email messages to the 
City of Manassas went unanswered. In its reply comments, the City of 
Manassas submits that when the system operator, Comtek, transferred 
operation of the system to the city, the contact was not updated 
immediately but the error was corrected promptly in April 2009 when the 
city was notified by ARRL that the listing was incorrect. The 
Commission agrees with ARRL that the database should be maintained with 
accurate, up-to-date information. The Commission's staff contacted the 
database manager, UTC, about ARRL's concerns and in its reply comments, 
UTC affirms that the database has been and is being reviewed 
periodically to ensure that the information is currently accurate. The 
Commission does note that while it is important that the database be 
up-to-date in all respects, it is most important that operating and 
soon-to-be operating systems not be omitted and it does not have 
information that such systems were not or are not listed. The 
Commission therefore encourages UTC to continue to be diligent in its 
management of the database and other interested parties to work with 
UTC in providing information to ensure that the records in the database 
are accurate and up-to-date.

Final Regulatory Flexibility Analysis

    65. As required by the Regulatory Flexibility Act (RFA),\1\ an 
Initial Regulatory Flexibility Analysis (IRFA) was incorporated in the 
Request for Comment and Further Notice of Proposed Rulemaking (RFC/
FNPRM) in ET Docket Nos. 04-37 and 03-104.\2\ The Commission sought 
written public comment on the proposals in the RFC/FNPRM, including 
comment on the IRFA. This present Final Regulatory Flexibility Analysis 
(FRFA) conforms to the RFA.
---------------------------------------------------------------------------

    \1\ See 5 U.S.C. 603. The RFA, see 5 U.S.C. 601-612, has been 
amended by the Small Business Regulatory Enforcement Fairness Act of 
1996 (SBREFA), Public Law 104-121, Title II, 110 Stat. 857 (1996), 
and the Small Business Jobs Act of 2010, Public Law 111-240, 124 
Stat. 2504 (2010).
    \2\ Request for Further Comment and Further Notice of Proposed 
Rulemaking in ET Dockets No. 04-37 and 03-104 (Amendment of Part 15 
Regarding New Requirements and Measurement Guidelines for Access 
Broadband Over Power Line Systems, Carrier Current Systems), 24 FCC 
Rcd 9669 (2009) (RFC/FNPRM).
---------------------------------------------------------------------------

A. Need for, and Objectives of, the Second Report and Order

    66. The Second Report and Order maintains the existing Access BPL 
emissions standards and other technical operation rules, as well as the 
existing extrapolation 40 dB/decade factor prescribed in the rules for 
use in measurement of emissions from Access BPL systems. In addition, 
the Second Report and Order modifies the rules to (1) Require a deeper 
notch filter depth when a notch filter is used to avoid interference to 
a specific frequency band; (2) adopt a definition for the slant-range 
distance used in the BPL measurement guidelines to further clarify its 
application; and (3) establish a new procedure for determining site-
specific extrapolation factors.
    67. The decisions in the Second Report and Order are consistent 
with the mandate by the United States Court of Appeals for the District 
of Columbia in ARRL v. FCC, and will provide regulatory certainty for 
both manufacturers of Access BPL equipment and systems operators so 
that development of equipment and construction of facilities can 
proceed unimpeded by any concerns about the status of the regulations 
with which equipment and systems must comply.\3\
---------------------------------------------------------------------------

    \3\ See American Radio Relay League, Incorporated, v. Federal 
Communications Commission (ARRL v. FCC), 524 F.3d 227 (D.C. Cir. 
2008).

---------------------------------------------------------------------------

[[Page 71906]]

B. Statement of Significant Issues Raised by Public Comments in 
Response to the IRFA

    68. There were no public comments filed that specifically addressed 
the rules and policies proposed in the IRFA.

C. Response to Comments by the Chief Counsel for Advocacy of the Small 
Business Administration

    69. Pursuant to the Small Business Jobs Act of 2010, the Commission 
is required to respond to any comments filed by the Chief Counsel for 
Advocacy of the Small Business Administration, and to provide a 
detailed statement of any change made to the proposed rules as a result 
of those comments. The Chief Counsel did not file any comments in 
response to the proposed rules in this proceeding.

D. Description and Estimate of the Number of Small Entities to Which 
the Rules Will Apply

    70. The RFA directs agencies to provide a description of, and, 
where feasible, an estimate of the number of small entities that may be 
affected by the proposed rules, if adopted.\4\ The RFA defines the term 
``small entity'' as having the same meaning as the terms ``small 
business,'' ``small organization,'' and ``small business concern'' 
under Section 3 of the Small Business Act.\5\ Under the Small Business 
Act, a ``small business concern'' is one that: (1) Is independently 
owned and operated; (2) is not dominant in its field of operations; and 
(3) meets may additional criteria established by the Small Business 
Administration (SBA).\6\
---------------------------------------------------------------------------

    \4\ See 5 U.S.C. 603(b)(3).
    \5\ Id. 601(3).
    \6\ Id. 632.
---------------------------------------------------------------------------

    71. Nationwide, there are a total of approximately 27.5 million 
small businesses, according to the SBA.\7\ A ``small organization'' is 
generally ``any not-for-profit enterprise which is independently owned 
and operated and is not dominant in its field.'' \8\ Nationwide, as of 
2002, there were approximately 1.6 million small organizations.\9\ The 
term ``small governmental jurisdiction'' is defined generally as 
``governments of cities, towns, townships, villages, school districts, 
or special districts, with a population of less than fifty thousand.'' 
\10\ Census Bureau data for 2002 indicate that there were 87,525 local 
governmental jurisdictions in the United States.\11\ We estimate that, 
of this total, 84,377 entities were ``small governmental 
jurisdictions.'' \12\ Thus, we estimate that most governmental 
jurisdictions are small.
---------------------------------------------------------------------------

    \7\ See SBA, Office of Advocacy, ``Frequently Asked Questions,'' 
http://www.sba.gov/advo/stats/sbfaq.pdf (accessed Dec. 2010).
    \8\ 5 U.S.C. 601(4).
    \9\ Independent Sector, The New Nonprofit Almanac & Desk 
Reference (2002).
    \10\ 5 U.S.C. 601(5).
    \11\ U.S. Census Bureau, Statistical Abstract of the United 
States: 2006, Section 8, page 272, Table 415.
    \12\ We assume that the villages, school districts, and special 
districts are small, and total 48,558. See U.S. Census Bureau, 
Statistical Abstract of the United States: 2006, section 8, page 
273, Table 417. For 2002, Census Bureau data indicate that the total 
number of county, municipal, and township governments nationwide was 
38,967, of which 35,819 were small. Id.
---------------------------------------------------------------------------

    72. The adopted rules pertain to manufacturers of unlicensed 
communications devices. The appropriate small business size standard is 
that which the SBA has established for radio and television 
broadcasting and wireless communications equipment manufacturing. The 
Census Bureau defines this category as follows: ``This industry 
comprises establishments primarily engaged in manufacturing radio and 
television broadcast and wireless communications equipment. Examples of 
products made by these establishments are: Transmitting and receiving 
antennas, cable television equipment, GPS equipment, pagers, cellular 
phones, mobile communications equipment, and radio and television 
studio and broadcasting equipment.'' \13\ The SBA has developed a small 
business size standard for firms in this category, which is: All such 
firms having 750 or fewer employees.\14\ According to Census Bureau 
data for 2007, there were a total of 939 establishments in this 
category that operated for part or all of the entire year. Of this 
total, 784 had less than 500 employees and 155 had more than 100 
employees.\15\ Thus, under this size standard, the majority of firms 
can be considered small.
---------------------------------------------------------------------------

    \13\ U.S. Census Bureau, 2007 NAICS Definitions, ``334220 Radio 
and Television Broadcasting and Wireless Communications Equipment 
Manufacturing''; http://www.census.gov/naics/2007/def/ND334220.HTM#N334220.
    \14\ 13 CFR 121.201, NAICS code 334220.
    \15\ http://factfinder.census.gov/servlet/IBQTable?_bm=y&-fds_name=EC0700A1&-geo_id=&-_skip=300&-ds_name=EC0731SG2&-_lang=en.
---------------------------------------------------------------------------

E. Description of Projected Reporting, Recordkeeping and Other 
Compliance Requirements

    73. The Second Report and Order does not contain new or modified 
information collection requirements. The minor modified technical 
requirements adopted in this Second Report and Order, as discussed 
below, do not impose significant burden and will not have a significant 
economic impact on a substantial number of small entities that are, or 
may be, subject to the requirements of the rules in the item.

F. Steps taken To Minimize Significant Economic Impact on Small 
Entities and Significant Alternatives Considered

    74. The RFA requires an agency to describe any significant 
alternatives that it has considered in reaching its proposed approach, 
which may include the following four alternatives (among others): (1) 
The establishment of differing compliance or reporting requirements or 
timetables that take into account the resources available to small 
entities; (2) the clarification, consolidation, or simplification of 
compliance or reporting requirements under the rule for small entities; 
(3) the use of performance, rather than design, standards; and (4) an 
exemption from coverage of the rule, or any part thereof, for small 
entities.
    75. In this Second Report and Order, we modify our rules and 
measurement procedures for Access BPL devices operating below 30 MHz to 
(1) Require a deeper notch filter depth when a notch filter is used to 
avoid interference to a specific frequency band; (2) establish a new 
procedure for determining site-specific extrapolation factors; and (3) 
adopt a definition for the slant-range distance used in the BPL 
measurement guidelines to further clarify its application. In reviewing 
the requirement for a 20-dB notching capability and current 
developments in BPL equipment, we now find that it would be appropriate 
to increase the required notching capability of Access BPL systems 
operating below 30 MHz to 25 dB from the existing requirement of 20 dB, 
when a notch filter is used to avoid interference to a specific 
frequency band. This deeper notching capability is technologically 
available and voluntarily implemented in the field by Access BPL 
operators to avoid potential interference to amateur radio operators; 
therefore, the new requirement would not pose a substantial burden on 
Access BPL manufacturers. To afford manufacturers time to redesign 
their equipment to comply with the new, more conservative 25-dB 
notching requirement, we are allowing an 18-month period from the date 
this action is published in the Federal Register before the requirement 
becomes effective.
    76. The Commission further established an alternative method to 
allow parties testing BPL systems for compliance with the radiated 
emissions limits to determine distance correction

[[Page 71907]]

factors on a site-by-site basis using an in situ measurement procedure 
when measurements cannot be made at the reference measurement distance 
of 30 meters as specified in the rules. Because this is an alternative 
method intended to facilitate compliance measurements which may be used 
at the BPL operator's discretion, the requirement provides benefits 
without imposing additional regulatory costs. The benefits of having 
this additional method would enable BPL operators to better adjust the 
operating parameters of BPL devices according to specific installation 
sites that might not conform to the standard extrapolation value, which 
could lead to cost savings and reduced interference potential.
    77. In addition, the Commission clarify that parties testing BPL 
equipment and systems for compliance with emissions limits in our rules 
should measure at the standard reference 30-meter distance whenever 
possible, and only measure at the shorter distances recommended in the 
BPL measurement guidelines if safety or ambient conditions require 
taking measurements at a closer distance such as 10 meters or 3 meters 
from the overhead line. The Commission also adopts a definition for the 
slant-range distance used in the BPL measurement guidelines to further 
clarify its application. The Commission also modified its BPL 
measurement guidelines to provide clarity for those conducting 
measurements for compliance of Access BPL equipment and systems with 
the Sec.  15.209 of the Commission's rules emissions standards by 
specifying the extrapolated values of compliant emissions levels at 3-
meter and 10-meter horizontal (lateral) distance from the nearest point 
of the overhead power line carrying the BPL signals, for typical 
heights of medium voltage power lines. These clarifications of the 
existing rules as well as the adoption of the definition for slant-
range distance would assist the industry in ensuring compliance of BPL 
systems, promoting possible cost savings without imposing additional 
regulatory costs.

Report to Congress

    78. The Commission will send a copy of the Second Report and Order, 
including this FRFA, in a report to be sent to Congress pursuant to the 
Congressional Review Act.\16\ In addition, the Commission will send a 
copy of the Second Report and Order, including this FRFA, to the Chief 
Counsel for Advocacy of the SBA.\17\
---------------------------------------------------------------------------

    \16\ See 5 U.S.C. 801(a)(1)(A).
    \17\ See 5 U.S.C. 604(b).
---------------------------------------------------------------------------

    79. Congressional Review Act. The Commission will send a copy of 
this Second Report and Order in a report to be sent to Congress and the 
Government Accountability Office pursuant to the Congressional Review 
Act, see 5 U.S.C. 801(a)(1)(A).

Ordering Clauses

    80. Pursuant to the authority contained in sections 4(i), 301, 302, 
303(e), 303(f) and 303(r) of the Communications Act of 1934, as 
amended, 47 U.S.C. 154(i), 301, 302, 303(e), 303(f) and 303(r), this 
Second Report and Order is hereby Adopted and part 15 of the 
Commission's Rules Are Amended as set forth in Final Rules effective 
December 21, 2011.

List of Subjects in 47 CFR Part 15

    Communications equipment, Radio.


Federal Communications Commission.
Marlene H. Dortch,
Secretary.

Final Rules

    For the reasons discussed in the preamble, the Federal 
Communications Commission amends 47 CFR part 15 to read as follows:

PART 15--RADIO FREQUENCY DEVICES

0
1. 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
2. Section 15.3 is amended by adding paragraph (hh) to read as follows:


Sec.  15.3  Definitions.

* * * * *
    (hh) Slant-Range Distance. Diagonal distance measured from the 
center of the measurement antenna to the nearest point of the overhead 
power line carrying the Access BPL signal being measured. This distance 
is equal to the hypotenuse of the right triangle as calculated in the 
formula below. The slant-range distance shall be calculated as follows:
[GRAPHIC] [TIFF OMITTED] TR21NO11.002

Where:

dslant is the slant-range distance, in meters (see Figure 
1, below);
dh is the horizontal (lateral) distance between the 
center of the measurement antenna and the vertical projection of the 
overhead power line carrying the BPL signals down to the height of 
the measurement antenna, in meters;
hpwr--line is the height of the power line, in meters; 
and
hant is the measurement antenna height, in meters.

[[Page 71908]]

[GRAPHIC] [TIFF OMITTED] TR21NO11.003

Dslant is the slant-range distance, in meters;
Dh is the horizontal (lateral) distance between the 
center of the measurement antenna and the vertical projection of the 
overhead power line carrying the BPL signals down to the height of 
the measurement antenna, in meters;
Dlimit is the distance at which the emission limit is 
specified in Part 15 (e.g., 30 meters for frequencies below 30 MHz);
Hpwr--line is the height of the power line, in meters; 
and
Hant is the measurement antenna height, in meters.


0
3. Section 15.31 is amended by adding a sentence at the end of 
paragraph (f)(2), by redesignating paragraphs (f)(3) through (f)(5) as 
(f)(4) through (f)(6), and by adding a new paragraph (f)(3) to read as 
follows:


Sec.  15.31  Measurement standards.

* * * * *
    (f) * * *
    (2) * * * This paragraph (f) shall not apply to Access BPL devices 
operating below 30 MHz.
    (3) For Access BPL devices operating below 30 MHz, measurements 
shall be performed at the 30-meter reference distance specified in the 
regulations whenever possible. Measurements may be performed at a 
distance closer than that specified in the regulations if circumstances 
such as high ambient noise levels or geographic limitations are 
present. When performing measurements at a distance which is closer 
than specified, the field strength results shall be extrapolated to the 
specified distance by using the square of an inverse linear distance 
extrapolation factor (i.e., 40 dB/decade) in conjunction with the 
slant-range distance defined in Sec.  15.3(hh) of this part. As an 
alternative, a site-specific extrapolation factor derived from a 
straight line best fit of measurements of field strength in dB[mu]V/m 
vs. logarithmic distance in meters for each carrier frequency, as 
determined by a linear least squares regression calculation from 
measurements for at least four distances from the power line, may be 
used. Compliance measurements for Access BPL and the use of site-
specific extrapolation factors shall be made in accordance with the 
Measurement Guidelines for Access BPL systems specified by the 
Commission. Site-specific determination of the distance extrapolation 
factor shall not be used at locations where a ground conductor is 
present within 30 meters if the Access BPL signals are on the neutral/
grounded line of a power system.
* * * * *

0
4. Section 15.37 is amended by adding paragraph (o) to read as follows:


Sec.  15.37  Transition provisions for compliance with the rules.

* * * * *
    (o) All Access BPL devices operating below 30 MHz that are 
manufactured, imported, marketed or installed on or after May 21, 2013 
shall comply with the requirements specified in Sec.  15.611(c)(1)(i) 
of this part.
0
5. Section 15.611 is amended by revising paragraph (c)(1)(i) to read as 
follows:


Sec.  15.611  General technical requirements.

* * * * *
    (c) * * *
    (1) * * *
    (i) For frequencies below 30 MHz, when a notch filter is used to 
avoid interference to a specific frequency band, the Access BPL system 
shall be capable of attenuating emissions within that band to a level 
at least 25 dB below the applicable Part 15 limits.
* * * * *
[FR Doc. 2011-30045 Filed 11-18-11; 8:45 am]
BILLING CODE 6712-01-P