Commission Seeks Comment on Shared Commercial Operations in the 3550-3700 MHz Band, 34119-34126 [2015-14495]

Agencies

• FEDERAL COMMUNICATIONS COMMISSION

[Federal Register Volume 80, Number 114 (Monday, June 15, 2015)]
[Proposed Rules]
[Pages 34119-34126]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2015-14495]


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FEDERAL COMMUNICATIONS COMMISSION

47 CFR Parts 1, 2, 90, 95, and 96

[GN Docket No. 12-354; FCC 15-47]


Commission Seeks Comment on Shared Commercial Operations in the 
3550-3700 MHz Band

AGENCY: Federal Communications Commission.

ACTION: Proposed rule.

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SUMMARY: In this document, the Commission seeks comment on three 
specific issues related to the establishment of a new Citizens 
Broadband Radio Service in the 3550-3700 MHz band (3.5 GHz Band). These 
issues are: Defining ``use'' of Priority Access License frequencies; 
implementing secondary markets in Priority Access Licenses; and 
optimizing protections for Fixed Satellite Services.

DATES: Submit comments on or before July 15, 2015 and reply comments on 
or before August 14, 2015.

ADDRESSES: You may submit comments, identified by GN Docket No. 12-354, 
by any of the following methods:
     Federal Communications Commission's Web site: https://fjallfoss.fcc.gov/ecfs2/. Follow the instructions for submitting 
comments.
     Mail: All hand-delivered or messenger-delivered paper 
filings for the Commission's Secretary must be delivered to FCC 
Headquarters at 445 12th St. SW., Room TW-A325, Washington, DC 20554. 
The filing hours are 8:00 a.m. to 7:00 p.m. All hand deliveries must be 
held together with rubber bands or fasteners. Any envelopes and boxes 
must be disposed of before entering the building. Commercial overnight 
mail (other than U.S. Postal Service Express Mail and Priority Mail) 
must be sent to 9300 East Hampton Drive, Capitol Heights, MD 20743. 
U.S. Postal Service first-class, Express, and Priority mail must be 
addressed to 445 12th Street SW., Washington DC 20554.
     People with Disabilities: Contact the FCC to request 
reasonable accommodations (accessible format documents, sign language 
interpreters, CART, etc.) by email: FCC504@fcc.gov or phone: 202-418-
0530 or TTY: 202-418-0432.
    For detailed instructions for submitting comments and additional 
information on the rulemaking process, see the SUPPLEMENTARY 
INFORMATION section of this document.

FOR FURTHER INFORMATION CONTACT: Paul Powell, Attorney Advisor, 
Wireless Bureau--Mobility Division at (202) 418-1613 or 
Paul.Powell@fcc.gov.

SUPPLEMENTARY INFORMATION: This is a summary of the Commission's Second 
Further Notice of Proposed Rulemaking in GN Docket No. 12-354, FCC 15-
47, adopted on April 17, 2015 and released April 21, 2015. The full 
text of this document is available for inspection and copying during 
normal business hours in the FCC Reference Center, 445 12th Street SW., 
Washington, DC 20554. The full text may also be downloaded at: 
www.fcc.gov. Alternative formats are available to persons with 
disabilities by sending an email to fcc504@fcc.gov or by calling the 
Consumer & Governmental Affairs Bureau at 202-418-0530 (voice), 202-
418-0432 (tty).

Comment Filing Instructions

    Pursuant to Sec. Sec.  1.415 and 1.419 of the Commission's rules, 
47 CFR 1.415 and 1.419, interested parties may file comments and reply 
comments on or before the dates indicated on the first page of this 
document. Comments may be filed using the Commission's Electronic 
Comment Filing System (ECFS). See Electronic Filing of Documents in 
Rulemaking Proceedings, 63 FR 24121, May 1, 1998.
     Electronic Filers: Comments may be filed electronically 
using the Internet by accessing the ECFS: https://fjallfoss.fcc.gov/ecfs2/.
     Paper Filers: Parties who choose to file by paper must 
file an original and one copy of each filing. If more than one docket 
or rulemaking number appears in the caption of this proceeding, filers 
must submit two additional copies for each additional docket or 
rulemaking number.
    Filings can be sent by hand or messenger delivery, by commercial 
overnight courier, or by first-class or overnight U.S. Postal Service 
mail. All filings must be addressed to the Commission's Secretary, 
Office of the Secretary, Federal Communications Commission.
     All hand-delivered or messenger-delivered paper filings 
for the Commission's Secretary must be delivered to FCC Headquarters at 
445 12th St. SW., Room TW-A325, Washington, DC 20554. The filing hours 
are 8:00 a.m. to 7:00 p.m. All hand deliveries must be held together 
with rubber bands or fasteners. Any envelopes and boxes must be 
disposed of before entering the building.
     Commercial overnight mail (other than U.S. Postal Service 
Express Mail and Priority Mail) must be sent to 9300 East Hampton 
Drive, Capitol Heights, MD 20743.
     U.S. Postal Service first-class, Express, and Priority 
mail must be addressed to 445 12th Street SW., Washington DC 20554.
    People with Disabilities: To request materials in accessible 
formats for people with disabilities (braille, large print, electronic 
files, audio format), send an email to fcc504@fcc.gov or call the 
Consumer & Governmental Affairs Bureau at 202-418-0530 (voice), 202-
418-0432 (tty).

Ex Parte Rules

    This proceeding shall continue to be treated as a ``permit-but-
disclose'' proceeding in accordance with the Commission's ex parte 
rules. See 47 CFR 1.1200 et seq. Persons making ex parte presentations 
must file a copy of

[[Page 34120]]

any written presentation or a memorandum summarizing any oral 
presentation within two business days after the presentation (unless a 
different deadline applicable to the Sunshine period applies). Persons 
making oral ex parte presentations are reminded that memoranda 
summarizing the presentation must (1) list all persons attending or 
otherwise participating in the meeting at which the ex parte 
presentation was made, and (2) summarize all data presented and 
arguments made during the presentation. If the presentation consisted 
in whole or in part of the presentation of data or arguments already 
reflected in the presenter's written comments, memoranda or other 
filings in the proceeding, the presenter may provide citations to such 
data or arguments in his or her prior comments, memoranda, or other 
filings (specifying the relevant page and/or paragraph numbers where 
such data or arguments can be found) in lieu of summarizing them in the 
memorandum. Documents shown or given to Commission staff during ex 
parte meetings are deemed to be written ex parte presentations and must 
be filed consistent with Sec.  1.1206(b). See 47 CFR 1.1206(b). In 
proceedings governed by Section 1.49(f), 47 CFR 1.49(f), or for which 
the Commission has made available a method of electronic filing, 
written ex parte presentations and memoranda summarizing oral ex parte 
presentations, and all attachments thereto, must be filed through the 
electronic comment filing system available for that proceeding, and 
must be filed in their native format (e.g., .doc, .xml, .ppt, 
searchable .pdf). Participants in this proceeding should familiarize 
themselves with the Commission's ex parte rules.
    We note that our ex parte rules provide for a conditional exception 
for all ex parte presentations made by NTIA or Department of Defense 
representatives. See 47 CFR 1.1204. This Second FNPRM raises 
significant technical issues implicating federal and non-federal 
spectrum allocations and users. Staff from NTIA, DoD, and the FCC have 
engaged in technical discussions in the development of this Second 
FNPRM, and we anticipate these discussions will continue after this 
Second FNPRM is released. These discussions will benefit from an open 
exchange of information between agencies, and may involve sensitive 
information regarding the strategic federal use of the 3.5 GHz Band. 
Recognizing the value of federal agency collaboration on the technical 
issues raised in this Second FNPRM, NTIA's shared jurisdiction over the 
3.5 GHz Band, the importance of protecting federal users in the 3.5 GHz 
Band from interference, and the goal of enabling spectrum sharing to 
help address the ongoing spectrum capacity crunch, we find that this 
exemption serves the public interest.

Initial Paperwork Reduction Act Analysis

    This Second FNPRM contains proposed new information collection 
requirements. The Commission, as part of its continuing effort to 
reduce paperwork burdens, invites the general public and the Office of 
Management and Budget (OMB) to comment on the information collection 
requirements contained in this FNPRM, as required by the Paperwork 
Reduction Act of 1995, Public Law 104-13. In addition, pursuant to the 
Small Business Paperwork Relief Act of 2002, Public Law 107-198, we 
seek specific comment on how we might ``further reduce the information 
collection burden for small business concerns with fewer than 25 
employees.''

Synopsis of the Second Further Public Notice of Proposed Rulemaking

I. Introduction

    On April 21, 2015, the Federal Communications Commission released a 
Report and Order and Second Further Notice of Proposed Rulemaking 
(``Report and Order'' and ``Second FNPRM'') in this proceeding to 
establish a new Citizens Broadband Radio Service in the 3.5 GHz Band. 
While the Report and Order set forth a complete set of rules and 
policies related to the establishment of the Citizens Broadband Radio 
Service, we determined that a few focused issues remained that would 
benefit from further record development. We viewed these issues as 
opportunities to optimize the rules we had established. In the Second 
FNPRM, the Commission sought focused comment to the specific proposals 
and questions discussed below. In addition, we encouraged parties to 
converge on practical, multi-stakeholder solutions.

II. Background

    In the Report and Order, the Commission adopted rules for 
commercial use of 150 megahertz in the 3550-3700 MHz band (3.5 GHz 
Band). The 3.5 GHz Band is currently used for Department of Defense 
Radar services and commercial fixed Satellite Service (FSS) earth 
stations (space-to-earth). The creation of a new Citizens Broadband 
Radio Service in this band will add much-needed capacity to meet the 
ever-increasing demands of wireless innovation. As such, it represents 
a major contribution toward the Commission's goal of making 500 
megahertz newly available for broadband use and will help to unleash 
broadband opportunities for consumers throughout the country, 
particularly in areas with overburdened spectrum resources.
    The Report and Order also adopts a new approach to spectrum 
management, which makes use of advances in computing technology to 
facilitate more intensive spectrum sharing: Between commercial and 
federal users and among multiple tiers of commercial users. This three-
tiered sharing framework is enabled by a Spectrum Access System (SAS). 
The SAS incorporates a dynamic spectrum database and interference 
mitigation techniques to manage all three tiers of authorized users 
(Incumbent Access, Priority Access, and General Authorized Access 
(GAA)). The SAS thus serves as an advanced, highly automated frequency 
coordinator across the band--protecting higher tier users from those 
beneath and optimizing frequency use to allow maximum capacity and 
coexistence in the band.
    Incumbent users represent the highest tier in the new 3.5 GHz 
framework and receive interference protection from Citizens Broadband 
Radio Service users. Protected incumbents include the federal 
operations described above, as well as FSS and, for a finite period, 
grandfathered terrestrial wireless operations in the 3650-3700 MHz 
portion of the band. The Citizens Broadband Radio Service itself 
consists of two tiers--Priority Access and GAA--both authorized in any 
given location and frequency by an SAS. As the name suggests, Priority 
Access operations receive protection from GAA operations. Priority 
Access Licenses (PALs), defined as an authorization to use a 10 
megahertz channel in a single census tract for three years, will be 
assigned in up to 70 megahertz of the 3550-3650 MHz portion of the 
band. GAA will be allowed, by rule, throughout the 150 megahertz band. 
GAA users will receive no interference protection from other Citizens 
Broadband Radio Service users. In general, under this three-tiered 
licensing framework incumbent users will be able to operate on a fully 
protected basis, while the technical benefits of small cells are 
leveraged to facilitate innovative and efficient uses in the 3.5 GHz 
Band.

[[Page 34121]]

III. Discussion

A. Defining ``Use'' of PAL Frequencies

    In the Report and Order, we determined that allowing opportunistic 
access to unused Priority Access channels would serve the public 
interest by maximizing the flexibility and utility of the 3.5 GHz Band 
for the widest range of potential users. Thus, when Priority Access 
rights have not been issued (e.g., due to lack of demand) or the 
spectrum is not actually in use by a Priority Access licensee, the SAS 
will automatically make that spectrum available for GAA use on a local 
and granular basis. While there was substantial support in the record 
for an opportunistic use approach generally, we saw wide divergence in 
the record to-date regarding specific implementation of our ``use-it-
or-share-it'' rule. We thus sought focused comment on specific options, 
rooted in the record, for defining ``use'' by Priority Access 
licensees.
    Engineering Definition. Several commenters provided versions of an 
approach that would rely on an engineering definition of ``use,'' 
effectively leveraging the SAS to define a boundary that would forbid 
GAA access near Priority Access CBSDs. Google maintained that an SAS 
can enforce Priority Access user protection areas based on information 
such as the Priority Access device's location and technical 
characteristics. According to Google, the SAS can protect the Priority 
Access device from nearby GAA operations including the aggregate effect 
of multiple devices operating in the vicinity. Google, at various 
points in the record, suggests versions of this approach with differing 
levels of complexity, ranging from use of simple distance-based metrics 
to methods based on site-specific propagation modeling. Pierre de Vries 
offers another variation of this concept, based on ``interference 
limits policy,'' specifically the use of defined ``reception limits'' 
to specify GAA operation that does not degrade the performance of 
Priority Access systems.
    According to Pierre de Vries, the Commission could specify the 
``maximum allowed resulting signal strength at the protected receiver 
and let an SAS calculate the allowed GAA transmit power.'' AT&T 
suggests that 3GPP standards for TD-LTE channel occupancy could be used 
to determine channel usage. Federated Wireless proposes that GAA 
devices could provide the SAS with ``spectrum sensing data'' upon 
initial operation and at regular intervals as directed by the SAS. 
Federated Wireless recommends that an industry group be convened to 
develop the details of such a sensing framework, including the 
measurement procedure, reporting protocol, and occupancy and evacuation 
times. WISPA proposes that ``any CBSD that has not received 300 end-
user packets within each five-minute interval would be deemed by the 
SAS to be not `in use.' '' Other commenters, including Microsoft, PISC, 
and Shared Spectrum Company suggest that GAA use be permitted in PAL 
spectrum until a Priority Access licensee affirmatively requests access 
to its PAL from the SAS. InterDigital suggests that evacuation commands 
be signaled to GAA users via the SAS, which will allow for flexible 
channel evacuation times.
    We seek comment on whether we should adopt an engineering 
definition of ``use.'' We ask proponents of this approach to develop, 
in detail, an engineering methodology along with technical criteria and 
metrics that could be readily implemented by multiple, coordinated 
SASs. We also ask proponents to address some specific concerns about 
the engineering approach.
    First, we note Verizon's observation that there may be occasions 
when a vacant channel performs a productive use, for example by serving 
as a guard band. Is this claim valid given the technical rules we have 
adopted in the Report and Order (e.g., for Category A and Category B 
CBSDs)? In cases where a vacant channel is serving as a guard band for 
high or full power use, could it be usable for localized communications 
at lower powers (e.g., a few milliwatts) or indoor operations?
    Second, we speculate that it might be possible for Priority Access 
licensees to deploy low-cost CBSDs whose main purpose is to trigger SAS 
protections. We further observe that policing ``license savers'' has 
historically been a very challenging and administratively costly 
endeavor for the Commission. How could we prevent such gaming of the 
use-or-share rules, while maintaining our goals of technological 
flexibility, administrative simplicity, and light-touch regulation?
    Third, the prospect of basing determinations of ``use'' on 
aggregate interference metrics raises equitable and coordination 
challenges with respect to the GAA tier. As discussed above, reliance 
on aggregate interference begs the question of which GAA user will be 
denied access when the aggregate threshold is exceeded. Therefore, we 
are not comfortable delegating this decision to third parties absent 
the adoption of an equitable and non-discriminatory methodology. We 
seek comment on whether and how aggregate metrics could be used to 
facilitate coordination among multiple SASs? Would the use of aggregate 
metrics introduce complexities that would outweigh the potential 
benefits of using such metrics? If we were to utilize an approach based 
on aggregate interference, how could we overcome these significant 
concerns? Alternatively, are there simpler, non-aggregate engineering 
metrics available that sidestep our concerns, perhaps with slightly 
less optimal spectrum utilization?
    Economic Definition. An alternative approach presented in the 
record is to define ``use'' from an economic perspective for the 
purposes of determining GAA access to PAL spectrum. William Lehr, an 
economist at the Massachusetts Institute of Technology, proposes that 
we ``view the PAL as an option to exclude GAA usage. PAL licensees 
would acquire the right to exclude GAA access.'' Under this approach, 
actual operation as a PAL licensee would not be a trigger for excluding 
GAA use. A PAL licensee would have the right, but not the obligation, 
to exercise its option and thus exclude GAA access from the PAL. The 
amount ultimately paid by the licensee would depend on whether the 
option is exercised and GAA access is correspondingly restricted. Lehr 
elaborates that in a simple implementation, ``A winning bidder (with a 
bid of P for a PAL) would expect to owe \1/2\ P when the license is 
awarded and \1/2\ P when the licensee elects to exercise the option to 
exclude. The opportunity to delay payment would provide winning bidders 
with an economic incentive to avoid excluding GAA users unless the 
benefits of such exclusion outweigh the costs of exercising.'' Lehr 
argues that the options approach offers multiple benefits, including: 
More efficient spectrum usage and expanded access for commercial users; 
increased participation of PAL and GAA commercial users by enabling 
better matching of PAL costs with network investment requirements and 
by expanding access for GAA; simple and low-cost implementation; 
reduced potential risk of PAL spectrum hoarding by PAL; and, 
flexibility and consistency with future dynamic shared spectrum policy. 
He also addresses some potential concerns, including: Enforceability; 
auction revenue impact; foreclosure of GAA use; and mispricing of 
options payments. Lehr concludes by addressing some additional 
implementation details such as the ``reversibility'' of license

[[Page 34122]]

payments and the possibility of trading option rights on a secondary 
market.
    We seek comment on whether Lehr's economic construction of ``use'' 
would be appropriate for determining GAA admission to PAL frequencies 
as the concept may provide a potential way to avoid some of the 
concerns raised above with respect to an engineering approach. At the 
same time, the proposal raises other issues, some of which, as noted 
above, Lehr discusses in his comments. We seek comment on these 
concerns.
    First, we seek comment on hoarding. Would the option framework 
encourage or discourage hoarding of PAL spectrum? How does the risk of 
hoarding using options compare against the risk of hoarding through 
deployment of low-cost CBSDs (discussed above) in an engineering-based 
approach?
    Second, how should we think about the payments and pricing of PALs? 
In the FNPRM, the Commission sought comment on employing its existing 
rules to address upfront, down and final payments by winning bidders, 
applications for licenses by winning bidders, as well as the processing 
of such applications and default by and disqualification of winning 
bidders. The Commission sought comment on whether its existing rules 
required any revisions in connection with the conduct of an auction of 
PALs. We did not receive a sufficient record to determine what payment, 
application, and default rule revisions are necessary in adopting a 
less traditional approach to licensing the PAL spectrum. For instance, 
if we adopt the economic definition of ``use'' proposed above, would a 
50/50 split between initial payments and an option ``strike'' price 
provide appropriate incentives for PAL use (or non-use)? We also seek 
renewed comment on the other payment, application and default questions 
raised in the FNPRM in the event that we adopt one of the proposals 
discussed above.
    Third, how would the options approach fit not only with our 
auctions authority under 47 U.S.C. 309(j) but also decades of 
experience in holding auctions? Would an option scheme, such as that 
proposed here, be sufficiently distinguishable from the Commission's 
prior use of installment payments since under this proposal the full 
rights in the license would presumably not be perfected until the time 
of a second payment? Would the use of a two-payment option, in 
practice, lead to complications similar to those experienced in the 
past with installment payments? Is the Commission's existing legal 
authority sufficient to permit it to adopt auction and payment rules to 
implement this option? We note that our auction authority is limited to 
the award of an initial ``license'' (or permit), and that the Act 
defines a license not as the right to exclude others but rather as an 
``instrument of authorization . . . for the use or operation of 
apparatus for transmission . . .'' In the case of the options approach, 
could economic performance serve as a legally viable substitute for 
traditional build out or service-based performance requirements? Are 
there any statutory or other legal considerations that the Commission 
should consider in revising its existing payment, application and 
default rules to accommodate these proposals?
    Hybrid Definition. We also seek comment on any hybrid proposals 
that combine aspects of the engineering and economic approaches. For 
example, Federated Wireless suggests that Priority Access licensees, in 
the context of their proposed sensing framework, should pay a ``nominal 
usage fee for those periods that the spectrum [is] actively needed.'' 
Federated maintains that such a usage fee would incentivize Priority 
Access licensees to only reserve spectrum that they intend to use. 
Could we think of such a usage fee as a form of ``option'' superimposed 
on an engineering definition of ``use''? Do we have authority to impose 
such a fee and, if so, how would we set the price? How would we define 
the unit volume (i.e., quantity) of ``use'' to which a price could be 
applied? Could such a framework make use of an auction, with price set 
through competitive bidding, rather than a fee? Could the auction 
payment be pro-rated across sub-divisions of the license area (e.g., 
Census Block Groups) to account for use in only a portion of the 
geography? What would be the simplest and most practical approach to 
implementing a hybrid scheme?

B. Implementing Secondary Markets in Priority Access Licenses

    In the Further Notice of Proposed Rulemaking (79 FR 31247, June 2, 
2014) in this proceeding, we sought comment on the extent to which our 
existing secondary market rules (both for license transfers and for 
leases) might be appropriately modified with respect to the secondary 
market for PALs in the 3.5 GHz Band. We emphasized that auctions would 
be our initial assignment methodology, but that the secondary market 
could provide a viable means of matching supply and demand in units 
more granular than our proposed PAL structure. We noted that the 
development of one or more spectrum exchanges, operating pursuant to 
our secondary market rules, could facilitate a vibrant and deep market 
for PAL rights.
    Relatively few commenters addressed the significant issues 
associated with the potential application of our secondary market rules 
to the transfer of PALs. Commenters who did address the issue were 
generally supportive of a framework in which PALs can been traded in 
the secondary market. These commenters note that the development of a 
robust secondary market in the 3.5 GHz Band would be beneficial for 
potential Priority Access Licensees. AT&T, for example, believes that 
flexibility in the deployment of PALs will be important to both 
commercial operators and other Priority Access Licensees as PAL use may 
be short term, e.g., coverage for a large event, or longer term, e.g., 
backhaul or access applications. AT&T maintains that partitioning and a 
secondary market mechanism will enable Priority Access licensees to 
gain access to additional spectrum as future needs arise. Qualcomm and 
WISPA support affording PAL licensees the flexibility to disaggregate 
or partition their licenses. In addition, WISPA and Spectrum Bridge 
argue that prior Commission approval of secondary market transactions 
should not be required given the absence of build-out rules for the 
band and a streamlined auction process, among other reasons. Instead, 
WISPA argues that written notification to the Commission and SAS would 
be sufficient to ensure that appropriate contact information is 
available in the event of harmful interference. TIA also supports 
application of the Commission's secondary market rules and emphasizes 
the need for secondary leasing arrangements, which will ``allow 
providers to adjust to changing market circumstances in order to 
enhance their service quality.'' Federated Wireless, on the other hand, 
opposes application of the secondary market rules noting that ``[t]he 
development of secondary markets to manage geographical subsets of PALs 
takes the control of spectrum management and enforcement out of the 
hands of the SAS and the FCC.''
    Some commenters support the development of one or more spectrum 
exchanges, operating pursuant to our secondary market rules, which 
could facilitate a vibrant and deep market for PAL rights. Such an 
exchange could improve the ability of individual licensees to obtain 
micro-targeted (in geography, time, and bandwidth) access to priority 
spectrum rights narrowly tailored to their needs on a highly

[[Page 34123]]

customizable, fluid basis. Cantor proposes a spectrum exchange managed 
by an independent third party and modeled on platforms which exist for 
the trading of other U.S. Government securities. Cantor envisions that 
such a spectrum exchange would integrate the SAS functions in order to 
provide market participants with use right information and to resolve 
any interference issues that might arise. In addition, Cantor explains 
that a spectrum exchange should include: ``(1) Universal access to 
information; (2) dynamic transactional access by and among authorized 
market participants; (3) real-time reporting of 3.5 GHz spectrum 
resource use right utilization; and (4) market maintenance.'' 
InterDigital suggests that the SAS could act as a spectrum exchange to 
manage secondary market transactions. We note that any spectrum 
exchange would be subject to the requirements of Section 310(d) of the 
Communications Act and other relevant statutory provisions.
    We believe that it is in the public interest to develop a fuller 
record on the implications of applying our secondary market rules to 
the 3.5 GHz Band ecosystem. While we agree with commenters on the 
record thus far that application of our secondary market rules will 
increase liquidity of the spectrum as well as reduce costs and increase 
flexibility of use, we seek additional information on how we should 
implement the rules with respect to the 3.5 GHz Band. To the extent 
that commenters agree with this concept, we request specific and 
focused comment on any necessary changes to our Part 1 rules to 
facilitate the secondary market for PALs in the 3.5 GHz Band. For 
example, regarding partitioning and disaggregation, our initial view is 
to prohibit such further segmentation of PALs given their relatively 
small size (census tracts) and limited duration (three years) as well 
as the availability of significant GAA spectrum in all license areas. 
Some commenters, however, urge the Commission to allow partitioning and 
disaggregation of PALs. We seek comment on this proposal. Would 
partitioning and disaggregation of PALs benefit the Citizens Broadband 
Radio Service or would such flexibility prove administratively 
burdensome and unnecessary given the size and duration of these 
licenses? We also seek comment on the potential use of spectrum 
exchanges to facilitate the transfer of PALs in the secondary market. 
Would such exchanges be mandatory or could the existing Part 1 rules, 
in combination with the SAS framework adopted in the Report and Order, 
above, be sufficient to allow voluntary development of exchanges to 
trade PALs? We are particularly interested in modifications to our 
rules that could reduce transaction costs and allow increased 
automation of transfer and lease applications. What legal, technical, 
or logistical issues should we consider?
    For secondary markets purposes, we also seek comment on the 
application of our spectrum aggregation limits for PAL licensees. 
Should we use the attribution standard applied in our existing rules to 
transactions involving mobile wireless licenses for commercial use? We 
also seek comment on how this standard can reflect the need for a 
streamlined process, potentially through a database administrator, for 
transactions involving PALs. In addition, we seek comment on the 
application of our spectrum aggregation limit in the context of the 
initial licensing of PALs, including how any unique characteristics of 
PAL auctions, such as the need for streamlined processing, should be 
taken into account in resolving this issue.

C. Optimizing Protections for FSS

1. In-Band Protection of FSS in the 3650-3700 MHz Band
    We raise five topics for consideration in the Second FNPRM with 
respect to the methodology and parameters for protecting in-band FSS 
earth stations, in addition to the adoption of Section 96.17 as 
described in section III(G)(2) of the Report and Order.
    Calculation Methodology. As noted in the Report and Order, we agree 
with Google that the Commission's example methodology in the 3650-3700 
MHz proceeding is a useful starting point for coexistence analysis. We 
seek comment on the use of this methodology by the SAS to calculate 
exclusion distances for CBSDs with respect to individual FSS earth 
stations in the 3650-3700 MHz band. Is the methodology accurate? Does 
it require further specification?
    Propagation Modeling. While we recognize the challenge of effective 
propagation modeling for band sharing, we believe that research in 
propagation path loss models in recent years has advanced considerably 
and offers an increasing array of practical and realistic tools and 
methods for predicting path loss and determining practical bounds on 
prediction errors. However, despite these advances, there are many 
different propagation models, with little integration of these models 
across diverse environments. Many existing models have been tailored 
for specific and diversely different environments. A research article 
by Phillips, Sicker, and Grunwald illustrates the scope of the 
challenge as well as the significant benefit of improved statistical 
analysis of path loss prediction. They described and implemented ``30 
propagation models of varying popularity that have been proposed over 
the last 70 years'' and found ``. . . the landscape of path loss models 
is precarious . . . we recommend the use of a few well-accepted and 
well-performing standard models in scenarios where a priori predictions 
are needed and argue for the use of well-validated, measurement-driven 
methods whenever possible.'' We agree with this finding and believe 
that improved statistical analysis of propagation path loss can lead to 
significant improvements in shared spectrum utilization and 
interference prediction and mitigation. We propose that all SAS 
Administrators use an agreed upon set of propagation modeling methods, 
using models that can be tuned with measurements. We seek comment on 
what propagation model(s) are best suited for SAS-based protections of 
FSS. We solicit measurement results that validate model parameters for 
combined short range and long range propagation scenarios, involving 
indoor and outdoor propagation channels. What model(s) are the most 
accurate in accounting for urban clutter and other environmental 
factors such as rain attenuation, ducting, etc., and most suitable for 
modeling statistical variations to support analysis--including possible 
Monte-Carlo analysis--of many potential interfering sources? In order 
to generate the same exclusion distances between CBSDs and any 
individual FSS earth stations in 3650-3700 MHz, we expect each SAS to 
enforce the same minimum separation distance and we tentatively 
conclude that each SAS must use the same propagation model. We seek 
comment and objective analysis from anyone who believes otherwise.
    Interference Protection Criteria. We agree with commenters that, in 
principle, an Equivalent Power Flux Density (EPFD) of aggregate 
interference power at the FSS earth station receiver could be an 
appropriate interference protection criterion (IPC) for establishing 
interference limits of FSS earth stations. However, our equitable and 
competitive concerns about using aggregate limits is noted above and 
discussed further below. Were we to adopt an aggregate level, we 
believe it should be based not only on the theoretical thermal noise 
floor (I/N), but should also account for the measurement of receiver 
performance degradation when presented with both

[[Page 34124]]

interfering signals and wanted desired signals (C/(I+N)). We seek 
comment on the appropriate FSS earth station interference protection 
criteria, the appropriate probability of such threshold not being 
exceeded, and supporting field measurements to validate such proposals. 
Commenters should assume the use of appropriate, commercially available 
earth station receiver input filtering to limit the receiver bandwidth 
to the authorized spectrum.
    We propose that co-channel Citizens Broadband Radio Service Device 
(CBSD) and End User Device signal levels up to this threshold be 
permissible, at the antenna output after FSS earth station antenna gain 
and discrimination per section 25.209(a)(3) of our rules. We propose 
that the SAS will calculate the distance, bearing, and elevation 
differences between registered FSS earth stations and each CBSD that 
requests activation. The SAS will then authorize CBSD activation if it 
is at or beyond the permissible distance, and deny CBSD activation if 
is less than the permissible distance from the earth station. How 
should existing link budget margins be treated in establishing value(s) 
for interference protection criteria, where such margins are built in 
to FSS earth station link budgets to account for rain attenuation, and 
other impairments? What is the statistical and temporal correlation of 
environmental effects that may not be independent nor occur 
simultaneously (e.g., stable atmosphere anomalous ducting, occurring 
naturally at different times than convective atmospheric heavy rain)? 
We also invite comment as to whether we can establish a default earth 
station protection area based on an assumed minimum earth station 
receiving system gain-to-temperature ratio (G/T) and minimum antenna 
elevation angle, and what the assumed values of the G/T and elevation 
angle should be. CBSD operation outside of such a default protection 
area would be assumed not to cause interference to earth stations 
receiving in the 3700-4200 MHz band. Such a default protection area 
would be adjusted by the SAS to accommodate the actual operating 
characteristics of earth stations that are registered in order to 
achieve additional protection.
    Avoiding Policy Concerns Related to Aggregate Interference 
Protection Criteria (IPC). We seek comment on fair and non-
discriminatory methods of adjudicating demands for increased spectrum 
use at a location that would result in the IPC for an FSS earth station 
receiver being exceeded. SIA has argued that protection zones may be 
insufficient if densely deployed CBSD and End User Devices outside of 
these areas cause aggregate interference thresholds to be exceeded. 
They argue that unless the Commission is prepared to periodically 
revisit and enlarge protection zones to address such events, it will 
need to either set deployment density constraints or build in a 
significant margin in calculating protection zones to account for 
aggregate interference. We seek comment on solutions that avoid 
discriminatory caps on CBSD service deployment, while protecting FSS 
earth stations from harmful interference. For example, are there 
probabilistic ``bilateral'' approximations (between an individual CBSD 
and an earth station) of an aggregate metric that address our concerns 
about the use of aggregate interference protections while also avoiding 
worst-case assumptions about interference from unlikely or infeasible 
quantities of nearby CBSDs? To the extent that commenters do support an 
aggregated EPFD limit, we encourage solutions to avoid a ``land rush'' 
when balancing service demands that exceed interference limits, if they 
occur. How could such IPC criteria be implemented by CBSDs and the SAS?
    End User Devices. Recognizing that CBSDs have geo-location 
requirements and End User Devices do not, the location of End User 
Devices and the propagation channel between such devices and FSS earth 
stations to be protected are indeterminate. We expect CBSDs to be 
deployed such that terrain, buildings, and other forms of clutter can 
be accounted for and will provide a certain amount of propagation loss 
between the CBSD and a nearby FSS earth station to ensure incumbent 
service protection. However, End User Devices served by such CBSDs may 
be portable or mobile and be situated within line-of-sight or near-
line-of-sight propagation, with much less propagation loss between the 
End User Device and FSS earth station than the propagation channel from 
the CBSD to FSS earth station. The indeterminate location of the End 
User Devices and the uncertain propagation channel between them and FSS 
earth stations make it challenging to ensure protection of nearby FSS 
earth stations. Moreover, assuming worst case line-of-sight propagation 
from End User Devices in determining allowable locations for CBSDs can 
lead to unnecessarily large protection distances. We seek comment on 
reasonable methods for ensuring that the mobility, location, and 
orientation of End User Devices are managed effectively to avoid 
excessive interference to in-band FSS earth stations, while avoiding a 
mandate for geo-location requirements on End User Devices.
2. Out-of-Band Protection of C-Band FSS Earth Stations
    As discussed above, we recognize that our stringent out-of-band 
emissions limit of 70 + 10 Log (P), i.e., -40 dBm/MHz, for CBSDs leaves 
potential room for more optimization. On the one hand, additional 
protection may benefit C-Band earth stations when CBSDs or End User 
Devices are located nearby. On the other, -40 dBm/MHz may prove overly 
stringent in situations where Citizens Broadband Radio Service 
operations are distant from FSS earth stations, resulting in reduced 
usability of frequencies near the 3700 MHz band edge. We believe the 
registration and protection mechanisms of the SAS, in place of an 
across-the-board out-of-band limit, could provide a great deal more 
flexibility and protection to benefit FSS operators and Citizens 
Broadband Radio Service users alike. Therefore, we seek further comment 
on whether and how the same IPC used to ensure protection from co-
channel emitters could also be used with respect to out-of-band 
interference from Citizens Broadband Radio Service to C-Band FSS earth 
stations. To the extent that many different stakeholders may find such 
an approach appealing, we encourage industry discussions that could 
lead to a consensus recommendation.
    We seek comment on whether the received power interference 
protection criteria for out-of-band FSS earth stations should be the 
same or different from co-channel protections. Can a default protection 
area be defined based on these criteria and specific assumptions about 
FSS earth station receiving system G/T and minimum antenna elevation 
angle? For example, a C-Band licensee with an earth station having a 
low elevation angle above heavily populated areas may desire protection 
beyond that afforded with the required out-of-band emission limit. The 
licensee may register the earth station, including the antenna gain 
pattern. This information could be used by an SAS to calculate the 
requisite protection distance near the main beam to enable closer CBSD 
operation in the back of the earth station where there is higher 
antenna discrimination and ensure that the IPC is not exceeded.
    Moreover, we agree with Google that market incentives may be 
feasible to encourage industry to deploy radios with improved (lower) 
adjacent emissions and thereby have greater access to spectrum. 
However, we do not see how this can be accomplished

[[Page 34125]]

within the current regime of equipment authorization subject to the 
Commission's Part 2 requirements. We seek comment on how this can 
practically be achieved without burdensome changes to equipment 
authorization requirements that do not currently require precise 
emission measurements below the regulatory thresholds (i.e., the noise 
floor of measurement equipment configurations often mask the emission 
performance of a device below the pass/fail regulatory limit). One 
possibility would be to define a small number of classes of devices, 
that are distinguished by increasingly stringent OOBE limits (e.g., 
Class X complies with -40 dBm/MHz, Class Y with -45 or -50 dBm/MHz, 
Class Z with -60 dBm/MHz, etc.). The device class would be tied to the 
device's FCC ID, and this information communicated to the SAS, which 
could provide protection commensurate with the class of the device. We 
seek comment on whether such a scenario would work, and if so, what 
levels of OOBE limits should be specified and how would those 
correspond to protection distance. At what point would lower OOBE 
limits cease to offer additional benefit, due to other effects such as 
FCC earth station receiver blocking? We also seek comment on whether we 
would need to make changes in our equipment authorization procedures 
and changes to adopted SAS rules.

IV. Procedural Matters

A. Ex Parte Rules

    This proceeding shall continue to be treated as a ``permit-but-
disclose'' proceeding in accordance with the Commission's ex parte 
rules. Persons making ex parte presentations must file a copy of any 
written presentation or a memorandum summarizing any oral presentation 
within two business days after the presentation (unless a different 
deadline applicable to the Sunshine period applies). Persons making 
oral ex parte presentations are reminded that memoranda summarizing the 
presentation must (1) list all persons attending or otherwise 
participating in the meeting at which the ex parte presentation was 
made, and (2) summarize all data presented and arguments made during 
the presentation. If the presentation consisted in whole or in part of 
the presentation of data or arguments already reflected in the 
presenter's written comments, memoranda or other filings in the 
proceeding, the presenter may provide citations to such data or 
arguments in his or her prior comments, memoranda, or other filings 
(specifying the relevant page and/or paragraph numbers where such data 
or arguments can be found) in lieu of summarizing them in the 
memorandum. Documents shown or given to Commission staff during ex 
parte meetings are deemed to be written ex parte presentations and must 
be filed consistent with Sec.  1.1206(b). In proceedings governed by 
section 1.49(f) or for which the Commission has made available a method 
of electronic filing, written ex parte presentations and memoranda 
summarizing oral ex parte presentations, and all attachments thereto, 
must be filed through the electronic comment filing system available 
for that proceeding, and must be filed in their native format (e.g., 
.doc, .xml, .ppt, searchable .pdf). Participants in this proceeding 
should familiarize themselves with the Commission's ex parte rules.
    We note that our ex parte rules provide for a conditional exception 
for all ex parte presentations made by NTIA or Department of Defense 
representatives. This Second FNPRM raises significant technical issues 
implicating federal and non-federal spectrum allocations and users. 
Staff from NTIA, DoD, and the FCC have engaged in technical discussions 
in the development of this Second FNPRM, and we anticipate these 
discussions will continue after this Second FNPRM is released. These 
discussions will benefit from an open exchange of information between 
agencies, and may involve sensitive information regarding the strategic 
federal use of the 3.5 GHz Band. Recognizing the value of federal 
agency collaboration on the technical issues raised in this Second 
FNPRM, NTIA's shared jurisdiction over the 3.5 GHz Band, the importance 
of protecting federal users in the 3.5 GHz Band from interference, and 
the goal of enabling spectrum sharing to help address the ongoing 
spectrum capacity crunch, we find that this exemption serves the public 
interest.

B. Filing Requirements

    Pursuant to Sec. Sec.  1.415 and 1.419 of the Commission's rules, 
interested parties may file comments and reply comments on or before 
the dates indicated on the first page of this document. Comments may be 
filed using: (1) The Commission's Electronic Comment Filing System 
(ECFS), (2) the Federal Government's eRulemaking Portal, or (3) by 
filing paper copies.
    [ballot] Electronic Filers: Comments may be filed electronically 
using the Internet by accessing the ECFS: https://www.fcc.gov/cgb/ecfs/ 
or the Federal eRulemaking Portal: https://www.regulations.gov.
    [ballot] Paper Filers: Parties who choose to file by paper must 
file an original and one copy of each filing. If more than one docket 
or rulemaking number appears in the caption of this proceeding, filers 
must submit two additional copies for each additional docket or 
rulemaking number.
    Filings can be sent by hand or messenger delivery, by commercial 
overnight courier, or by first-class or overnight U.S. Postal Service 
mail. All filings must be addressed to the Commission's Secretary, 
Office of the Secretary, Federal Communications Commission.
    [cir] All hand-delivered or messenger-delivered paper filings for 
the Commission's Secretary must be delivered to FCC Headquarters at 445 
12th St. SW., Room TW-A325, Washington, DC 20554. All hand deliveries 
must be held together with rubber bands or fasteners. Any envelopes 
must be disposed of before entering the building. The filing hours are 
8:00 a.m. to 7:00 p.m.
    [cir] Commercial overnight mail (other than U.S. Postal Service 
Express Mail and Priority Mail) must be sent to 9300 East Hampton 
Drive, Capitol Heights, MD 20743.
    [cir] U.S. Postal Service first-class, Express, and Priority mail 
must be addressed to 445 12th Street SW., Washington DC 20554.
    Comments, reply comments, and ex parte submissions will be 
available for public inspection during regular business hours in the 
FCC Reference Center, Federal Communications Commission, 445 12th 
Street SW., CY-A257, Washington, DC 20554. These documents will also be 
available via ECFS. Documents will be available electronically in 
ASCII, Microsoft Word, and/or Adobe Acrobat.
    To request information in accessible formats (Braille, large print, 
electronic files, audio format), send an email to fcc504@fcc.gov or 
call the FCC's Consumer and Governmental Affairs Bureau at (202) 418-
0530 (voice), (202) 418-0432 (TTY). This document can also be 
downloaded in Word and Portable Document Format (PDF) at: https://www.fcc.gov.

C. Initial Regulatory Flexibility Analysis

    As required by the Regulatory Flexibility Act of 1980, the 
Commission has prepared an Initial Regulatory Flexibility Analysis 
(IRFA) of the possible significant economic impact on small entities of 
the policies and rules adopted and proposed in this document, 
respectively. The IRFA is set forth in

[[Page 34126]]

Appendix C of the Report and Order. Written public comments are 
requested on the IRFA. These comments must be filed in accordance with 
the same filing deadlines as comments filed in response to the Report 
and Order and Second Further Notice of Proposed Rulemaking as set forth 
above, and have a separate and distinct heading designating them as 
responses to the IRFA. The Commission's Consumer and Governmental 
Affairs Bureau, Reference Information Center, will send a copy of this 
Report and Order and Second Further Notice of Proposed Rulemaking, 
including the FRFA and IRFA, to the Chief Counsel for Advocacy of the 
Small Business Administration (SBA).

D. Initial Paperwork Reduction Act Analysis

    This Second FNPRM contains proposed new information collection 
requirements. The Commission, as part of its continuing effort to 
reduce paperwork burdens, invites the general public and OMB to comment 
on the information collection requirements contained in this document, 
as required by PRA. In addition, pursuant to the Small Business 
Paperwork Relief Act of 2002, we seek specific comment on how we might 
``further reduce the information collection burden for small business 
concerns with fewer than 25 employees.''

Federal Communications Commission.
Gloria J. Miles,
Federal Register Liaison Officer.
[FR Doc. 2015-14495 Filed 6-12-15; 8:45 am]
 BILLING CODE 6712-01-P