Request for Confidential Treatment and Exhibits PUBLIC

1216-EX-ST-2015 Text Documents

Google Inc.

2015-11-16ELS_169428

                                                                   PUBLIC REDACTED VERSION

                                                                                     Google Inc.
                                                                       File No. 1216-EX-ST-2015


Date:                 November 16, 2015

Subject:              Public and Redacted Version of Request for Confidential Treatment and
                      Complementary Exhibits

FCC File No:          1216-EX-ST-2015



To Whom It May Concern:

        Google Inc. (Google), pursuant to 5 U.S.C. § 552 and Sections 0.457 and 0.459 of the
Commission's Rules, 47 C.F.R. §§ 0.457, 0.459, hereby requests that certain information
provided in its above-referenced application for Special Temporary Authority (STA) be treated as
confidential and not subject to public inspection. The designated information constitutes
confidential and proprietary information that, if subject to public disclosure, would cause
significant commercial, economic, and competitive harm. As described below, Google’s request
satisfies the standards for grant of such requests set forth in Sections 0.457 and 0.459 of the
Commission’s Rules.

        In accordance with Section 0.459(b) and in support of this request, Google provides the
following information:



1.      Identification of the Information for Which Confidential Treatment is Sought:

       Google’s request for confidential treatment is limited to the following information that
has been redacted from the STA and complementary exhibits. Google does not seek to
withhold from public inspection information necessary for interference mitigation, including
applicant name, contact information, test location, frequency, output power, effective radiated
power, emission characteristics and modulation.

        Exhibit A - Narrative Statement:

        Google requests confidential treatment of the following underlined text from Exhibit A
        that contains confidential and proprietary information regarding the proposed
        tests/experiments:

                  Consistent with the standards set forth in Section 5.61 of the Federal
           Communications Commission’s (FCC’s or Commission’s) Rules, 47 C.F.R. § 5.61,
           Google Inc. (Google) requests Special Temporary Authority (STA) to conduct
           demonstrations of experimental transmitters. The STA is sought for a period of 180
           days beginning on December 16, 2015. Google outlines below its need for the
           requested STA and the reasons that the STA should be granted expeditiously.

                 The STA is needed for development of [REDACTED]. Among other parameters,
           Google will evaluate [REDACTED].

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                                                                                            Google Inc.
                                                                              File No. 1216-EX-ST-2015


                   The equipment used will include [REDACTED] at any given time. [REDACTED]
           radio will be used with [REDACTED] antennas with a gain not to exceed 42.3 dBi. For
           that radio, the maximum equivalent isotropically radiated power (EIRP) will not exceed
           48.3 dBW, regardless of the antenna used. [REDACTED] radio will be used with
           [REDACTED] antennas with a gain not to exceed 48 dBi. Maximum EIRP from this
           radio will not exceed 54 dBW, regardless of the antenna used. While most of Google’s
           testing will use wideband transmissions, Google also seeks authorization to conduct
           limited narrowband testing in the 31 GHz band. Narrowband testing is expected to
           take place over no more than 12 hours during the pendency of the STA.

                  Grant of this STA will not adversely impact any authorized user of RF
           spectrum for the reasons stated below.

                  27.9-28.0 GHz band users (the 27 GHz band): Google’s operations will not
           cause harmful interference to other users of the 27 GHz band.

                       ●   Terrestrial licensees: On Google’s behalf, Comsearch identified 27 GHz
                           band licensees in the common carrier fixed point-to-point microwave
                           service, local television transmission service (LTTS) and local
                           multipoint distribution service (LMDS).1 Notification letters were sent
                           to each of the licensees operating within the vicinity of Google’s
                           proposed testing, informing them of the technical parameters of the
                           proposed experimentation.2 No licensee objected.3
                       ●   Satellite operations: Google’s proposed testing will not interfere with
                           satellite receivers operating in the 27 GHz band. Google has
                           conducted analyses evaluating the potential for interference to
                           geostationary (GSO) satellites, medium-earth orbit (MEO) satellites,
                           and low-earth orbit (LEO) satellites. Each of these analyses is
                           described below.

                           GSO satellites: To assess potential interference to GSO satellites,
                           Google calculated interference levels from the sidelobes of its
                           [REDACTED] antenna into the satellite receiver. The 27 GHz band is
                           allocated for earth-to-space transmissions, so interference with ground
                           station receivers is not a concern.4 Moreover, the 27 GHz transmitter
                           will be pointing at an elevation angle below the horizon, so the main
                           beam will never be pointing toward the satellite receiver. In performing
                           its analysis, Google relied on the technical parameters for GSO
1
  See Exhibit C (Frequency Coordination Report).
2
  Id. at 1.
3
  Id. The technical coordination report specified that Google would use an antenna with a gain of 27 dBi
in its proposed operation. The request for an STA seeks authorization to operate antennas with gains as
low as 22 dBi. However, if Google uses a lower antenna gain, the EIRP in the direction of other authorized
operations would be correspondingly reduced, ensuring that there is no greater potential for interference
to those operations.
4
  See 47 C.F.R. § 2.106.
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                                                                                             Google Inc.
                                                                               File No. 1216-EX-ST-2015


                            satellites set forth in ITU-R Recommendation SF 1601-2.5 In particular,
                            this recommendation suggests a GSO satellite has a maximum receive
                            antenna gain of 55 dBi and a system noise temperature of 500K.6 To
                            approximate worst case conditions, Google assumed that Google’s
                            ground transmitter was located directly in the spot beam of the
                            satellite’s receiver. Google made additional worst case assumptions
                            regarding its own antenna by assuming its antenna has +10 dBi gain in
                            the direction of the GSO satellite receiver.7 Assuming free space
                            propagation between Google’s transmitter and the satellite’s receiver,
                            Google’s analysis showed that any signal received by the satellite from
                            Google’s transmitter would be at least 19.2 dB below the satellite
                            receiver’s thermal noise floor. This equates to at most 0.052 dB in
                            degradation, which should be nearly undetectable on a data link. ITU
                            Recommendation S.1323-2 recommends that internetwork
                            interference caused by the earth and space station emissions of any
                            one other GSO FSS network operating in the same frequency band or
                            bands be limited to 6% of the total system noise power under clear-sky
                            conditions.8 Link degradation of 0.052 dB corresponds to 1.2% of total
                            system noise power.

                            Moreover, the received signal at the GSO satellite is likely is to be even
                            weaker because any satellite antenna pointed at an associated
                            satellite earth station necessarily will be pointing substantially away
                            from Google’s proposed transmitter location. The closest earth station
                            to Google’s terrestrial transmitter is at least 257 km away.9 As a result,
                            any satellite receiver operating in this band will be pointed at a
                            terrestrial location at least 257 km away from Google’s test location,
                            ensuring that its receiver will be a minimum 0.41 degrees off-boresight
                            from the Google transmitter.

                            MEO and LEO satellites: Google’s proposed testing will not interfere
                            with MEO or LEO satellites. A search of the FCC’s IBFS database
                            shows that there are no MEO or LEO earth stations registered in
                            California. Therefore, the closest earth station to Google’s proposed
                            operation can be no closer than the Nevada border, roughly 257

5
  ITU-R Recommendation SF 1601-2, Methodologies for Interference Evaluation from the Downlink of the
Fixed Service Using High Altitude Platform Stations to the Uplink of the Fixed-satellite Service Using the
Geostationary Satellites Within the Band 27.5-28.35 GHz (2007), available at
http://www.itu.int/rec/R-REC-SF.1601-2-200702-I (ITU-R Recommendation SF 1601-2).
6
  Id. at 8.
7
  [REDACTED].
8
  ITU-R Recommendation S.1323-2, Maximum Permissible Levels of Interference in a Satellite Network
(GSO/FSS; Non-GSO/FSS; Non-GSO/MSS Feeder Links) in the Fixed-satellite Service Caused by Other
Codirectional FSS Networks Below 30 GHz (2002), available at https://www.itu.int/rec/R-REC-S.1323/en
(ITU-R Recommendation S.1323-2).
9
  The distance between Google’s operations and the Nevada border is 257 kilometers.
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                                                                                            Google Inc.
                                                                              File No. 1216-EX-ST-2015


                           kilometers away from Google’s proposed operation. If a MEO satellite
                           operates at roughly 8,000 kilometers above the earth’s surface10 and
                           points at an earth station at least 257 kilometers from the edge of
                           Google’s proposed operating area, the MEO satellite’s receive antenna
                           will be off axis from Google’s transmitter in California by at least 1.8
                           degrees. Relying on the antenna patterns recommended in ITU-R
                           Recommendation F.699-7,11 the satellite receive antenna gain in the
                           direction of Google’s operation is at most 30 dBi for MEO satellites.
                           Using a worst case antenna gain of +10 dBi in the direction of the
                           satellite, and a satellite receiver noise temperature of 500K,12 the signal
                           received by a MEO satellite from Google’s transmitter will be at least
                           28 dB below the noise floor. As noted above, ITU Recommendation
                           S.1323-2 recommends that internetwork interference caused by the
                           earth and space station emissions of any one other GSO FSS network
                           operating in the same frequency band or bands be limited to 6% of the
                           total system noise power under clear-sky conditions.13 Transmissions
                           at 28.3 dB below the noise floor correspond to 0.16% of total system
                           noise power and will not cause harmful interference to MEO satellites.

                           To assess potential interference to LEO satellites, Google assumed
                           that such satellites would operate at orbital heights between 500 and
                           2000 kilometers above mean sea level and conducted the same
                           analysis described above.14 Google’s results are summarized in the
                           table below:




10
   O3b Networks operates a MEO satellite in this band, and that satellite operates at an orbital height of
8062 kilometers.
11
   ITU-R Recommendation F.699, Reference Radiation Patterns for Fixed Wireless System Antennas for
Use in Coordination Studies and Interference Assessment in the Frequency Range From 100 MHz to About
70 GHz (2006), available at https://www.itu.int/rec/R-REC-F.699/en.
12
   ITU-R Recommendation SF 1601-2.
13
   ITU-R Recommendation S.1323-2. The ITU has not issued similar recommendations for MEO and LEO
satellites, so Google has assumed that the system noise temperature and antenna gain characteristics
for LEOs and MEOs are similar to those provided in the ITU-R Recommendation S.1323-2.
14
   Mark A. Sturza, LEOs: The Communications Satellites of the 21st Century 1, IEEE Technical
Applications Conference Northcon/96 Conference Record (1996), available at
http://ieeexplore.ieee.org/xpls/abs_all.jsp?arnumber=564754&tag=1.
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                                                                                           Google Inc.
                                                                             File No. 1216-EX-ST-2015



                             Satellite height           500 km          1000 km          2000 km
                             Minimum angle              27 degrees      14 degrees       7 degrees
                             off-boresight from
                             Google operations
                             Maximum receive            10 dBi          15.3 dBi         21.4 dBi
                             antenna gain in
                             direction of Google
                             operations
                             Maximum power of           27.7 dBm        28.2 dBm         27.7 dBm
                             Google signal received     below noise     below noise      below noise
                             by satellite               floor           floor            floor

                           Based on this analysis, the signal received by a LEO satellite from
                           Google’s operation will be at least 27 dB below the receiver noise floor.
                           This interference level, too, is undetectable on a data link. As noted
                           above, ITU Recommendation S.1323-2 recommends that internetwork
                           interference caused by the earth and space station emissions of any
                           one other GSO FSS network operating in the same frequency band or
                           bands be limited to 6% of the total system noise power under clear-sky
                           conditions.15 Transmissions at 27 dB below the noise floor correspond
                           to 0.2% of total system noise power and will not cause harmful
                           interference to LEO and MEO satellites.

                       ●   Unlicensed operations: Google’s proposed testing will not interfere with
                           unlicensed users of the 24.05-29.00 GHz band. Unlicensed use of the
                           band is limited to level sensing radars.16 These low-power radars
                           measure the level, or relative height, of various substances in
                           man-made or natural containers. For example, they may be used to
                           measure levels water basin levels, coal piles, or grain levels in a grain
                           silo.17 The Commission’s rules require their transmit antennas to be
                           oriented downward. Google’s proposed operation will transmit
                           horizontally, and at ground level, the test emissions will not exceed the
                           −14 dBm/MHz EIRP density set forth in the rules for these radars.18
                           [REDACTED]. [REDACTED], the closest possible sensors would be at
                           least 300 meters away, [REDACTED]. [REDACTED]. Moreover, many
                           level probing radars are used in confined spaces where Google’s signal

15
   ITU-R Recommendation S.1323-2.
16
   See 47 C.F.R. §15.256.
17
   In the Matter of Amendment of Part 15 of the Commission’s Rules To Establish Regulations for Tank
Level Probing Radars in the Frequency Band 77-81 GHz, et al., Report and Order and Order, 29 FCC Rcd.
761 ¶ 1 (2014).
18
   See 47 C.F.R. §15.256(g)(3).
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                                                                                            Google Inc.
                                                                              File No. 1216-EX-ST-2015


                           will be further attenuated by obstructions. As a result, there is no risk
                           of harmful interference to unlicensed operations in this band.

                   31.0-31.3 GHz band users (31 GHz band):

                       ●   Terrestrial licensees: Google’s operations also will not cause harmful
                           interference to other users of the 31 GHz band. On Google’s behalf,
                           Comsearch also identified the common carrier fixed point-to-point
                           microwave service, LTTS, and LMDS licensees operating in this band in
                           the vicinity of Google’s proposed operations.19 Notification letters
                           were sent to each of the licensees operating within the vicinity of
                           Google’s proposed testing, informing them of the technical parameters
                           of the proposed experimentation.20 No licensee objected.21

                           Comsearch also identified site-based licenses in the microwave public
                           safety and industrial/business pool services.22 It then performed an
                           analysis to assess the interference into all potentially affected
                           site-based 31 GHz stations in the microwave public safety and
                           industrial/business pool services.23 This analysis shows that no
                           incumbent fixed operations should be affected by the proposed
                           experimental operation.24

                       ●   Federal operations: The Table of Frequency Allocations reflects a
                           federal allocation for standard frequency and time signal-satellite
                           (space-to-earth) operations. Google is not aware of any federal
                           standard frequency and time signal-satellites using the 31 GHz band,
                           but is prepared to coordinate with such satellite operations as
                           necessary. Google is prepared to coordinate with NTIA to ensure that
                           federal operations in the band do not experience harmful interference.

                  International users: Because the test sites are more than 700 kilometers away
           from U.S. borders, no international coordination is required.

                  The proposed experimental operations in the 27 and 31 GHz bands
           accordingly will be conducted without harmful interference to other authorized users.
           For these reasons, Google requests approval of this STA request.


19
   See Exhibit C at 1.
20
   Id.
21
   Id. The notification letters discussed wideband operation. As noted above, Google seeks to conduct a
limited number of narrowband tests. Comsearch’s report notes that since “the narrower emission
bandwidth is within the 31.0 to 31.3 GHz range of the coordinated emission bandwidth and the EIRP is
not increasing, the interference potential is not increased” in the minimal narrowband testing. As such, no
additional coordination with terrestrial licensees should be required. See id. at 8.
22
   Id. at 1.
23
   Id.
24
   Id.
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                                                                               Google Inc.
                                                                 File No. 1216-EX-ST-2015


Exhibit B - Technical Information:

Google requests confidential treatment of the following underlined text from Exhibit B
that contains confidential and proprietary information regarding the proposed
tests/experiments:

  Applicant Name:      Google Inc.
  Applicant FRN:       0016069502


  Legal Contact Details

     Name of Contact      Aparna Sridhar
     Contact Details      Counsel
                          25 Massachusetts Avenue NW, Ninth Floor
                          Washington DC 20001



  Technical Contact Details

     Name of Contact      Chris White
     Contact Details      1600 Amphitheatre Parkway
                          Mountain View, CA 94043
                          Phone: (650) 214-0860
                          Email: cjwhite@google.com



  Ka-Band Transmitter Equipment and Station Details
   Transmitter Equipment (Location 1)

     Equipment                [REDACTED]
     Number of Terminals      [REDACTED]
     Station Class            Fixed
     Location                 37° 20’ 41” N, 122° 12’ 56” W


     Frequency Range                                  Low (GHz)             High (GHz)
     [REDACTED]                                         27.900                28.000


     Radio              Modulation       Emission    Modulation Maximum Maximum
                                        Designator   Bandwidth Power Out  EIRP
     [REDACTED]            QAM          100MD1D       100 MHz          4W        48.3 dBW

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                                                                           Google Inc.
                                                             File No. 1216-EX-ST-2015


Antenna Information (Location 1)

 Antenna #1                          [REDACTED]
 Type                                [REDACTED]
 Quantity                            [REDACTED]
 Gain                                42.3 dBi
 Beam Width at Half-Power Point      1.3 degrees
 Orientation in Horizontal Plane     56 degrees (NE)
 Orientation in Vertical Plane       -2 degrees


 Antenna #2                          [REDACTED]
 Type                                [REDACTED]
 Quantity                            [REDACTED]
 Gain                                22-27 dBi
 Beam Width at Half-Power Point      0.5-3 degrees in azimuth, 10-50 degrees in
                                     elevation
 Orientation in Horizontal Plane     56 degrees (NE)
 Orientation in Vertical Plane       -2 degrees

Transmitter Equipment (Location 2)

 Equipment                                [REDACTED]
 Number of Terminals                      [REDACTED]
 Station Class                            Fixed
 Location                                 37° 25’ 33” N, 122° 4’ 22” W


 Frequency Range                                 Low (GHz)           High (GHz)
 [REDACTED]                                       31.000               31.300




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                                                                                 Google Inc.
                                                                   File No. 1216-EX-ST-2015



     Radio            Modulation        Emission     Modulation     Maximum       Maximum
                                       Designator    Bandwidth      Power Out       EIRP
     [REDACTED]           QAM          300MD1D         300 MHz          4W         54 dBW
     [REDACTED]          BPSK          15M0G1D         15 MHz           4W         54 dBW
     [REDACTED]       Continuous       100HK0N         100 Hz           4W         54 dBW
                      Waveform

   Antenna Information (Location 2)

     Antenna #1                             [REDACTED]
     Type                                   [REDACTED]
     Quantity                               [REDACTED]
     Gain                                   42.3 dBi
     Beam Width at Half-Power Point         1.3 degrees
     Orientation in Horizontal Plane        234 degrees (SW)
     Orientation in Vertical Plane          +2 degrees


     Antenna #2                             [REDACTED]
     Type                                   [REDACTED]
     Quantity                               [REDACTED]
     Gain                                   48 dBi
     Beam Width at Half-Power Point         0.70 degrees
     Orientation in Horizontal Plane        234 degrees (SW)
     Orientation in Vertical Plane          +2 degrees


Exhibit C - Interference Analysis:

Google does not request confidential treatment of Exhibit C.




                                                    Request for Confidential Treatment - Page 9


                                                                         PUBLIC REDACTED VERSION

                                                                                           Google Inc.
                                                                             File No. 1216-EX-ST-2015


2.      Identification of the Commission proceeding in which the information was submitted or
        a description of the circumstances giving rise to the submission.

       The above-referenced Exhibits were submitted to the Commission in support of the STA.
The Exhibits were filed with the Office of Engineering and Technology on November 16, 2015.
For additional information, please see File No. 1216-EX-ST-2015.



3.      Explanation of the degree to which the information is commercial or financial or
        contains a trade secret or is privileged.

        The information requested to be kept confidential has significant commercial value. The
details of the STA tests/experiments may include trade secret information. The Commission
                                                                              25
has clarified that confidential treatment should be afforded to trade secrets. Google’s
tests/experiments and proprietary wireless applications using particular radio frequency
equipment represent a “secret commercially valuable plan” within the meaning of a trade secret
as recognized by the Commission.

        In addition, agreements entered into between Google and the parties that provided
equipment for testing or will provide analysis of test results require that confidential information
of the parties be held in strict confidence, and that such information not be disclosed to any
third party (with limited exceptions not applicable to this request). The manufacturer name and
model number constitutes confidential trade secrets, technical information, and business
information under the agreements.



4.      Explanation of the degree to which the information concerns a service that is
        competitive.

       The services and technologies that are the subject of this STA have not yet been fully
developed but are expected to lead to material developments in markets subject to competition
from multiple U.S. and non-U.S. third parties.



5.      Explanation of how disclosure of the information could result in substantial competitive
        harm.

       The technology under development is highly sensitive and confidential in nature. The
release of such information would provide valuable insight into Google’s technology innovations
and potential business plans and strategies. Public disclosure would jeopardize the value of the



25
  Examination of Current Policy Concerning the Treatment of Confidential Information Submitted to the
Commission, Report and Order, GC Docket No. 96-55, at para. 3, (released Aug. 4, 1998) (defining “trade
secrets” for purpose of Commission rules on confidential treatment).
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                                                                                       Google Inc.
                                                                         File No. 1216-EX-ST-2015


technology under examination by enabling others to utilize Google’s information to develop
similar products in a similar time frame.



6.     Identification of any measures taken by the requesting party to prevent unauthorized
       disclosure.

        Google has taken steps to keep confidential the information set forth in the confidential
exhibits by limiting the number of people involved in the tests/experiments to only those on a
“need to know” basis, and by requiring that any third parties involved in the preliminary analysis
execute robust nondisclosure agreements.



7.     Identification of whether the information is available to the public and the extent of any
       previous disclosures of the information to any third parties.

       The information contained in the confidential exhibits is not available to the public, and
has only been disclosed to third parties pursuant to restrictive safeguards.

         Google voluntarily provides the information to the Commission at this time with the
expectation that it will be treated confidentially in accordance with the Commission's rules. See
Critical Mass Energy Project v. Nuclear Regulatory Comm’n, 975 F.2d 871, 879 (D.C. Cir. 1992)
(commercial information provided on a voluntary basis “is ‘confidential’ for the purpose of
Freedom of Information Act (FOIA) Exemption 4 if it is of a kind that would customarily not be
released to the public by the person from whom it was obtained.”)



8.     Justification of the requested period of confidentiality.

        Google expects that confidential treatment will be necessary for the length of the
proposed experiment and thereafter in order to protect its evolving business and technology
strategies.



9.     Any other information that would be useful in assessing whether this request should be
       submitted.

       The information subject to this request for confidentiality should not be made available
for public disclosure at any time. There is nothing material that public review of this information
would add to the Commission’s analysis of Google’s request for an experimental authorization.

       Moreover, public disclosure of the sensitive information in the confidential exhibits to
the STA after the Commission has ruled on the Request for Confidentiality is not necessary for
the Commission to fulfill its regulatory responsibilities.


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                                                                                      Google Inc.
                                                                        File No. 1216-EX-ST-2015


       Consistent with 47 C.F.R. § 0.459(d)(l), Google requests notification if release of the
information subject to this request is requested pursuant to the FOIA or otherwise, so that
Google may have an opportunity to oppose grant of any such request.

Sincerely yours,


Aparna Sridhar




                                                        Request for Confidential Treatment - Page 12


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                                                                                            Google Inc.
                                                                              File No. 1216-EX-ST-2015


                               EXHIBIT A – NARRATIVE STATEMENT

       Consistent with the standards set forth in Section 5.61 of the Federal Communications
Commission’s (FCC’s or Commission’s) Rules, 47 C.F.R. § 5.61, Google Inc. (Google) requests
Special Temporary Authority (STA) to conduct demonstrations of experimental transmitters.
The STA is sought for a period of 180 days beginning on December 16, 2015. Google outlines
below its need for the requested STA and the reasons that the STA should be granted
expeditiously.

        The STA is needed for development of [REDACTED]. Among other parameters, Google
will evaluate [REDACTED].

        The equipment used will include [REDACTED] at any given time. [REDACTED] radio will
be used with [REDACTED] antennas with a gain not to exceed 42.3 dBi. For that radio, the
maximum equivalent isotropically radiated power (EIRP) will not exceed 48.3 dBW, regardless of
the antenna used. [REDACTED] radio will be used with [REDACTED] antennas with a gain not to
exceed 48 dBi. Maximum EIRP from this radio will not exceed 54 dBW, regardless of the
antenna used. While most of Google’s testing will use wideband transmissions, Google also
seeks authorization to conduct limited narrowband testing in the 31 GHz band. Narrowband
testing is expected to take place over no more than 12 hours during the pendency of the STA.

      Grant of this STA will not adversely impact any authorized user of RF spectrum for the
reasons stated below.

      27.9-28.0 GHz band users (the 27 GHz band): Google’s operations will not cause
harmful interference to other users of the 27 GHz band.

            ●   Terrestrial licensees: On Google’s behalf, Comsearch identified 27 GHz band
                licensees in the common carrier fixed point-to-point microwave service, local
                television transmission service (LTTS) and local multipoint distribution service
                (LMDS).1 Notification letters were sent to each of the licensees operating within
                the vicinity of Google’s proposed testing, informing them of the technical
                parameters of the proposed experimentation.2 No licensee objected.3
            ●   Satellite operations: Google’s proposed testing will not interfere with satellite
                receivers operating in the 27 GHz band. Google has conducted analyses
                evaluating the potential for interference to geostationary (GSO) satellites,
                medium-earth orbit (MEO) satellites, and low-earth orbit (LEO) satellites. Each of
                these analyses is described below.


1
  See Exhibit C (Frequency Coordination Report).
2
  Id. at 1.
3
  Id. The technical coordination report specified that Google would use an antenna with a gain of 27 dBi
in its proposed operation. The request for an STA seeks authorization to operate antennas with gains as
low as 22 dBi. However, if Google uses a lower antenna gain, the EIRP in the direction of other authorized
operations would be correspondingly reduced, ensuring that there is no greater potential for interference
to those operations.
                                                                                        Exhibit A - Page 1


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                                                                                             Google Inc.
                                                                               File No. 1216-EX-ST-2015


                GSO satellites: To assess potential interference to GSO satellites, Google
                calculated interference levels from the sidelobes of its [REDACTED] antenna into
                the satellite receiver. The 27 GHz band is allocated for earth-to-space
                transmissions, so interference with ground station receivers is not a concern.4
                Moreover, the 27 GHz transmitter will be pointing at an elevation angle below the
                horizon, so the main beam will never be pointing toward the satellite receiver. In
                performing its analysis, Google relied on the technical parameters for GSO
                satellites set forth in ITU-R Recommendation SF 1601-2.5 In particular, this
                recommendation suggests a GSO satellite has a maximum receive antenna gain
                of 55 dBi and a system noise temperature of 500K.6 To approximate worst case
                conditions, Google assumed that Google’s ground transmitter was located
                directly in the spot beam of the satellite’s receiver. Google made additional
                worst case assumptions regarding its own antenna by assuming its antenna has
                +10 dBi gain in the direction of the GSO satellite receiver.7 Assuming free space
                propagation between Google’s transmitter and the satellite’s receiver, Google’s
                analysis showed that any signal received by the satellite from Google’s
                transmitter would be at least 19.2 dB below the satellite receiver’s thermal noise
                floor. This equates to at most 0.052 dB in degradation, which should be nearly
                undetectable on a data link. ITU Recommendation S.1323-2 recommends that
                internetwork interference caused by the earth and space station emissions of
                any one other GSO FSS network operating in the same frequency band or bands
                be limited to 6% of the total system noise power under clear-sky conditions.8
                Link degradation of 0.052 dB corresponds to 1.2% of total system noise power.

                Moreover, the received signal at the GSO satellite is likely is to be even weaker
                because any satellite antenna pointed at an associated satellite earth station
                necessarily will be pointing substantially away from Google’s proposed
                transmitter location. The closest earth station to Google’s terrestrial transmitter
                is at least 257 km away.9 As a result, any satellite receiver operating in this band
                will be pointed at a terrestrial location at least 257 km away from Google’s test
                location, ensuring that its receiver will be a minimum 0.41 degrees off-boresight
                from the Google transmitter.



4
  See 47 C.F.R. § 2.106.
5
  ITU-R Recommendation SF 1601-2, Methodologies for Interference Evaluation from the Downlink of the
Fixed Service Using High Altitude Platform Stations to the Uplink of the Fixed-satellite Service Using the
Geostationary Satellites Within the Band 27.5-28.35 GHz (2007), available at
http://www.itu.int/rec/R-REC-SF.1601-2-200702-I (ITU-R Recommendation SF 1601-2).
6
  Id. at 8.
7
  [REDACTED].
8
  ITU-R Recommendation S.1323-2, Maximum Permissible Levels of Interference in a Satellite Network
(GSO/FSS; Non-GSO/FSS; Non-GSO/MSS Feeder Links) in the Fixed-satellite Service Caused by Other
Codirectional FSS Networks Below 30 GHz (2002), available at https://www.itu.int/rec/R-REC-S.1323/en
(ITU-R Recommendation S.1323-2).
9
  The distance between Google’s operations and the Nevada border is 257 kilometers.
                                                                                          Exhibit A - Page 2


                                                                          PUBLIC REDACTED VERSION

                                                                                            Google Inc.
                                                                              File No. 1216-EX-ST-2015


                MEO and LEO satellites: Google’s proposed testing will not interfere with MEO or
                LEO satellites. A search of the FCC’s IBFS database shows that there are no
                MEO or LEO earth stations registered in California. Therefore, the closest earth
                station to Google’s proposed operation can be no closer than the Nevada border,
                roughly 257 kilometers away from Google’s proposed operation. If a MEO
                satellite operates at roughly 8,000 kilometers above the earth’s surface10 and
                points at an earth station at least 257 kilometers from the edge of Google’s
                proposed operating area, the MEO satellite’s receive antenna will be off axis from
                Google’s transmitter in California by at least 1.8 degrees. Relying on the antenna
                patterns recommended in ITU-R Recommendation F.699-7,11 the satellite receive
                antenna gain in the direction of Google’s operation is at most 30 dBi for MEO
                satellites. Using a worst case antenna gain of +10 dBi in the direction of the
                satellite, and a satellite receiver noise temperature of 500K,12 the signal received
                by a MEO satellite from Google’s transmitter will be at least 28 dB below the
                noise floor. As noted above, ITU Recommendation S.1323-2 recommends that
                internetwork interference caused by the earth and space station emissions of
                any one other GSO FSS network operating in the same frequency band or bands
                be limited to 6% of the total system noise power under clear-sky conditions.13
                Transmissions at 28.3 dB below the noise floor correspond to 0.16% of total
                system noise power and will not cause harmful interference to MEO satellites.

                To assess potential interference to LEO satellites, Google assumed that such
                satellites would operate at orbital heights between 500 and 2000 kilometers
                above mean sea level and conducted the same analysis described above.14
                Google’s results are summarized in the table below:




10
   O3b Networks operates a MEO satellite in this band, and that satellite operates at an orbital height of
8062 kilometers.
11
   ITU-R Recommendation F.699, Reference Radiation Patterns for Fixed Wireless System Antennas for
Use in Coordination Studies and Interference Assessment in the Frequency Range From 100 MHz to About
70 GHz (2006), available at https://www.itu.int/rec/R-REC-F.699/en.
12
   ITU-R Recommendation SF 1601-2.
13
   ITU-R Recommendation S.1323-2. The ITU has not issued similar recommendations for MEO and LEO
satellites, so Google has assumed that the system noise temperature and antenna gain characteristics
for LEOs and MEOs are similar to those provided in the ITU-R Recommendation S.1323-2.
14
   Mark A. Sturza, LEOs: The Communications Satellites of the 21st Century 1, IEEE Technical
Applications Conference Northcon/96 Conference Record (1996), available at
http://ieeexplore.ieee.org/xpls/abs_all.jsp?arnumber=564754&tag=1.
                                                                                         Exhibit A - Page 3


                                                                        PUBLIC REDACTED VERSION

                                                                                           Google Inc.
                                                                             File No. 1216-EX-ST-2015



                 Satellite height             500 km             1000 km            2000 km
                 Minimum angle                27 degrees         14 degrees         7 degrees
                 off-boresight from
                 Google operations
                 Maximum receive           10 dBi                15.3 dBi           21.4 dBi
                 antenna gain in direction
                 of Google operations
                 Maximum power of             27.7 dBm below 28.2 dBm below 27.7 dBm below
                 Google signal received       noise floor    noise floor    noise floor
                 by satellite

                Based on this analysis, the signal received by a LEO satellite from Google’s
                operation will be at least 27 dB below the receiver noise floor. This interference
                level, too, is undetectable on a data link. As noted above, ITU Recommendation
                S.1323-2 recommends that internetwork interference caused by the earth and
                space station emissions of any one other GSO FSS network operating in the
                same frequency band or bands be limited to 6% of the total system noise power
                under clear-sky conditions.15 Transmissions at 27 dB below the noise floor
                correspond to 0.2% of total system noise power and will not cause harmful
                interference to LEO and MEO satellites.

            ●   Unlicensed operations: Google’s proposed testing will not interfere with
                unlicensed users of the 24.05-29.00 GHz band. Unlicensed use of the band is
                limited to level sensing radars.16 These low-power radars measure the level, or
                relative height, of various substances in man-made or natural containers. For
                example, they may be used to measure levels water basin levels, coal piles, or
                grain levels in a grain silo.17 The Commission’s rules require their transmit
                antennas to be oriented downward. Google’s proposed operation will transmit
                horizontally, and at ground level, the test emissions will not exceed the −14
                dBm/MHz EIRP density set forth in the rules for these radars.18 [REDACTED].
                [REDACTED], the closest possible sensors would be at least 300 meters away,
                [REDACTED]. [REDACTED]. Moreover, many level probing radars are used in
                confined spaces where Google’s signal will be further attenuated by obstructions.
                As a result, there is no risk of harmful interference to unlicensed operations in
                this band.


15
   ITU-R Recommendation S.1323-2.
16
   See 47 C.F.R. §15.256.
17
   In the Matter of Amendment of Part 15 of the Commission’s Rules To Establish Regulations for Tank
Level Probing Radars in the Frequency Band 77-81 GHz, et al., Report and Order and Order, 29 FCC Rcd.
761 ¶ 1 (2014).
18
   See 47 C.F.R. §15.256(g)(3).
                                                                                       Exhibit A - Page 4


                                                                          PUBLIC REDACTED VERSION

                                                                                            Google Inc.
                                                                              File No. 1216-EX-ST-2015


        31.0-31.3 GHz band users (31 GHz band):

            ●   Terrestrial licensees: Google’s operations also will not cause harmful interference
                to other users of the 31 GHz band. On Google’s behalf, Comsearch also
                identified the common carrier fixed point-to-point microwave service, LTTS, and
                LMDS licensees operating in this band in the vicinity of Google’s proposed
                operations.19 Notification letters were sent to each of the licensees operating
                within the vicinity of Google’s proposed testing, informing them of the technical
                parameters of the proposed experimentation.20 No licensee objected.21

                Comsearch also identified site-based licenses in the microwave public safety and
                industrial/business pool services.22 It then performed an analysis to assess the
                interference into all potentially affected site-based 31 GHz stations in the
                microwave public safety and industrial/business pool services.23 This analysis
                shows that no incumbent fixed operations should be affected by the proposed
                experimental operation.24

            ●   Federal operations: The Table of Frequency Allocations reflects a federal
                allocation for standard frequency and time signal-satellite (space-to-earth)
                operations. Google is not aware of any federal standard frequency and time
                signal-satellites using the 31 GHz band, but is prepared to coordinate with such
                satellite operations as necessary. Google is prepared to coordinate with NTIA to
                ensure that federal operations in the band do not experience harmful
                interference.

       International users: Because the test sites are more than 700 kilometers away from U.S.
borders, no international coordination is required.

       The proposed experimental operations in the 27 and 31 GHz bands accordingly will be
conducted without harmful interference to other authorized users. For these reasons, Google
requests approval of this STA request.




19
   See Exhibit C at 1.
20
   Id.
21
   Id. The notification letters discussed wideband operation. As noted above, Google seeks to conduct a
limited number of narrowband tests. Comsearch’s report notes that since “the narrower emission
bandwidth is within the 31.0 to 31.3 GHz range of the coordinated emission bandwidth and the EIRP is
not increasing, the interference potential is not increased” in the minimal narrowband testing. As such, no
additional coordination with terrestrial licensees should be required. See id. at 8.
22
   Id. at 1.
23
   Id.
24
   Id.
                                                                                         Exhibit A - Page 5


                                                                PUBLIC REDACTED VERSION

                                                                                  Google Inc.
                                                                    File No. 1216-EX-ST-2015


                             EXHIBIT B - TECHNICAL INFORMATION


Applicant Name:         Google Inc.
Applicant FRN:          0016069502


Legal Contact Details

    Name of Contact       Aparna Sridhar
    Contact Details       Counsel
                          25 Massachusetts Avenue NW, Ninth Floor
                          Washington DC 20001




Technical Contact Details

    Name of Contact       Chris White
    Contact Details       1600 Amphitheatre Parkway
                          Mountain View, CA 94043
                          Phone: (650) 214-0860
                          Email: cjwhite@google.com




                                                                             Exhibit B - Page 1


                                                                   PUBLIC REDACTED VERSION

                                                                                       Google Inc.
                                                                         File No. 1216-EX-ST-2015


Ka-Band Transmitter Equipment and Station Details
 Transmitter Equipment (Location 1)

    Equipment                [REDACTED]
    Number of Terminals      [REDACTED]
    Station Class            Fixed
    Location                 37° 20’ 41” N, 122° 12’ 56” W


    Frequency Range                                          Low (GHz)           High (GHz)
    [REDACTED]                                                27.900                 28.000


    Radio                  Modulation      Emission    Modulation        Maximum       Maximum
                                          Designator   Bandwidth         Power Out       EIRP
    [REDACTED]                 QAM        100MD1D        100 MHz            4W         48.3 dBW

 Antenna Information (Location 1)

    Antenna #1                           [REDACTED]
    Type                                 [REDACTED]
    Quantity                             [REDACTED]
    Gain                                 42.3 dBi
    Beam Width at Half-Power Point       1.3 degrees
    Orientation in Horizontal Plane      56 degrees (NE)
    Orientation in Vertical Plane        -2 degrees


    Antenna #2                           [REDACTED]
    Type                                 [REDACTED]
    Quantity                             [REDACTED]
    Gain                                 22-27 dBi
    Beam Width at Half-Power Point       0.5-3 degrees in azimuth, 10-50 degrees in elevation
    Orientation in Horizontal Plane      56 degrees (NE)
    Orientation in Vertical Plane        -2 degrees




                                                                                  Exhibit B - Page 2


                                                                   PUBLIC REDACTED VERSION

                                                                                       Google Inc.
                                                                         File No. 1216-EX-ST-2015


Transmitter Equipment (Location 2)

    Equipment                [REDACTED]
    Number of Terminals      [REDACTED]
    Station Class            Fixed
    Location                 37° 25’ 33” N, 122° 4’ 22” W


    Frequency Range                                         Low (GHz)             High (GHz)
    [REDACTED]                                                31.000               31.300


    Radio                     Modulation     Emission       Modulation    Maximum      Maximum
                                            Designator      Bandwidth     Power Out      EIRP
    [REDACTED]                      QAM      300MD1D         300 MHz         4W         54 dBW
    [REDACTED]                     BPSK      15M0G1D         15 MHz          4W         54 dBW
    [REDACTED]                Continuous     100HK0N         100 Hz          4W         54 dBW
                              Waveform

Antenna Information (Location 2)

    Antenna #1                            [REDACTED]
    Type                                  [REDACTED]
    Quantity                              [REDACTED]
    Gain                                  42.3 dBi
    Beam Width at Half-Power Point        1.3 degrees
    Orientation in Horizontal Plane       234 degrees (SW)
    Orientation in Vertical Plane         +2 degrees


    Antenna #2                            [REDACTED]
    Type                                  [REDACTED]
    Quantity                              [REDACTED]
    Gain                                  48 dBi
    Beam Width at Half-Power Point        0.70 degrees
    Orientation in Horizontal Plane       234 degrees (SW)
    Orientation in Vertical Plane         +2 degrees

                                                                                  Exhibit B - Page 3


                                                    Google Inc.
                                      File No. 1216-EX-ST-2015


EXHIBIT C – FREQUENCY COORDINATION REPORT


             Experimental Operation

                 Mountain View, CA

Frequency Coordination Report – 28 & 31 GHz




    Prepared on Behalf of
        Google Inc.
       November 11, 2015


                                                                               Google Inc.
                                               Experimental Operation in Mountain View, CA
                                                            Frequency Coordination Report
                                                                              28 & 31 GHz


Table of Contents



1.	
     Summary of Results                                                             1	
  

2.	
     Coordination Data                                                              2	
  

3.	
     Common Carrier and LTTS Coordination                                           3	
  

4.	
     LMDS Coordination                                                              4	
  

5.	
     Interference Analysis into Site-Based Licenses                                 5	
  

6.	
     Addendum                                                                       8	
  

7.	
     Contact Information                                                            9	
  


                                                                                       Google Inc.
                                                       Experimental Operation in Mountain View, CA
                                                                    Frequency Coordination Report
                                                                                      28 & 31 GHz


    1. Summary of Results
In support of experimental operations at 28 and 31 GHz1, Comsearch performed a frequency
search considering all existing and proposed incumbent licenses that could potentially be
impacted by the proposed experimental system. The search results identified area licenses in
the common carrier fixed point-to-point microwave service, local television transmission service
(LTTS) and local multipoint distribution service (LMDS). The search also identified site-based
licenses in the microwave public safety and industrial/business pool services.

Prior notification letters were sent to the area-based licensees and a summary of the notification
data is provided in section two of this report. No objections were received from any of the
incumbent licensees for the proposed frequency range of 27.9 – 28.0 GHz and 31.0 – 31.3
GHz. The Google experimental system will be operating on a secondary basis to incumbent
operations, and a point of contact at Google has been provided in case any concerns arise
during operation.

In addition to the above coordination effort, an analysis was performed to assess the
interference into all potentially affected site-based 31 GHz stations in the microwave public
safety and industrial/business pool services. This analysis shows that no incumbent fixed
operations should be affected by the proposed experimental operation.




1
 The experimental system will operate in the 27.9 – 28.0 GHz and 31.0 – 31.3 GHz portions of the 28
GHz / 31 GHz / LMDS band.


Comsearch                                          1                                 November 11, 2015


                                                                                              Google Inc.
                                                              Experimental Operation in Mountain View, CA
                                                                           Frequency Coordination Report
                                                                                             28 & 31 GHz


 2. Coordination Data
This section presents the data pertinent to the experimental system in Mountain View,
California. This data was circulated to all incumbent licensees in the shared 28 and 31 GHz
frequency ranges.



Administrative Information      MTNVIEW1 CA                                       MTNVIEW2 CA
Status / License Basis          Proposed / Non-Interference                       Proposed / Non-Interference
Licensee Name                   GOOGLE INC.                                       GOOGLE INC.
Radio Service / Station Class   XT - Experimental                                 FX -- Fixed

Site Information
Latitude (NAD 83)               37 ° 20’ 41” N                                    37 ° 25’ 33” N
Longitude (NAD 83)              122 ° 12’ 56” W                                   122 ° 4’ 22” W
Ground Elevation (m/ft-AMSL)    497.3 / 1631.55                                   5.48 / 17.99
Path Azimuth (°)                54.508                                            234.595
Path Length (km / miles)                                       15.522 / 9.645

Antenna #1
Description                     2-ft PARABOLIC                                    2-ft PARABOLIC
Gain (dBi)                      42.3                                              42.3
Beamwidth (°)                   1.3                                               1.3
Centerline (m / ft - AGL)       1.8 / 6.0                                         19.8 / 65.0

Antenna #2
Description                     Directional Antenna                               1-meter PARABOLIC
Gain (dBi)                      27.0                                              48.0
Beamwidth (°)                   3.0                                               0.7
Centerline (m / ft - AGL)       1.8 / 6.0                                         19.8 / 65.0

Radio Information
Emission Bandwidth              100 MHz                                           300 MHz
Max EIRP (dBm)                  78.3                                              84.0

Transmit Frequencies (MHz) 27,900-28,000                                          31,000-31,300




Comsearch                                               2                                   November 11, 2015


                                                                                   Google Inc.
                                                   Experimental Operation in Mountain View, CA
                                                                Frequency Coordination Report
                                                                                  28 & 31 GHz


3. Common Carrier and LTTS Coordination
In accordance with FCC Rules and Regulations, the 28/31 GHz experimental system in
Mountain View, California was prior-coordinated by Comsearch. Notification letters for this
system were sent to the following common carrier fixed microwave licensees. These licensees
are authorized to operate temporary fixed operations over a designated geographic area.


 Licensee                                 Band                 Authorized Geographic Area

 AT&T                                     28 GHz, 31 GHz       Continental US
 M.U.T. Licensing, LLC                    28 GHz               Statewide: California
 Verizon                                  28 GHz, 31 GHz       Continental US


A notification letter and datasheet for the experimental system were also sent to the following
28/31 GHz local television transmission licensees. These licensees are authorized to operate
temporary fixed operations on a nationwide basis.


Licensee                                  Band                 Authorized Geographic Area

AT&T California                           31 GHz               Continental US
Information Super Station, LLC            28 GHz, 31 GHz       Continental US
NSM Surveillance                          31 GHz               Continental US
Remote Facilities Consulting Services     31 GHz               Nationwide


No objections were received from the common carrier or local television transmission service
incumbents.




Comsearch                                      3                                November 11, 2015


                                                                                              Google Inc.
                                                              Experimental Operation in Mountain View, CA
                                                                           Frequency Coordination Report
                                                                                             28 & 31 GHz


    4. LMDS Coordination
A Notification letter was sent to the following 28/31 GHz LMDS licensees. The proposed
experimental system will operate on frequencies that overlap Block A and Block B of the LMDS
service. The total frequency allocation for each block of the LMDS spectrum appears below.

Block A:           27.500-28.350 GHz
                   29.100-29.250 GHz
                   31.075-31.225 GHz

Block B:           31.000-31.075 GHz
                   31.225-31.300 GHz


Licensee                                 Block        Market          Market Name

Nextlink/XO                                 B        BTA4042          Sacramento, CA
Straight Path Spectrum                      A         BTA404          San Francisco-Oakland-San Jose, CA
T-Mobile3                                   A         BTA404          San Francisco-Oakland-San Jose, CA
TelePacific Communications4                 A         BTA404          San Francisco-Oakland-San Jose, CA


No objections were received from the LMDS incumbents for the proposed frequency range of
27.9 – 28.0 GHz and 31.0 – 31.3 GHz.




2
    The proposed experimental system will be located inside BTA404.
3
    T-Mobile has acquired LMDS spectrum from Straight Path in the San Francisco-Oakland-San Jose, CA BTA.

4
    Straight Path is leasing spectrum to TelePacific Communications in the San Francisco-Oakland-San Jose, CA BTA.



Comsearch                                                 4                                    November 11, 2015


                                                                                     Google Inc.
                                                     Experimental Operation in Mountain View, CA
                                                                  Frequency Coordination Report
                                                                                    28 & 31 GHz


5. Interference Analysis into Site-Based Licenses
Comsearch performed interference calculations to determine the potential for interference from
Google’s proposed 31 GHz experimental transmitter into site-licensed 31 GHz microwave public
safety and industrial/business incumbent receivers.

As input to the interference study, Comsearch retrieved data for potentially affected 31.0 - 31.3
GHz microwave public safety and industrial/business pool systems from the FCC ULS
database. The systems selected for the analysis include 25 duplex fixed links (50 receivers) in
ULS as well as point-radius licenses west of 110 degrees longitude. The distance limit imposed
by this geographic selection is more than sufficient to ensure that harmful interference with
systems to the east would not occur.

Standard direct interference calculations were used to predict the interference level into each
receiver in the selected data.

For line-of-sight propagation, the interference level at the input to a 31 GHz band receiver is
calculated as:

                          𝐼 = 𝐸𝐼𝑅𝑃(𝛼) − 𝐹𝑆𝐿 − 𝐴𝐵𝑆 + 𝐺! 𝛿 − 𝐿!"#$%
Where:

         EIRP(α)   =   The EIRP of the experimental transmitter as a function of the off-axis
                       angle α (dBm)
         α         =   The experimental transmitter antenna off-axis angle (deg)
         FSL       =   The free-space path loss from experimental transmitter to the receiver
                       (dB)
         ABS       =   The oxygen and water vapor absorption loss for the path from
                       experimental transmitter to receiver (dB)
         Gr        =   The receiver antenna gain (dBi) as a function of the off-axis angle δ
         δ         =   The receiver antenna off-axis angle (deg)
         Lfixed    =   The receiver common and receive-side fixed losses (dB)

Absorption losses were calculated according to the methods of Annex 2 of Recommendation
ITU-R P.676-10. The temperature, atmospheric pressure, and water vapor density parameters
that are required as inputs to the P.676 algorithms were determined at each receiver location
using the methods of Recommendation ITU-R P.835-5 and the associated ITU data banks.

Specific attenuation values (dB/km) for oxygen and water vapor absorption were calculated for
each 31 GHz band receiver in the data set based on the location and antenna height. The total
absorption loss was calculated as the total (water vapor plus oxygen) specific attenuation for the
receiver location times the length of the interference path.

Consistent with FCC rules Section 101.105 and TIA TSB10-F, interference low enough to
degrade the performance of a 31 GHz receiver by less than 1 dB is considered not to be
harmful. The interference objective used in the analysis to satisfy this condition was determined
as follows.


Comsearch                                        5                                November 11, 2015


                                                                                      Google Inc.
                                                      Experimental Operation in Mountain View, CA
                                                                   Frequency Coordination Report
                                                                                     28 & 31 GHz

The thermal noise power level in a receiver is:

                           𝑁 =    −114 + 10 ∗ 𝑙𝑜𝑔!" 𝐵𝑊 + 𝑁𝐹  (𝑑𝐵𝑚)

Where:

         BW    =       The receiver bandwidth in MHz
         NF    =       The receiver noise figure (dB)

The receiver bandwidth is estimated to be the same as the transmitter emission bandwidth
indicated on the license. The receiver noise figure is estimated to be 3 dB.

By power addition, interference at 6 dB below the receiver thermal noise power level would
result in 1 dB degradation of the receiver performance. The interference objective for this
condition is:

                       𝐼!"# = −114 + 10 ∗ 𝑙𝑜𝑔!" 𝐵𝑊 + 𝑁𝐹 − 6  (𝑑𝐵𝑚)

Based on the assumption of a typical 3 dB noise figure, the interference objective for this
analysis is:

                          𝐼!"# = −114 + 10 ∗ 𝑙𝑜𝑔!" 𝐵𝑊 − 3  (𝑑𝐵𝑚)

For each receiver, the predicted interference level under the assumption of line-of-sight
propagation was compared to the 1 dB threshold degradation (TD) objective to determine
whether harmful interference could occur.

Interference Analysis Results
The interference level was calculated into each 31 GHz band receiver in the selected data and
the analysis showed that the interference into all receivers meets the 1 dB TD objective. Thus
Google’s proposed experimental operations are not predicted to cause interference to any of the
incumbent site-based systems at 31 GHz.

Example analysis results to illustrate the calculations are listed in
Table 1 below.




Comsearch                                         6                               November 11, 2015


                                                                                                                                                                                                    Google Inc.
                                                                                                                                                                    Experimental Operation in Mountain View, CA
                                                                                                                                                                                 Frequency Coordination Report
                                                                                                                                                                                                   28 & 31 GHz




                                                                                                        Distance	
                                                                                             Receiver	
  
                                                                                                             from	
         Experimental	
        Experimental	
                              Receiver	
       Antenna	
  
                                                                                                      Experimental	
         Transmitter	
         Transmitter	
          Free-­‐Space	
      Antenna	
         Gain	
  at	
                           Margin	
  to	
  
                                                                  Receiver	
     Experimental	
        Transmitter	
        Antenna	
  Off-­‐      EIRP	
  at	
  Off-­‐    Loss	
  plus	
     Off-­‐Axis	
     Off-­‐Axis	
                             1	
  dB	
  TD	
  
Receiver	
          Transmitter	
         Receiver	
  Site	
     Frequency	
      Transmitter	
        to	
  Receiver	
       Axis	
  Angle	
       Axis	
  Angle	
       Absorption	
          Angle	
         Angle	
          Interference	
        Objective	
  
 Call	
  Sign	
       Call	
  Sign	
         Name	
                (GHz)	
         Site	
  Name	
            (km)	
             (deg)	
               (dBm)	
              Loss	
  (dB)	
       (deg)	
          (dBi)	
          Level	
  (dBm)	
           (dB)	
  
                5
WNTY579 	
           WNTY579	
           SACRAMENTO	
             31.1625,	
      MTNVIEW2	
                 121.9	
            150.3	
                26.0	
                176.7	
             N/A	
  	
       38.2	
             -­‐112.5	
                2.5	
  
                                                                  31.0125	
                                                                                                                    (Omni)	
  
WNTV245	
            WNTV245	
           PALM	
  SPRINGS	
        31.0125,	
      MTNVIEW2	
               642.5	
               107.7	
                26.0	
                227.3	
            N/A	
  	
        38.2	
             -­‐163.1	
            57.9	
  
                                                                  31.0375,	
                                                                                                                   (Omni)	
  
                                                                  31.0625,	
  
                                                                  31.0875,	
  
                                                                  31.1625,	
  
                                                                  31.1875,	
  
                                                                  31.2125	
  
WPJD930	
            WPJD930	
           PALM	
  SPRINGS	
        31.0125,	
      MTNVIEW2	
               643.0	
               107.7	
                26.0	
                227.4	
           N/A	
             38.2	
             -­‐163.2	
            57.9	
  
                                                                  31.0375,	
                                                                                                                   (Omni)	
  
                                                                  31.0625,	
  
                                                                  31.0875,	
  
                                                                  31.1125,	
  
                                                                  31.1625,	
  
                                                                  31.1875,	
  
                                                                  31.2375,	
  
                                                                  31.2625	
  
WPOP444	
            WPOP440	
            RUSSELL	
  RD	
          31075	
        MTNVIEW2	
               646.1	
               133.2	
                26.0	
                228.3	
             2.3	
           20.9	
             -­‐181.4	
            79.4	
  



     Table 1: Example Interference Analysis Results into 31 GHz Site-Based Licenses




     5
       Due to the distance from WNTY579 to the experimental transmitter (121.9 km), Comsearch sent a notification letter to the incumbent licensee. The
     incumbent responded that they have no objection to Google’s proposed system. All other callsigns were of sufficient distance to preclude coordination.

                            Comsearch                                                                                        7                                                            November 11, 2015


                                                                                    Google Inc.
                                                    Experimental Operation in Mountain View, CA
                                                                 Frequency Coordination Report
                                                                                   28 & 31 GHz


6. Addendum
Google will potentially operate narrower emission bandwidths of 100 Hz (CW tone) and 15 MHz
during radio setup of the fixed link. Since the narrower emission bandwidth is within the 31.0 to
31.3 GHz range of the coordinated emission bandwidth and the EIRP is not increasing, the
interference potential is not increased. This short duration operation at the narrower emission
bandwidth is considered a minor revision, and no further analysis is required.




Comsearch                                       8                                November 11, 2015


                                                                                 Google Inc.
                                                 Experimental Operation in Mountain View, CA
                                                              Frequency Coordination Report
                                                                                28 & 31 GHz



7. Contact Information
For questions or information regarding the 28 and 31 GHz Frequency Coordination
Report, please contact:




Contact person:      Joanna Lynch
Title:               Manager, Spectrum & Data Solutions
Company:             Comsearch
Address:             19700 Janelia Farm Blvd., Ashburn, VA 20147
Telephone:           703-726-5711
Fax:                 703-726-5599
Email:               jlynch@comsearch.com
Web site:            www.comsearch.com




Comsearch                                    9                              November 11, 2015



Document Created: 2015-11-16 18:02:54
Document Modified: 2015-11-16 18:02:54

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