Attachment Exhibit A

This document pretains to SES-LIC-20160610-00520 for License on a Satellite Earth Station filing.

IBFS_SESLIC2016061000520_1138490

                                             Exhibit A

                                   Description of Application

        ViaSat, Inc. (“ViaSat”) seeks authority to operate a 9.1 meter, Model VA-91-KA
gateway-type earth station in the Ka band to communicate with the ViaSat-2 satellite, which is
expected to be launched by the first quarter of 2017, and enter into commercial service during
the summer of 2017. To enable satisfaction of the one-year construction deadline for earth
station facilities in Section 25.133(a)(1), this application is being filed approximately 16 months
before the expected in-service date of ViaSat-2. ViaSat is filing a series of thirty-five other
applications for earth stations that will also serve as the critical broadband aggregation and
interconnection facilities for the ViaSat-2 network. Approximately four additional such
applications are expected to be filed shortly.

        The earth station will operate in the 17.7-19.3 GHz and 19.7-20.2 GHz downlink
frequencies and the 27.5-29.1 GHz and 29.5-30.0 GHz uplink frequencies. ViaSat-2, which will
operate under the authority of the United Kingdom, has been approved to serve the United States
in the 18.3-19.3 GHz, 19.7-20.2 GHz, 28.1-29.1 GHz and 29.5-30.0 GHz band segments.1 The
ViaSat-2 Authorization allows the spacecraft to operate (i) in the 18.3-18.8 GHz, 19.7-20.2 GHz,
28.35-28.6 GHz, and 29.5-30.0 GHz frequencies on a primary basis, (ii) in the 28.1-28.35 GHz
on a secondary basis to LMDS and in the 28.6-29.1 GHz frequencies on a secondary basis to
NGSO systems, and (iii) in the 18.8-19.3 GHz frequencies on a non-conforming basis pursuant
to a grant of a waiver of Section 2.106 of the Commission’s rules, and specifically footnote
NG165 thereto. ViaSat has pending an application to modify its authority for ViaSat-2 to
include operations in the 27.5-28.1 GHz band segment on a secondary basis to LMDS and the
17.7-18.3 GHz band segment on a non-conforming basis pursuant to a waiver request.2

        To the extent necessary, ViaSat requests a waiver of the U.S. Table of Frequency
Allocations to allow the earth station to receive communications from ViaSat-2 in the 17.7-18.3
GHz and 18.8-19.3 GHz frequencies on a non-conforming basis.3 Granting waivers to allow the
operation of the earth station in these bands is in the public interest because it will allow ViaSat
to deploy the earth station facilities that will serve as the aggregation and interconnection points
for the ViaSat-2 network. ViaSat-2 incorporates ViaSat’s next-generation satellite technology,
which will utilize this spectrum to provide greater capacity and throughput for a range of
communications services to businesses, consumers and governmental users. Moreover, as
discussed in more detail below, these operations will occur without causing harmful interference
into the services that are designated as primary within the United States.



1
       See IBFS File Nos. SAT-LOI-20130319-00040 (granted Dec. 12, 2013); SAT-MOD-
       20141105-00121 & SAT-AMD-20150105-00002 (granted Apr. 15, 2015); Call Sign:
       2902 (“ViaSat-2 Authorization”).
2
       IBFS File No. SAT-MOD-20160527-00053 (filed May 27, 2016) (“ViaSat-2
       Modification Application”).
3
       47 C.F.R. § 2.106, n.NG165, US271.


I.     CONSISTENCY WITH CO-FREQUENCY OPERATIONS

        The proposed operations are compatible with the operations of adjacent GSO systems, as
well as co-frequency NGSO systems, primary terrestrial users, and BSS feeder link Earth-to-
space transmissions.

       A.      GSO Operations

        Section 25.132(a)(2) provides that earth stations operating in the 18.3-18.8 GHz, 19.7-
20.2 GHz, 28.35-28.6 GHz and 29.5-30.0 GHz band segments must demonstrate compliance
with Section 25.138.4 The antenna meets the performance requirements in Section 25.138(a) in
the direction of the GSO arc, as well as in all other directions, as illustrated by the off-axis EIRP
spectral density plots attached as Exhibit B. ViaSat includes all patterns in digitized format for
all angles up to +/-180 degrees, including the off-axis EIRP density envelope superimposed on
the plots, consistent with the requirements of Section 25.138(d).5 Further, as established in the
Commission’s authorization for the ViaSat-2 satellite, the power flux-density at the earth’s
surface produced by emissions from ViaSat-2 are within the -118 dBW/m2/MHz limit set forth
in Section 25.138(a)(6).

        The receive performance of the antenna complies with the Section 25.209(a) and (b)
mask as revised by the Part 25 Second Report and Order.6 Therefore, the earth station would be
entitled to protection in the 18.3-18.8 GHz and 18.7-20.2 GHz band segments at levels
established in Section 25.209 that is expected to be in effect at the time the requested earth
station authorization is issued.

       B.      NGSO Operations

        Under the ViaSat-2 Authorization, that GSO FSS system may operate in the 28.6-29.1
GHz band segment on a secondary basis with respect to NGSO FSS systems, and in the 18.8-
19.3 GHz band segment on a non-conforming basis.7 NGSO systems are designated as primary
in the U.S. in these frequencies. ViaSat’s proposed earth station operations would not cause


4
       47 C.F.R. § 25.132(a)(2).
5
       The Commission has adopted modifications to the Part 25 rules to consolidate and
       streamline certain requirements, including the requirement to provide off-axis EIRP
       density plots. See Comprehensive Review of Licensing and Operating Rules for Satellite
       Services, Second Report and Order, 30 FCC Rcd 14713 ¶ 215 (2015) (“Part 25 Second
       Report and Order”). Out of an abundance of caution, ViaSat provides plots in
       accordance with the current Section 25.138(d) requirement, which provides more
       information than in required in the new rules that are not yet in effect.
6
       The Commission has deleted requirement in Section 25.138(e) to provide antenna
       performance plots for the receive bands. See Part 25 Second Report and Order at ¶ 322.
7
       To the extent necessary, and for the same reasons specified in the ViaSat-2
       Authorization, ViaSat requests a waiver of NG165 to allow GSO FSS operations in the
       18.8-19.3 GHz band on a non-conforming basis.
                                               2


harmful interference into NGSO systems as a result of the conditions in the ViaSat-2
Authorization designed to protect NGSO systems in the 18.8-19.3 GHz downlink band segment
and the associated 28.6-29.1 GHz uplink band segment, and as discussed in the ViaSat-2
Modification Application.8

       C.      Terrestrial Operations

        ViaSat will operate in the 27.5-28.35 GHz band segment in a manner that will protect
Local Multipoint Distribution Service (“LMDS”) operations, which are designated in the U.S. as
the primary use of the band, from harmful interference.9 Consistent with the GSO FSS
designation in the United States in this band as secondary with respect to LMDS, as well as the
conditions in the ViaSat-2 Authorization for operations in the 28.1-28.35 GHz band segment and
the commitments that ViaSat has made in the ViaSat-2 Modification Application, ViaSat’s use of
the 27.5-28.35 GHz frequency band for gateway-type earth stations will be on a non-harmful
interference basis relative to LMDS.10 As demonstrated in the attached Technical Analysis, the
proposed earth station is capable of operating on a non-interference basis with existing or future
LMDS stations.11

        In addition, and as demonstrated in the ViaSat-2 Modification Application, which seeks
to add the 17.7-18.3 GHz frequencies, downlinks from ViaSat-2 in this band segment would not
cause harmful interference into fixed service (“FS”) operations that are designated in the U.S. as
primary in this band.12 In that application, ViaSat requested a waiver of the allocations in the


8
       See IBFS File No. SAT-LOI-20130319-00040, Call Sign S2902, at Attach. ¶ 4 (granted
       Dec. 12, 2013); ViaSat-2 Modification Application, Supplemental Technical Annex at
       A.11.
9
       See Rulemaking to Amend Parts 1, 2, 21, and 25 of the Commission’s Rules to
       Redesignate the 27.5-29.5 GHz Frequency Band, to Reallocate the 29.5-30.0 GHz
       Frequency Band, to Establish Rules and Policies for Local Multipoint Distribution
       Service and for Fixed Satellite Services, First Report and Order, FCC 96-311, ¶¶ 42, 44
       (1996) (“28 GHz First Report and Order”) (designating the FSS as secondary to LMDS
       but having “licensing priority vis-a-vis any third service allocated domestically or
       internationally in the band”).
10
       ViaSat-2 Authorization, Attachment ¶ 12 (authorizing ViaSat-2 in the 27.1-28.35 GHz
       band on a secondary basis with respect to LMDS); see also, 28 GHz First Report and
       Order ¶ 45 (“At 27.5-28.35 GHz we designate 850 MHz for LMDS on a primary basis.
       GSO/FSS . . . will be permitted on a non-interference basis to the LMDS systems in the
       850 MHz band segment, for the purpose of providing limited gateway-type services.”).
11
       ViaSat acknowledges the pendency of the Spectrum Frontiers Notice of Proposed
       Rulemaking, which proposes to make this band segment available for terrestrial mobile
       services. See Use of Spectrum Bands Above 24 GHz for Mobile Radio Services, GN
       Docket No. 14-177, Notice of Proposed Rulemaking, FCC 15-138 (rel. Oct. 23, 2015).
       ViaSat would accept a grant conditioned upon the outcome of that proceeding.
12
       See ViaSat-2 Modification Application, Supplemental Technical Annex at A.9.
                                              3


U.S. Table of Frequency Allocations in Section 2.106 of the Commission’s rules. ViaSat
requests a waiver to the extent necessary to allow the proposed earth station antenna to receive
transmissions from ViaSat-2 in this band on a non-protected basis. Downlinks from ViaSat-2 in
this band will meet the power flux density limits prescribed by the ITU, which have been
established to protect terrestrial services in this band. As a non-conforming user, ViaSat would
accept interference from FS operations in this band.

       D.      BSS Feeder Links

        The 17.7-17.8 GHz is allocated to the FSS on a co-primary basis, and footnote US271
limits the allocation to broadcasting-satellite service (“BSS”) feeder links in the Earth-to-space
direction. Therefore, in the ViaSat-2 Modification Application, ViaSat requested a waiver of
Section 2.106 and footnote US271 to allow ViaSat-2 to operate downlinks in this band on a non-
conforming, non-interference basis. In that application, ViaSat demonstrated that ViaSat-2
downlinks in this band would not cause harmful interference into receivers on adjacent BSS
spacecraft.13 Correspondingly, ViaSat requests a waiver in this application to the extent
necessary to permit the proposed earth station to receive transmissions from ViaSat-2 in the
17.7-17.8 GHz band segment. As a non-conforming user, ViaSat would accept interference from
BSS Earth-to-space transmissions into the proposed earth station in this band segment.

II.    RADIATION HAZARD ANALYSIS

        A radiation hazard analysis for the proposed antenna is attached hereto as Exhibit D. As
demonstrated by the results of the analysis, harmful levels will not be present in areas occupied
by the general population, and the antenna does not present a risk to trained personnel in the
controlled area in the immediate vicinity of the antenna.

III.   FAA NOTIFICATION

       The proposed 9.1 meter antenna is exempt from notification to the FAA under Section
17.7(e)(1) of the Commission’s rules because the antenna will be shielded by existing structures
of equal or greater height, and thus will not adversely affect safety in air navigation.




13
       See id. at A.10.
                                                4


                                       Technical Analysis

The Commission’s rules permit GSO FSS use of the 27.5-28.35 GHz band segment on a
secondary basis for gateway-type earth stations on a secondary basis to LMDS facilities. ViaSat
submits the following showing to demonstrate that the proposed gateway-type earth station is
capable of operating on a non-interference basis with existing or future LMDS stations.

ViaSat has implemented measures to ensure that the earth station will operate in a manner that
will protect LMDS stations from harmful interference. ViaSat has located the earth station in an
area where LMDS has not been deployed. In selecting the site, ViaSat relied on both computer
database and RF measurement surveys conducted by Comsearch at the actual earth station
location. The field measurements showed no measurable presence of LMDS activity (see
attached Comsearch report). The Comsearch report includes photographs and maps of the earth
station location. Given the characteristics of the location, LMDS deployment is unlikely in the
future. However, prior to commencement of the proposed operations, ViaSat will notify any
LMDS licensees in the vicinity and provide them with a point of contact with respect to the
operation of this earth station so that they can notify ViaSat should they plan to deploy an LMDS
facility in the vicinity of this earth station in the future. Such notice would allow ViaSat to
protect those LMDS stations by erecting shielding around the earth station.

ViaSat conducted a technical analysis to determine a “worst case” potential required separation
distance from an LMDS terminal, assuming no shielding were employed at the earth station and
no additional blockage from terrain. The operating elevation angle for the earth station is 36.2
degrees, but from the antenna EIRP density plots in Exhibit B it can be seen that the EIRP
density toward the horizon is -40 dBW/40 kHz.

Because no sharing criteria have been expressly adopted, ViaSat relied on research available in
technical papers discussing LMDS systems and link budgets,14 and also obtained LMDS
equipment specifications from a major LMDS equipment manufacturer.15 Based on the available
research, ViaSat selected a ΔT/T of 6% as the basis for calculating the potential separation
distance with no shielding at the earth station. This threshold results in an I/N ratio of -12.2 dB
and yields an effective increase to the LMDS receiver’s noise floor of 0.27 dB. These levels are
not assumed to be, and should not be construed as, the basis for assessing what would constitute
“harmful interference” into the LMDS facility. The ΔT/T of 6% threshold was used in ViaSat’s
analysis demonstrating compatibility of the 17 ViaSat-1 earth stations that operate in the in the
28.1-28.35 GHz band, which were granted based on that analysis.

The analysis considers both hub-type and user-type LMDS terminals. However, the higher
antenna gain and the better receiving performance of the user-type LMDS terminals make these


14
       Robert Duhamel, “Local Multipoint Distribution Service (LMDS) Cell Sizing and
       Availability,” IEEE P802.16 Broadband Wireless Access Working Group (June 9, 1999),
       available at http://wirelessman.org/sysreq/contributions/80216sc-99_17.pdf.
15
       DragonWave Packet Microwave Systems, Product Link:
       http://www.dragonwaveinc.com/products-wireless-ethernet.asp.
                                           1


terminals more sensitive than the hub-type terminals, and thus, more susceptible to interference.
Therefore, only the results of the analysis from the LMDS user terminals are presented here.

The analysis assumes the LMDS terminal has an antenna gain of 31 dBi and a receiver noise
figure of 6 dB, which are included in the technical specifications provided for sample LMDS
equipment. Based on these assumptions, ViaSat calculated the required separation distance
between the earth station and the LMDS terminal under a worst-case alignment scenario. This
calculation assumes that the LMDS user terminal is located along a line on the same bearing as
the satellite and pointed directly at the earth station, i.e., maximal coupling between the two
antennas.

                 Parameters                            ViaSat               LMDS

Frequency (GHz)                                                  28.3              28.3 GHz
On-axis EIRP Density                                            32.99                     dBW/MHz
On-axis Transmit Antenna Gain                                    66.3                     dBi
Off-axis Angle                                                  36.24               0.0 deg
Off-axis Transmit Antenna Gain                                    -6.7                    dBi
Off-Axis EIRP density                                           -40.0                     dBW/MHz
Circular to Linear Polarization Reduction                                           3.0   dB
Distance between sites                                                             6.84   km
Path Loss                                                                        138.2    dB
On-axis Receive Antenna Gain                                                       31.0   dBi
Off-axis Receive Antenna Gain Reduction                                             0.0   dB
System Noise Figure                                                                 6.0   dB
Thermal Noise Density                                                           -138.0    dBW/MHz
Interference Noise Density                                                      -150.2    dBW/MHz
I/N                                                                               -12.2   dB
Noise Floor Degradation                                                         0.2531    dB
ΔT/T                                                                            6.0002    %

Received Carrier Level                                                           -117.0   dBW/MHz
Received Noise Plus Interference                                                 -137.7   dBW/MHz
C/(N+I)                                                                           20.71   dB
Reduction due to Interference Noise                                                0.25   dB

          Table 1 System Parameters and Results for 33.8 Degree Elevation Angle

The results in Table 1 indicate that the required separation distance between an LMDS terminal
and the earth station for the worst case alignment and lowest elevation installation is 6.8 km.
This is the minimum distance along this worst case path between an LMDS terminal and the
earth station that satisfies the above 6% ΔT/T protection criteria without requiring ViaSat to take
measures to mitigate interference into that LMDS terminal. The actual required separation
distance may be smaller depending on the characteristics of the surrounding terrain and
variations in the LMDS system from the assumptions used in this analysis. The required
                                                 2


separation distance decreases dramatically when the LMDS station’s antenna is not pointed
toward the earth station.

ViaSat conducted further analyses using Visualyse software to perform an area analysis that
demonstrates the impact to the area surrounding the earth station when operating at a 36.2 degree
elevation angle, which is operating elevation angle for this earth station. The Visualyse
simulation determines the level of interference into an LMDS user terminal at all locations
surrounding the earth station for a variety of LMDS hub locations. In this area analysis, the
LMDS hub terminal is moved in small steps around a square centered over the earth station such
that the LMDS hub station is located about 2.5 km from the earth station as it moves around the
periphery of the square. Each time the LMDS hub station is moved, the LMDS user terminal is
then moved in small steps to each location within the area and the I/N results are recorded. The
analysis continues in successive iterations until all of the results for the various locations are
recorded. Using these recorded results, Visualyse generated the figure shown below to illustrate
the worst case contour boundary where the interference level from the earth station into the
LMDS user terminal exceeds the assumed 6% ΔT/T threshold. This boundary is indicated by the
green contour line. The red contour lines indicate an I/N of 0 dB (100% ΔT/T). The LMDS user
station in the figure is shown 2.6 km away from the earth station.

Figure 1 depicts the Visualyse results for the scenario described above. Under this scenario, the
results show that the worst case required separation distance is 2.6 km. The grids in the figure
are spaced at 1 km intervals. In this scenario, Visualyse calculates a shorter distance to meet the
6% ΔT/T threshold than Table 1 above. If necessary, shielding could be employed as needed to
reduce the required separation distance toward any higher priority co-frequency terrestrial
deployment.




                                                 3


                    Figure 1 Visualyse Results for Variable Hub Location

Figure 2 shows the same Visualyse simulation for an example static LMDS hub location
approximately 1 km northwest of the earth station site. In this case the LMDS user terminal is
again moved to all locations within the area analysis, but because only the single worst case
antenna alignment occurs, the distance to meet the 6% ΔT/T criteria remains at about 2.1 km, but
the potentially affected area is reduced to a few narrow strips and the remainder of the analysis
area is unaffected.




                                                4


Figure 2 Visualyse Results for Static Hub Location




                        5



Document Created: 1070-04-28 00:00:00
Document Modified: 1070-04-28 00:00:00

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