Attachment BRW Comsearch

This document pretains to SES-DBM-INTR2019-00975 for Database Entry MOD on a Satellite Earth Station filing.


   Transmit/Receive Earth Station

            Prepared For
           Barrow, Alaska

   Transmit/Receive Earth Station

         December 20, 2018

                            TABLE OF CONTENTS

I.     Introduction

II.    Contents of Report

III.   Summary of Results

IV.    Conclusions and Recommendations

V.     Operational Parameters and Satellite Data

VI.    Great Circle Interference Case Listing

                        List of Illustrations

                    Transmit/Receive Earth Station

Figure 5.1-1 Proposed Earth Station Location


Table 5.1-1 Earth Station Parameters

Table 5.2-1 Earth Station Azimuth Elevation Table

                              SECTION 1


                    Transmit/Receive Earth Station

This report presents the results of a detailed interference analysis
for the proposed modifications to the C-band transmit/receive earth
station location. The site was selected by Harris and is located in
Barrow, Alaska (BRW).

The analysis was performed for a 4.5 meter antenna. The long term
interference objective at 4 GHz, was -156 dBW/1 MHz, while the 6 GHz
long term interference objective was -154 dBW/4 kHz, as specified by
the FCC.

The earth station was analyzed for transmission and reception of
digital traffic to and from a satellite arc range of 118 to 150
degrees West Longitude. This report assumes that the satellite
transponders are numbered 1 through 24, with each transponder having a
36 MHz bandwidth.

This detailed interference analysis is meant to provide an estimate of
potential interference at this location, and to recommend a course of
future action.

                              SECTION 2


                    Transmit/Receive Earth Station

This section describes the contents of     the   report   for   a   proposed
C-band transmit/receive earth station.

Section   1 describes the site location, the antenna considered, and
the system parameters considered in the detailed interference
analysis. The analysis was undertaken to determine the potential for
microwave interference for the transmit/receive earth station at the
site specified.

Initially, a computer analysis of this site was performed to determine
the extent of potential interference on a line-of-sight (LOS) basis.
This analysis considers the microwave environment with respect to the
earth station and calculates predicted signal levels     between these
systems. Paths which exceed a given objective level are listed for
further analysis. The objective levels present the             maximum
interference levels allowed between the earth station and          the
surrounding terrestrial microwave environment for the frequency band
of interest.

To further analyze the effect of the predicted interference conflicts,
terrain path profiles were prepared for the critical       cases. This
involves plotting the interference path on topographic maps, typically
7.5 minute series U.S.G.S. maps, to determine the               terrain
characteristics of the path. Once this has been accomplished,
predicted over-the-horizon (O-H) losses are      calculated using the
techniques of the National Bureau of Standards     Technical Note 101

These calculations give the amount of signal attenuation achieved       due
to terrain blockage.

Section 3 summarizes the results of the site analysis. This   summary
includes the number of cases that were considered, the   interference
cases that remain, and the proposed resolution of   the interference

Tables 3.1-1 and 3.2-1 list the Great Circle interference cases and
the predicted O-H losses calculated on the various 6 and 4 GHz paths,
respectively. If multiple analyses are considered, such as changes in
satellite arc or antenna, the results are presented in Tables 3.1-1.1,
3.1-1.2, 3.2-1.1 3.2-1.2, etc.....

A brief explanation of the various columns shown in Tables 3.1-1               and
3.2-1 follows:

PATH   ID:    This   is the predicted interference path.    The   first
site listed is the transmitter at 4 GHz or the receiver at 6 GHz.

BAND:   This shows the frequency plan of the interfering paths. The 4
GHz paths affect reception of the downlink, while the 6 GHz
terrestrial facilities are affected by the uplink.    Receivers in the
low half of the band (5925 - 6175 MHz), are indicated by 6L.

Receivers in the   high   half   of   the   band   (6175   -   6425    MHz),   are
indicated by 6H.

DIST: This is the distance from the earth station to the              terrestrial
station in kilometers.

AZ: This is the azimuth bearing in degrees (taken from True               North),
from the earth station toward the terrestrial station.

ES DISC: This is the earth station discrimination angle in               degrees,
towards the involved terrestrial facility.

ES GAIN: This is the gain of the earth station in dBi, at the
calculated earth station discrimination angle.

LOS LOSS REQ'D: This is the amount of loss required in dB, on                    a
line-of-sight basis, to meet the interference objective.

O-H   LOSS:  This is the calculated over-the-horizon (O-H) losses in
dB, between the earth station and the involved terrestrial station.
The 20 percent column represents losses for the long term objective.
The 0.0025 and .01 percent columns present the losses for the short
term objective at 6 GHz and 4 GHz, respectively.

REVISED   MARGIN:   This is the difference between the LOS margin and
the predicted     O-H   losses   achieved due to terrain      blockage.
Sufficient attenuation is calculated for the paths which show the word
"CLEAR" in the revised margin. Cases showing a positive revised margin
will require additional losses to meet the interference objective.

The information listed at the bottom of the table reflects the
antennas, satellite arc, and interference objectives considered for
the proposed site.

Section   4  presents   conclusions and recommendations. It   gives
an overall description of the microwave environment and suggests a
future course of action.

Table 5.1-1 contains     the operational parameters for the      proposed
earth station. Tables    5.1-2 provides azimuth and elevation data for
the geostationary arc,   and identifies the locations of particular
satellites within that   arc.

Figure 5.1-1 indicates the location of the site analyzed. This
location should be verified. If it is not the desired site, Comsearch
should be notified immediately so that the precise location can be

Section 6 presents the Great Circle interference cases. This provides
a listing of the utilized channels and type of traffic loading for
each path.

                             SECTION 3

                        SUMMARY AND RESULTS

The detailed interference analysis for the proposed modifications to
the earth station site located in Barrow (BRW), Alaska revealed that
no potential interference conflicts exist within the coordination
contours of the proposed earth station site.

                              SECTION 4


4.1   Conclusions

Based on the results of the detailed interference analysis, no
potential interference conflicts exist within the coordination
contours of this earth station site.

4.2   Recommendations

It is recommended that Harris/FAA review the operating parameters of
the proposed earth station antenna and then proceed with the frequency
coordination modification of this earth station site.

                                  Table 5.1-1

                              SATELLITE EARTH STATION
                            FREQUENCY COORDINATION DATA

Company                    Federal Aviation Administration
Owner Code                                       FEDFAA
Earth Station Name, State                        BARROW, AK
Latitude (DMS) (NAD83)                           71 16 56.8 N
Longitude (DMS) (NAD83)                          156 47 30.5 W
Ground Elevation AMSL (ft/m)                       19.36 /     5.90
Antenna Centerline AGL (ft/m)                       9.00 /     2.74

Receive Antenna Type:           FCC32                  Scientific-Atlanta

            4.0 GHz Gain (dBi) / Diameter (m)            43.3 /         4.5
              3 dB / 15 dB Half Beamwidth                0.60 /         1.25

Transmit Antenna Type:          FCC32                  Scientific-Atlanta

            6.0 GHz Gain (dBi) / Diameter (m)            46.3 /         4.5
              3 dB / 15 dB Half Beamwidth                0.39 /         0.81

Operating Mode                                         TRANSMIT AND RECEIVE
Modulation                                             DIGITAL
Emission / Receive Band (MHz)           451KG7D   1M05G7D / 3700.0000 - 4200.0000

Emission / Transmit Band (MHz)          451KG7D   1M05G7D /       5925.0000 -   6425.0000

Max. Available RF Power (dBW)/4 kHz)                     -13.30
                        (dBW)/MHz)                        10.70

Max. EIRP                 (dBW)/4 kHz)                    33.00
                          (dBW)/MHz)                      57.00
                          (dBW)                            0.00

Max. Permissible Interference Power
           4.0 GHz, 20% (dBW/1 MHz)                     -156.0
           4.0 GHz, 0.0100% (dBW/1 MHz)                 -146.0
           6.0 GHz, 20% (dBW/4 kHz)                     -154.0
           6.0 GHz, 0.0025% (dBW/4 kHz)                 -131.0

Range of Satellite Arc (Geostationary)
Degrees Longitude                                      115.0 W / 150.0 W
Azimuth Range (Min/Max)                                  136.7 / 172.8
Corresponding Elevation Angles                             5.2 / 10.0

Radio Climate                                                 B
Rain Zone                                                     2

Max. Great Circle Coordination Distance (mi./km)
           4.0 GHz                                       493.1 /       793.5
           6.0 GHz                                       169.4 /       272.6

Precipitation Scatter Contour Radius (mi./km)
           4.0 GHz                                       382.8 /       616.1
           6.0 GHz                                        62.1 /       100.0

                     Earth Station Azimuth and Elevation Table

Earth Station Name      BARROW, AK
Owner                   Federal Aviation Administration
Latitude (DMS) (NAD83) 71 16 56.8 N
Longitude (DMS) (NAD83) 156 47 30.5 W
Ground Elevation (ft/m)        19.36 /    5.90 Amsl
Antenna Centerline (ft/m)       9.00 /    2.74 Agl
Satellite Arc Range       115.0 W
                          150.0 W

    Satellite    Azimuth    Elevation   Satellite
    Longitude   (Degrees)   (Degrees)     Name

      115.0        136.7         5.2     XM 4
      116.0        137.7         5.4
      116.8        138.5         5.6     SATMEX 5
      117.0        138.7         5.6
      118.0        139.7         5.8
      119.0        140.7         6.0
      120.0        141.7         6.2
      121.0        142.7         6.4     GALAXY 23
      121.0        142.7         6.4     ECHOSTAR 9
      122.0        143.7         6.6
      123.0        144.8         6.8     GALAXY 10R
      124.0        145.8         7.0
      125.0        146.8         7.2     GALAXY 14
      126.0        147.8         7.4
      127.0        148.9         7.5     GALAXY 13
      127.0        148.9         7.5     HORIZONS 1
      128.0        149.9         7.7
      129.0        150.9         7.9     GALAXY 27
      130.0        151.9         8.0
      131.0        153.0         8.2     AMC 11
      132.0        154.0         8.3
      133.0        155.0         8.5     GALAXY 15
      134.0        156.1         8.6
      135.0        157.1         8.7     AMC 10
      136.0        158.2         8.9
      137.0        159.2         9.0     AMC 7
      138.0        160.2         9.1
      139.0        161.3         9.2     AMC 8
      140.0        162.3         9.3
      141.0        163.4         9.4
      142.0        164.4         9.5
      143.0        165.5         9.6
      144.0        166.5         9.7
      145.0        167.6         9.7
      146.0        168.6         9.8
      147.0        169.7         9.9
      148.0        170.7         9.9
      149.0        171.8        10.0
      150.0        172.8        10.0

Figure 5.1-1

Document Created: 2018-12-20 11:36:05
Document Modified: 2018-12-20 11:36:05

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