Attachment BRW Comsearch SES-DBM-20190403-00482

Attachment BRW Comsearch

This document pretains to SES-DBM-20190403-00482 for Database Entry MOD on a Satellite Earth Station filing.

IBFS_SESDBM2019040300482_1635312

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

Tables

Table 5.1-1 Earth Station Parameters

Table 5.2-1 Earth Station Azimuth Elevation Table

SECTION 1

INTRODUCTION

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

REPORT CONTENTS AND PROCEDURES

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
(Revised).

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
problems.

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
analyzed.

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

CONCLUSIONS AND RECOMMENDATIONS

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
12/20/2018

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
12/20/2018

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

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

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