Attachment SESLIC2017072500795S

SESLIC2017072500795S

SUPPLEMENT submitted by SES AMERICOM, INC.

13 GHZ STUDY

2017-08-07

This document pretains to SES-LIC-20170725-00795 for License on a Satellite Earth Station filing.

IBFS_SESLIC2017072500795_1258911

                                                Exhibit For
                                           SES Americom, LLC
                                           Woodbine, Maryland
                                     ASC Signal 7.6 Meter Earth Station

     Compliance with FCC Report & Order (FCC96-377) for the 13.75 - 14.0 GHz Band
                              Analysis and Calculations

1.           Background

This Exhibit is presented to demonstrate the extent to which the SES Americom, LLC satellite
earth station in Woodbine, Maryland is in compliance with FCC REPORT & ORDER 96-377.
The potential interference from the earth station to US Navy shipboard radiolocation operations
(RADAR) and the NASA space research activities in the 13.75 - 14.0 GHz Band is addressed in
this exhibit. The parameters for the earth station are:

                              Table 1. Earth Station Characteristics

     •       Coordinates (NAD83):                     39° 22’ 38.8” N, 77° 04’ 52.0” W

     •       Satellite Location for Earth Station:    10° W to 145° W


     •       Frequency Band:                           13.75-14.0 GHz for uplink

     •       Polarizations:                            Horizontal and Vertical

     •       Emissions:                                745KG7W, 38M8G7W and 72M0G7W

     •       Modulation:                               Digital

     •       Maximum Aggregate Uplink EIRP:           68.0 dBW for the 745 kHz Carriers
                                                      85.0 dBW for the 38.8 MHz Carriers
                                                      85.0 dBW for the 72 MHz Carriers

     •       Transmit Antenna Characteristics
                Antenna Size:                          7.6 meters in Diameter
                Antenna Type/Model:                    ASC Signal
                Gain:                                  59.3 dBi


         •    RF power into Antenna Flange             745 kHz
                                               -        8.7 dBW
                                                        or -14.0 dBW/4 kHz


              (Continued)                            38.8 MHz
                                                     25.7 dBW
                                                     or –14.2 dBW/4 kHz (Maximum)

                                                     72 MHz
                                                     25.7 dBW
                                                     or –16.8 dBW/4 kHz (Maximum)

     •   Minimum Elevation Angle:
          Woodbine, Md                               8.9° @ 105.0° - 8.3° @ 255.6°


     •   Side Lobe Antenna Gain:                     32 - 25*log(θ)


Because the above uplink spectrum is shared with the Federal Government, coordination in this
band requires resolution data pertaining to potential interference between the earth station and
both Navy Department and NASA systems. Potential interference from the earth station could
impact with the Navy and/or NASA systems in two areas. These areas are noted in FCC Report
and Order 96-377 dated September 1996, and consist of (1) Radiolocation and radio navigation,
(2) Data Relay Satellites.

Summary of Coordination Issues:

1) Potential Impact to Government Radiolocation (Shipboard Radar)
2) Potential Impact to NASA Data Relay Satellite Systems (TDRSS)

2.       Potential Impact to Government Radiolocation (Shipboard Radar)

Radiolocation operations (RADAR) may occur anywhere in the 13.4 - 14 GHz frequency band
aboard ocean going United States Navy ships. The Federal Communication Commission (FCC)
order 96-377 allocates the top 250 MHz of this 600 MHz band to the Fixed Satellite Service
(FSS) on a co-primary basis with the radiolocation operations and provides for an interference
protection level of -167 dBW/m2/4 kHz.


The closest distance to the shoreline from the Woodbine earth station is approximately 65.9 km
Southeast toward the Chesapeake Bay. The calculation of the power spectral density at this
distance is given by:
                                          745 kHz       38.8 MHz      72 MHz

         1.    Clear Sky EIRP (dBW):        68.0          85.0         85.0
         2.    Carrier Bandwidth:          745 kHz       38.8 MHz     72 MHz
         3.    PD at antenna Input:       -14.0          -14.2        -16.8
               (dBW/4 kHz)
         4.    Transmit Antenna Gain:                        59.3 dBi
         5.    Antenna Gain Horizon:                     FCC Reference Pattern
         6.    Antenna Elevation Angle:                      8.3°


The proposed earth station will radiate interference toward the Chesapeake Bay according to its
off-axis side-lobe performance. A conservative analysis, using FCC standard reference pattern,
results in off-axis antenna gains of 8.8 dBi toward the Chesapeake Bay.

The signal density at the shoreline, through free space is:

745 kHz Carriers
PFD = Antenna Feed Power density (dBW/4 kHz) + Antenna Off-Axis Gain (dBi) – Spread Loss
(dBw-m2).

       = -14.0 dBw/4 kHz + (8.8) dBi – 10*log[4Π*(65900m)2]
       = -112.6 dBW/m2/4 kHz + Additional Path Losses (~63.0 dB)
       = -175.6 dBW/m2/4 kHz

38.8 MHz Carriers
PFD = Antenna Feed Power density (dBW/4 kHz) + Antenna Off-Axis Gain (dBi) – Spread Loss
(dBw-m2).

       = -14.2 dBw/4 kHz + (8.8) dBi – 10*log[4Π*(65900m)2]
       = -112.7 dBW/m2/4 kHz + Additional Path Losses (~63.0 dB)
       = -175.7 dBW/m2/4 kHz

72 MHz Carriers
PFD = Antenna Feed Power density (dBW/4 kHz) + Antenna Off-Axis Gain (dBi) – Spread Loss
(dBw-m2).
      = -16.8 dBw/4 kHz + (8.8) dBi – 10*log[4Π*(65900m)2]
      = -115.4 dBW/m2/4 kHz + Additional Path Losses (~63.0 dB)
      = -178.4 dBW/m2/4 kHz

Our calculations identified additional path losses of approximately 63.0 dB including absorption
loss and earth diffraction loss for the actual path profiles from the earth station to the nearest
shoreline.

The worst case calculated PFD including additional path losses to the closest shoreline location is
–175.6 dBW/m2/4 kHz for the 745 kHz carriers and -175.7 dBW/m2/4 kHz for the 38.8 MHz
carriers and -178.4 dBW/m2/4 kHz for the 72 MHz. All carriers are a minimum of 8.6 dB below
the –167 dBW/m2/4 kHz interference criteria of R&O 96-377. Therefore, there should be no
interference to the US Navy RADAR from the Woodbine earth station due to the distance and the
terrain blockage between the site and the shore.


3.     Potential Impact to NASA’s Data Relay Satellite System (TDRSS)

The geographic location of the SES Americom earth station in Woodbine, Maryland is outside the
390 km radius coordination contour surrounding NASA’s White Sands, New Mexico ground
station complex. Therefore, the TDRSS space-to-earth link will not be impacted by the SES
Americom earth station in Woodbine, Maryland.

The TDRSS space-to-space link in the 13.772 to 13.778 GHz band is assumed to be protected if
an earth station produces an EIRP less than 71 dBW/6 MHz in this band. The 7.6 meter earth
station antenna will have an EIRP less than 71 dBW/6 MHz for the 745 kHz carriers in this band.
The total EIRP for the 745 kHz, carriers is 68.0 dBW. The equivalent EIRP per 6 MHz segment
will remain at 68.0 dBW/6 MHz. For the 38.8 MHz and 72 MHz carriers, the total EIRP of 85.0
dBW (38.8 MHz), and 85.0 dBW (72 MHz) equate to an EIRP per 6 MHz of 78.5 dBW/6 MHz
and 73.0 dBW/6 MHz, respectively. To avoid interference to the TDRSS space-to-space link the
38.8 MHz and 72 MHz carriers will not be used for the transmit spectrum of 13.772 to 13.778
GHz by this earth station.

4.   Coordination Issue Result Summary and Conclusions

The results of the analysis and calculations performed in this exhibit indicate that compatible
operation between the earth station at the Woodbine facility and the US Navy and NASA systems
space-to-earth link are possible for all of the proposed carriers. Operations in NASA systems
space-to-space link (13772.0 to 13778.0 MHz) will also be permitted for all of the carriers with
the exception of the 38.8 MHz and 72 MHz emissions.



Document Created: 2017-08-07 17:56:58
Document Modified: 2017-08-07 17:56:58

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