Redacted Technical Annex

0353-EX-CN-2018 Text Documents

PointView Tech LLC

2018-04-26ELS_208690

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                              ATHENA NGSO SATELLITE


                                          EXHIBIT 1
      Technical Information to Supplement Form 442 and Application
                                           Narrative



A.1    Scope and Purpose


This exhibit supplements FCC Form 442 and contains the technical information referenced in the
application narrative that is required by Parts 5 and 25 of the Commission’s rules.
A.2    Radio Frequency Plan (§25.114(c)(4))


The Athena satellite will have two E-band uplinks and two E-band downlinks. The downlink
emissions are nominally centered at 72 GHz and 75 GHz and the uplink emissions are nominally
centered at 82 GHz and 85 GHz1. The bandwidth for both the uplinks and downlinks is 2.1852
GHz. The TT&C uplink will be conducted at 2082 MHz with an occupied bandwidth of 1.5
MHz. The TT&C downlink will be conducted at 8496.25 MHz with an occupied bandwidth of
2.3 MHz. Table A.2-1 shows the frequency ranges to be used by the Athena satellite.




1
  There is the possibility that mild tuning may be performed from the planned 72, 75, 82 and 85
GHz centered carriers (e.g., 74.8 and 82.2 GHz may be used for example to mitigate any
potential, mild “inter-channel interference” due to spectral regrowth issues and limited transmit-
to-receive isolation). In addition, a limited number of tests, estimated at one to two dozen, may
be performed with continuous wave (CW), unmodulated carriers as far out as the band edges
(i.e., 71-76 GHz and 81-82 GHz) to measure the atmospheric attenuation characteristics. Any
mild tuning or atmospheric measurement testing would maintain compliance with NTIA
Redbook requirements for the licensed carriers.


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              Table A.2-1: Frequency Bands Used by the Athena non-GSO Satellite

               Type of Link and Transmission Direction       Frequency Ranges

                                                         80.9074 – 83.0926 GHz
               E-band Uplink
                                                         83.9074 – 86.0926 GHz

                                                         70.9074 – 73.0926 GHz
               E-band Downlink
                                                         73.9074 – 76.0926 GHz

               TT&C Uplink                               2081.25 – 2082.75 MHz

               TT&C Downlink                             8494.75 – 8497.75 MHz



The E-band uplink and E-band downlink will use both right-hand circular polarization and left-
hand circular polarization. The TT&C uplink and TT&C downlink will use right-hand circular
polarization.

A.3    Non-GSO Orbital Characteristics (§25.114(c)(6))


The Athena experiment will consist of one non-GSO satellite operating in a circular sun-
synchronous orbit at an altitude of 500 to 550 km. Table A.3-1 gives the other relevant orbital
parameters for the Athena satellite.




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                              Table A.3-1: Athena Satellite Characteristics

         Number of Orbital Planes                      1

         Satellites Per Orbital Plane                  1

                                                       97.4° for 500 km case
         Inclination of the Orbital Plane
                                                       97.6° for 550 km case

                                                       5677 seconds (1 hour, 34.6 minutes) for
                                                       500 km case
         Orbital Period
                                                       5730 seconds (1 hour, 35.5 minutes) for
                                                       550 km case

         Apogee                                        500 – 550 km

         Perigee                                       500 – 550 km

                                                       When visible to the earth stations at
         Active Service Arc                            minimum elevation angles of 5° - 30°
                                                       (See Section A.4 for further explanation)

         Local Time of Descending Node                 10:30 AM


It is noted that additional orbital parameters, such as the argument of perigee and the initial phase
angle of the satellite, are not applicable to a one-satellite non-GSO system in a circular orbit.
The right ascension of the ascending node (RAAN) is dependent upon the specific launch date.
The RAAN will change by 0.9856° per day in order to keep up with the 360° Earth rotation
around the sun in 365.25 days.


A.4    Frequency Bands and Coverage Areas (§25.114(c)(7))


As stated in Section A.2, the E-band downlinks will be in the 70.9074-76.0926 GHz frequency
ranges and the E-band uplinks will be in the 80.9074-86.0926 GHz frequency ranges. During
nominal operations, the satellite will only transmit and receive in the E-band when it is at an
elevation angle greater than or equal to 30° from one of the earth stations located in the Los
Angeles/Ventura county area. However, there may be some experiments in which the satellite
will transmit and receive in the E-band when it is at a minimum elevation angle of 10°.

TT&C will be performed in the 2081.25-2082.75 MHz frequency band for the uplink and the
8494.75-8497.75 MHz band for the downlink. For TT&C, the satellite will only transmit and
receive when it is at an elevation angle greater than or equal to 5° from the Mojave, Brewster and

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Albuquerque earth stations. Figures A.4-1 and A.4-2 show the coverage areas for the TT&C
links based on these minimum elevation angles. The spacecraft will only transmit and receive
when it is within the yellow circles on the figures. The grid shows 15° lines for both latitude and
longitude.

               Figure A.4-1: Global View of Athena Satellite TT&C Coverage Area




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               Figure A.4-2: Zoom View of Athena Satellite TT&C Coverage Area




Figure A.4-3 and Figure A.4-4 show the coverage areas of the Athena satellite E-band for
minimum elevation angles of 30° and 10°, respectively. The spacecraft will only transmit and
receive when it is within the green circles on the figures. The grid shows 15° lines for both
latitude and longitude.




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Figure A.4-3: View of Athena Satellite E-Band Coverage Area for 30° Minimum Elevation Angle




Figure A.4-4: View of Athena Satellite E-Band Coverage Area for 10° Minimum Elevation Angle




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A.5    Calculated Maximum Power Flux Density Levels (§25.114(c)(8))

The Athena satellite’s TT&C downlink operations in part of the 8025-8500 MHz band comply
with the ITU Power Flux Density (“PFD”) limits applicable to that band. Table A.5-1 shows the
ITU PFD limits in the band.


           Table A.5-1: ITU Power Flux Density Limits in the 8025 – 8500 MHz Band

                                    PFD Limit in dB(W/m2) for angles
                                 of arrival (δ) above the horizontal plane       Reference
        Frequency range
                                                                                 bandwidth
                              0°-5°               5°-25°               25°-90°
       8025 – 8500 MHz        -150          −150 + 0.5(δ − 5)           −140       4 kHz

The Athena satellite TT&C downlink has a maximum transmit EIRP of 3.64 dBW and a
bandwidth of 2.3 MHz. Table A.5-2 shows the maximum PFD at the surface of the earth produced
by this emission assuming an orbital altitude of 500 km, which would result in the highest PFD
levels.


               Table A.5-2: Maximum Athena PFD in the 8025 – 8500 MHz Band

                          Maximum EIRP (dBW)                         3.64
                          Bandwidth (MHz)                             2.3
                          EIRP Density (dBW/4 kHz)                  -23.94
                          Minimum Distance (km)                      500
                          Maximum PFD (dBW/m2/4 kHz)               -148.96


Table A.5-3 shows the calculated maximum PFD levels at the surface of the Earth for elevation
angles from 5° to 90° along with the margin and demonstrates that the ITU PFD Limit in the 8025-
8500 MHz band is met. Figure A.5-1 shows the graphical comparison of the Athena maximum
PFD levels to the ITU PFD limits.




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 Table A.5-3: X-Band TT&C Downlink Compliance with ITU PFD Limits in the 8025-8500 MHz
                                       Band
                                                PFD with Peak
                                                Antenna Gain    Margin to
              Elevation    ITU PFD Limit          (dBW/m2 /     ITU PFD
              Angle (°)   (dBW/m2 / 4kHz)            4kHz)      Limit (dB)
                  5           -150.00               -160.78       10.78
                 10           -147.50               -159.31       11.81
                 15           -145.00               -157.70       12.70
                 20           -142.50               -156.26       13.76
                 25           -140.00               -155.00       15.00
                 30           -140.00               -153.91       13.91
                 35           -140.00               -152.95       12.95
                 40           -140.00               -152.13       12.13
                 45           -140.00               -151.65       11.65
                 50           -140.00               -151.04       11.04
                 55           -140.00               -150.52       10.52
                 60           -140.00               -150.09       10.09
                 65           -140.00               -149.73        9.73
                 70           -140.00               -149.44        9.44
                 75           -140.00               -149.22        9.22
                 80           -140.00               -149.06        9.06
                 85           -140.00               -148.97        8.97
                 90           -140.00               -148.96        8.96




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        Figure A.5-1: PFD Levels from the Athena TT&C Downlink compared with ITU Limits


                      -135




                      -140




                      -145
 PFD (dBW/m2/4 kHz)




                      -150




                                                               ITU PFD Limits
                      -155
                                                               Calculated Athena PFD




                      -160




                      -165
                             0   10   20   30       40            50            60     70   80   90
                                                Elevation Angle (degrees)




There are no ITU or FCC PFD limits in the 71-76 GHz band. In this band, the Athena satellite has
a maximum transmitted EIRP of 44.3 dBW and a bandwidth of 2.1852 GHz. Table A.5-4 shows
the maximum PFD at the surface of the earth produced by this emission. Table A.5-5 shows the
calculated maximum PFD levels for elevation angles from 10° to 90°.




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 Table A.5-4: Maximum Athena Satellite PFD at the Surface of the Earth in the 71 - 76 GHz Band

                         Maximum EIRP (dBW)                       44.3
                         Bandwidth (GHz)                         2.1852
                         EIRP Density (dBW/4 kHz)               -113.07
                         Minimum Distance (km)                    500
                         Maximum PFD (dBW/m2/4 kHz)             -138.05




      Table A.5-5: Maximum Athena PFD in the 71 - 76 GHz Band at Various Elevation Angles

                              Elevation     PFD with Peak Antenna Gain
                              Angle (°)         (dBW/m2/4 kHz)
                                 10                   -148.65
                                 15                   -147.04
                                 20                   -145.60
                                 25                   -144.34
                                 30                   -143.24
                                 35                   -142.29
                                 40                   -141.47
                                 45                   -140.76
                                 50                   -140.15
                                 55                   -139.63
                                 60                   -139.19
                                 65                   -138.83
                                 70                   -138.54
                                 75                   -138.32
                                 80                   -138.17
                                 85                   -138.08
                                 90                   -138.05



5.a     X-Band TT&C Compliance with Deep Space Protection Limits

According to the ITU Radio Regulations, the 8400-8450 MHz band is allocated to the Space
Research Service in the space-to-Earth direction and the use of the band is limited to satellites that
are orbiting in deep space. Recommendation ITU-R SA.1157-1 (“Protection criteria for deep-
space research”) gives the maximum allowable interference power into deep-space receiving earth
stations and the interference protection criteria for deep-space earth stations in the 8400-8425 GHz
frequency band. The following is an excerpt from the ITU-R Recommendation:
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                         Recommendation ITU-R SA.1157-1 TABLE 4
               Maximum allowable interference power to earth-station receivers
                                                                                  Maximum noise-like
                           Receiver noise spectral          Maximum CW
         Band                                                                     interference power
                                  density                 interference power
        (GHz)                                                                       spectral density
                                (dB(W/Hz))                      (dBW)
                                                                                      (dB(W/Hz))
       2.29-2.30                   –216.6                      –221.6                   –222.5
       8.40-8.45.                  –215.0                      –220.0                   –220.9
      12.75-13.25                  –214.6                      –219.6                   –220.5
       31.8-32.3                   –211.4                      –216.4                   –217.3


Protection criteria for deep-space earth-station receivers


Table 5 gives the maximum allowable interference that will not cause more than the acceptable
degradation of earth-station receiver performance. These values are the protection criteria for a
deep-space earth-station receiver at the receiver input terminals: greater interference is harmful.
Also shown is the corresponding power spectral flux-density at the aperture of a 70 m diameter
reflector antenna. The antenna has approximately 70% area efficiency for the lower bands and
40% at 32 GHz.

                         Recommendation ITU-R SA.1157-1 TABLE 5
                     Interference protection for deep-space earth-stations
                     Maximum allowable interference power       Maximum allowable interference power
        Band
                              spectral density                         spectral flux-density
       (GHz)
                                 (dB(W/Hz))                              (dB(W/m2 · Hz))
      2.29-2.30                      –222.5                                    –257.0
      8.40-8.45                      –220.9                                    –255.1
     12.75-13.25                     –220.5                                    –254.3
      31.8-32.3                      –217.3                                    –249.3

To protect earth-station receivers, the power spectral density of noise-like interference, or the
total power of CW interference, should not be greater than the amount shown in Table 5.
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The Athena satellite X-band telemetry carrier is centered at a frequency of 8496.25 MHz. Tests
were performed to determine the interference levels that would be received at a deep-space earth
station operating in the 8400-8450 MHz band. Table A.5.a-1 shows the maximum power level at
the surface of the earth under clear-sky conditions at the Athena satellite TT&C center frequency.

     Table A.5.a-1: Maximum Power Level at the Surface of the Earth at TT&C Center
                                             Frequency


Telemetry (Downlink) Budget
                                  5 deg El       10 deg El      45 deg El     90 deg El
Parameter                         (Peak)         (Peak)         (Peak)        (Peak)    Unit
Frequency                              8.49625        8.49625        8.49625 8.49625 GHz
Altitude                                     500           500            500       500 km
Elevation Angle                                5             10            45        90 deg
Slant Range                            2077.96        1695.09          683.09    500.00 km
Range Factor                             137.34         135.58         127.68    124.97 dB
Aperture Factor                            40.03         40.03          40.03     40.03 dB
Path Loss                               -177.38       -175.61        -167.72 -165.01 dB
Atmospheric Loss                            -0.6           -0.3         -0.07     -0.05 dB

Tx Power                                    2.5            2.5          2.5        2.5 W
                         in dBW            3.98           3.98         3.98       3.98 dBW
S/C Antenna Gain                            5.5            5.5          5.5        5.5 dBi
Tx Loss                                   -5.84          -5.84        -5.84      -5.84 dB
Transmit EIRP                              3.64           3.64         3.64       3.64 dBW
 Transmit EIRP (W)                         2.31           2.31         2.31       2.31 W
Pol Loss                                      0              0            0          0 dB
Power at E/S                            -174.34        -172.27      -164.15    -161.42 dBW


Figure A.5.a-1 shows the test data for the X-band TT&C spurious emissions spectrum down to
8.44 GHz.




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         Figure A.5.a-1: X-band Telemetry Spurious Emissions Spectrum




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As shown in Table A.5.a-1, the power level at the Earth’s surface at 8496.25 MHz is -164.1 dBW.
The CW interference level roll-off from the modulated spectrum peak at the edge of the deep-space
band (8450 MHz) is 67 dBc. Thus, the maximum CW interference power in the deep-space band
is -228.4 dBW, which is 8.4 dB below the maximum CW interference power given in Table 4 of
ITU Recommendation SA.1157-1. The peak PFD at the Earth’s surface of the Athena satellite X-
band downlinks is -185.0 dBW/m2/Hz. The measurements show the test equipment noise floor at
-82 dBc, which results in a PFD in the deep-space band of -267 dBW/m2/Hz, which is 11.9 dBW
less than the protection level given in the ITU Recommendation. Similarly, the noise-like
interference based on a peak power spectral density of -225.0 dBW/Hz and a noise floor of -82
dBc results in a maximum noise-like interference of -307.0 dBW/Hz, which is 86.1 dB less than
the protection values given in the ITU Recommendation. Table A.5.a-2 shows that that Athena
satellite X-band downlinks are compliant with the deep-space protection criteria.

       Table A.5.a-2: Athena Satellite Compliance with Deep Space Protection Criteria




A.6     Overall Description of System Facilities, Operations and Services (§25.114(d)(1))


The Athena experiment includes one non-GSO satellite operating in the E-band (71-76 GHz for
downlink and 81-86 GHz for uplink) communicating with earth stations located in the southwest
United States. The TT&C for the satellite will be conducted in the X-band for downlink and S-
band for uplink and will use three specific earth stations.
Due to the nature of the non-geostationary orbit, there will be limited time during the orbit that
the satellite is visible to one of its earth stations. Additionally, the duration of this visibility will
be relatively short. For the E-band communications, the transmissions will be for less than 8
minutes per contact and there will be up to two contacts per day at an elevation angle greater
than or equal to 30°, which may increase to four contacts a day for experiments at an angle lower
than 30° and greater than or equal to 10°. For the TT&C communications, the transmissions will
be less than 10 minutes per contact. There will be up to ten contacts per day for the TT&C
downlinks, and up to three contacts per day for the TT&C uplinks. The TT&C coverage areas
are shown in Section A.4 of this Exhibit.



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Table A.6-1 gives the maximum amount of time (in seconds) the Athena satellite will transmit
and receive above a given minimum elevation angle during the longest pass over the TT&C and
E-band ground stations.

E-band link “baseline” testing will nominally occur above 30° minimum elevation angles, with
the primary goal of demonstrating high rate links up to 4.5 minutes in duration, per contact, to an
earth station through a variety of atmospheric conditions, enabling the validation of ITU models.
E-band “goal” testing will occur above 20° minimum elevation angles for up to 5.3 minutes to
study the effects of additional atmospheric attenuation. E-band “stretch” testing will occur above
10° minimum elevation angles for up to 8.0 minutes to study maximum attenuation effects. Less
than six contacts per month are planned to be goal or stretch tests that apply minimum elevation
angles less than 30°.

 Table A.6-1: Maximum Pass Time (in Seconds) for Different Minimum Elevation Angles
 Minimum      Maximum Pass      Maximum Pass                        Notes
 Elevation     Time 500 km        Time 550km
  Angle          altitude           altitude
    5°            552.4              589.6               TT&C: Brewster, Mojave,
                                                                Albuquerque
    10 °          443.0              476.9            E-band (stretch test): LA/Ventura
                                                            Counties (see A.6.a)
    20 °          295.8              322.2             E-band (goal test): LA/Ventura
                                                            Counties (see A.6.a)
    30 °          207.4              227.3           E-band (baseline test): LA/Ventura
                                                            Counties (see A.6.a)


A.6.a Description of Satellite, including Antenna Patterns for both E-band and TT&C
For the TT&C, there is a single S/X-band transceiver on the satellite with internal transmit signal
amplification. The receiver is always ON; the transmitter is only ON when in the field-of-view
of the TT&C ground stations above the respective minimum elevation angles. There are two
receive S-band patch antennas for command and two transmit X-band patch antennas for
telemetry. Both command and telemetry use right-hand circular polarization. The gain patterns
for these antennas are given in Figure A.6.a-1 and A.6.a-2. Table A.6.a-1 provides a description
of each of the TT&C earth stations.




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           Figure A.6.a-1 TT&C Satellite Antenna Transmit Pattern




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                    Figure A.6.a-2 TT&C Satellite Antenna Receive Pattern




                        Table A.6.a-1 Description of TT&C Earth Stations
Location                       Mojave, CA              Albuquerque, NM         Brewster, WA
Latitude (°N)                    35.064                     35.054                 48.145
Longitude (°E)                  -118.162                    -106.619               -119.7
Antenna Size               3.0 m (Rx/Tx S-band,        3.0 m S-band Rx/Tx       7.6m (Rx/Tx)
                                Rx X-band)
                                                        4.5m X-band Tx

Maximum Uplink EIRP              45 dBW                     45 dBW                 48 dBW
Earth Station Antenna            34 dBi                      34 dBi               42.2 dBi
Maximum Transmit
Gain
Reference Antenna           See Figure A.6.a-3         See Figure A.6.a-3      Meets reference
Pattern                                                                      radiation pattern set
                                                                                    forth in
                                                                            Recommendation ITU-


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                                                                              R S.465-6.
Polarization                   RHCP                    RHCP                     RHCP
Minimum Elevation                5°                      5°                       5°
Angle
Maximum Pass Length          590 seconds             590 seconds             590 seconds
Maximum Passes Per              3 to 4                  3 to 4                  4 to 5
Day


          Figure A.6.a-3 TT&C 3.0 meter Earth Station Antenna Transmit Pattern




The maximum uplink EIRP for the TT&C command link will be 48 dBW for the Brewster earth
station and 45 dBW for the Mojave and Albuquerque earth stations. The data rate will be 256
kbps. Right-hand circular polarization will be used for the command signal. Table A.6.a-2
shows the link budget for the command. These link budgets are for an EIRP level of 45 dBW.
For the 48 dBW EIRP uplink from the Brewster earth station, the link will close with additional
margin.




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                            Table A.6.a-2: TT&C Command Link Budget
                                                          5 deg El     10 deg El     45 deg El     90 deg El
                      Parameter                           (Peak)       (Peak)        (Peak)        (Peak)     Unit
                      Frequency                                  2.082         2.082         2.082      2.082 GHz
                      Altitude                                     500           500           500        500 km
                      Elevation Angle                                5            10            45         90 deg
                      Slant Range                              2077.96      1695.09         683.09    500.00 km
                      Range Factor                              137.34        135.58        127.68    124.97 dB
                      Aperture Factor                            27.82         27.82         27.82      27.82 dB
                      Path Loss                                -165.16      -163.40       -155.50 -152.79 dB
                      Atmospheric Loss                           -0.45         -0.23         -0.06      -0.04 dB
                      E/S Uplink EIRP                            45.00         45.00         45.00      45.00 dBW
                      Pol Loss                                       0             0             0          0 dB
                                                                                                                    2
                      Uplink Flux Density                       -92.34        -90.81        -82.74     -80.01 dBW/m
                      S/C ANT Gain                                 6.8           6.8           6.8        6.8 dBi
                      Signal Power at Antenna
                      Hardline Interface                        -113.81      -111.83      -103.76   -101.03 dBW
                      RX Input Loss                               -4.62        -4.62        -4.62     -4.62 dB
                      Signal Power at RX Input                   -88.44       -86.45       -78.38    -75.65 dBm
                      Min Acquire Threshold                     -103.00      -103.00      -103.00   -103.00 dBm
                      Margin without Interference                 14.56        16.55        24.62     27.35 dB
                      C/X Isolation at Antenna                     8.00         8.00         8.00     25.00 dB
                      Interf Gain @ Opposite Antenna              -6.00        -6.00        -6.00    -30.00 dBi
                      Interf Pwr at Rx Input, Total RSS         -101.11       -99.12       -91.05   -111.84 dBm
                      Signal Power at Rcvr Input,
                      Interference Degraded                      -88.68       -86.69       -78.63    -75.65 dBm
                      Margin to Threshold, WC Intf
                      Degraded                                    14.32        16.31        24.37     27.35 dB
                      Command Rcvr Noise Figure                     3.5          3.5          3.5       3.5 dB
                      Noise Density                             -170.48      -170.48      -170.48   -170.48 dBm/Hz
                      C/No, WC Intf Degraded                      81.80        83.79        91.85     94.82 dB-Hz
                                 -10
                      Eb/No @ 10 BER                                    13       13            13        13 dB
                      Implementation Loss                                2        2             2         2 dB
                      Bit rate                                         256      256           256       256 kbps
                      Bit rate BW                                    54.08    54.08         54.08     54.08 dB-Hz
                      Required S/No                                  69.08    69.08         69.08     69.08 dB-Hz
                      BER Margin                                     12.72    14.70         22.77     25.74 dB


The data rate for the telemetry link is 512 kbps with a maximum transmitter output power of 2.5
Watts. The peak antenna gain is 5.5 dBi. Right-hand circular polarization will be used for the
telemetry signal. The maximum EIRP after losses is 3.64 dBW. Table A.6.a-3 shows the link
budget for the telemetry link. These link budgets are for the Mojave and Albuquerque 3.0 meter
earth station antennas. Again, for the Brewster 7.6 meter antenna, the link will close with
additional margin due to the higher on-axis gain.




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                          Table A.6.a-3: TT&C Telemetry Link Budget
                                                            5 deg El       10 deg El      45 deg El     90 deg El
                         Parameter                          (Peak)         (Peak)         (Peak)        (Peak)    Unit
                         Frequency                               8.49625        8.49625        8.49625 8.49625 GHz
                         Altitude                                      500           500            500       500 km
                         Elevation Angle                                 5             10            45        90 deg
                         Slant Range                             2077.96        1695.09          683.09    500.00 km
                         Range Factor                              137.34         135.58         127.68    124.97 dB
                         Aperture Factor                             40.03         40.03          40.03     40.03 dB
                         Path Loss                                -177.38       -175.61        -167.72 -165.01 dB
                         Atmospheric Loss                             -0.6           -0.3         -0.07     -0.05 dB

                         Tx Power                                     2.5           2.5           2.5        2.5 W
                                                   in dBW            3.98          3.98          3.98       3.98 dBW
                         S/C Antenna Gain                             5.5           5.5           5.5        5.5 dBi
                         Tx Loss                                    -5.84         -5.84         -5.84      -5.84 dB
                         Transmit EIRP                               3.64          3.64          3.64       3.64 dBW
                           Transmit EIRP (W)                         2.31          2.31          2.31       2.31 W
                         Pol Loss                                       0             0             0          0 dB
                         Power at E/S                             -174.34       -172.27       -164.15    -161.42 dBW
                         C/X Isolation at S/C Antenna                5.00          5.00          5.00       8.00
                         Interf Gain @ Opposite Antenna             -6.00         -6.00         -6.00     -30.00 dBi
                         E/S G/T                                       25            25            25         25 dB/K
                         Downlink C/No                              79.26         81.33         89.45      92.18 dB-Hz
                         Downlink C/No, Intf Degraded               78.92         80.99         89.12      92.17 dB-Hz

                                          -6
                         Reqd Eb/No @ 10 BER                         10.5          10.5          10.5       10.5 dB
                         Coding Gain                                  5.5           5.5           5.5        5.5 dB
                         Implementation Loss                            2             2             2          2 dB
                         Bit rate                                     512           512           512        512 Kbps
                         Bit rate BW                                57.09         57.09         57.09      57.09 dB-Hz
                         Required S/No                              64.09         64.09         64.09      64.09 dB-Hz
                         Link Margin                                14.83         16.90         25.02      28.08 dB




For the E-band, there is one antenna onboard the spacecraft. This antenna is a parabolic, Axially
Displaced Ellipse (ADE) with a diameter of 50 cm. The maximum transmit gain for this antenna
is 49.7 dBiC and the maximum receive gain is 50.7 dBiC. Both right-hand circular and left-hand
circular polarizations will be used for the uplink and downlink transmissions. The satellite
transmit antenna gain patterns are shown in Figures A.6.a-4 and A.6.a-5. The satellite receive
antenna gain patterns are shown in Figures A.6.a-6 and A.6.a-7. The uplink transmissions are
received at center frequencies of 82 GHz and 85 GHz and the downlink transmissions are sent at
center frequencies of 72 GHz and 75 GHz. The occupied bandwidth for these carriers is 2.185
GHz. The satellite will normally only transmit and receive when the elevation angle from the
earth station to the satellite is greater than or equal to 30°; however, there are some specific
experiments in which the minimum elevation angle will be 10°.




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     Figure A.6.a-4 Athena E-Band Satellite Antenna Transmit Pattern (RHCP)




     Figure A.6.a-5 Athena E-Band Satellite Antenna Transmit Pattern (LHCP)




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     Figure A.6.a-6 Athena E-Band Satellite Antenna Receive Pattern (RHCP)




      Figure A.6.a-7 Athena E-Band Satellite Antenna Receive Pattern (LHCP)




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At the present time, there are three potential E-band earth station locations and two of these will
be selected to be used for the Athena satellite in the first half of 2018. Table A.6.a-4 gives the
technical parameters and pass information for the E-band earth stations.


                     Table A.6.a-4: Description of E-Band Earth Stations
                Location              Northridge,       Los Angeles     Santa Paula,
                                      California        County (Mt.      California
                                                          Wilson)
                Latitude (°N)          34.224241         34.224889       34.402443

                Longitude (°E)        -118.500349       -118.056639     -119.072900

                Antenna Size             1.2 m             2.4 m           2.4 m
                Maximum                 58.0 dBi          65.8 dBi        65.8 dBi
                Antenna Gain
                Reference              See Figure        See Figures     See Figures
                Antenna Pattern         A.6.a-8         A.6.1.a-9 and   A.6.1.a-9 and
                                                          A.6.a-10        A.6.a-10
                Nominal                   30                 30              30
                Minimum
                Elevation Angle
                Maximum Pass              228               228             228
                Length at Nominal
                                         (477)             (477)           (477)
                Minimum
                Elevation Angle
                (and at
                10°elevation)
                Passes Per Day          Up to 2           Up to 2         Up to 2




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 Figure A.6.a-8 Earth Station Pattern for 1.2m Ground Antenna at 76 GHz and 86 GHz




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 Figure A.6.a-9: LHCP Earth Station Antenna Pattern for 2.4 Meter Antenna at 83 GHz




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Figure A.6.a-10: LHCP Earth Station Principal Plane Pattern Cuts for 2.4 Meter Antenna
                         at 83 GHz (Peak Gain: 65.8 dBiC)




The baseline link budgets for the E-band uplink and downlink using a 2.4 meter earth station
antenna are given in Table A.6.a-5. The baseline link budgets for the E-band uplink and
downlink using a 1.2 meter backup earth station antenna are given in Table A.6.a-6. For the
uplink, a higher power option for the primary earth station’s 2.4 m antenna may be applied at the
midpoint of the mission. This higher power uplink would substitute (50W) traveling wavetube
amplifiers (TWT) for the existing solid-state earth station power amplifiers as a demonstration of
the viability of commercial E-band TWTs for space-based communication systems to drive
higher link data rates, which has not previously been publicly demonstrated. The higher power
2.4 m antenna will observe the same general operational principles as the initially deployed
antenna (e.g., number of passes, pass duration, elevation angles).




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        Table A.6.a-5: E-Band Link Budgets using 2.4 meter Earth Station Antenna

Link Parameter                           Downlink                 Uplink                HP Opt.
Carrier Frequency                  72.0GHz 75.0GHz         82.0GHz 85.0GHz        82.0GHz 85.0GHz
Wavelength                         0.0042m 0.0040m         0.0037m 0.0035m        0.0037m 0.0035m
RRC Roll-Off Factor                 α=0.37     α=0.37       α=0.37     α=0.37      α=0.37    α=0.37
Symbol Rate                      1.595GSps 1.595GSps     1.595GSps 1.595GSps     1.595GSps 1.595GSps
Occupied Bandwidth                2.185GHz 2.185GHz       2.185GHz 2.185GHz      2.185GHz 2.185GHz
Information Rate (/Ch/Pol)        2.65Gbps 2.65Gbps       2.65Gbps 2.65Gbps      7.94Gbps 7.94Gbps
TX Power Amplifier P1dB           30.0dBm 30.0dBm         33.0dBm 33.0dBm         47.0dBm 47.0dBm
Output Back-Off (OBO)                3.8dB      3.8dB        3.8dB      3.8dB       7.5dB     7.5dB
Post PA Losses                      1.55dB     1.55dB       1.55dB     1.55dB      1.55dB    1.55dB
Transmitted Power POut            24.6dBm 24.6dBm         27.6dBm 27.6dBm         37.9dBm 37.9dBm
Transmit Antenna Aperture           0.50m      0.50m        2.40m       2.40m       2.40m     2.40m
Half-power beamwidth                0.583°     0.560°       0.107°      0.103°     0.107°    0.103°
Transmit Aperture Efficiency          60%        60%          84%        84%         84%       84%
Transmit Antenna Gain              49.3dBi     49.7dBi      65.5dBi    65.8dBi     65.5dBi   65.8dBi
EIRP                              73.9dBm 74.3dBm         93.1dBm 93.4dBm        103.4dBm 103.8dBm
Transmit Antenna Pointing Loss      0.50dB     0.50dB       0.50dB     0.50dB      0.50dB    0.50dB
Radome Loss                         0.00dB     0.00dB       1.07dB     1.09dB      1.07dB    1.09dB
Link Distance Slant Range           909km      909km        909km      909km       909km     909km
Free Space Loss                    188.8dB 189.1dB         189.9dB 190.2dB        189.9dB 190.2dB
Propagation Loss                    8.60dB     8.60dB        5.5dB      5.5dB       5.5dB     5.5dB
Total Path Loss (Less Radomes)     197.4dB 197.7dB         195.4dB 195.7dB        195.4dB 195.7dB
Radome Loss                         1.25dB     1.17dB       0.00dB     0.00dB       0.0dB     0.0dB
Received Power at Antenna        -125.2dBm -125.1dBm     -103.8dBm -103.8dBm     -93.5dBm -93.5dBm
Receive Antenna Aperture             2.40m      2.40m       0.50m       0.50m       0.50m     0.50m
Receive Antenna Efficiency            84%        84%          60%        60%         60%       60%
Receive Antenna Gain                64.4dBi    64.7dBi      50.4dBi    50.7dBi     50.4dBi   50.7dBi
Receive Antenna Pointing Loss       0.50dB     0.50dB       0.50dB     0.50dB      0.50dB    0.50dB
Feed Loss                           0.10dB     0.10dB       0.10dB     0.10dB      0.10dB    0.10dB
Post-Feed Losses                    1.55dB     1.55dB       1.45dB     1.45dB      1.45dB    1.45dB
Received Power at LNA Input       -63.0dBm -62.5dBm       -55.5dBm -55.2dBm      -45.1dBm -44.8dBm
Receiver Noise Temperature           438.4K     438.4K       438.4K     438.4K      438.4K    438.4K
System Noise Temperature             697.0K     697.0K       668.0K     668.0K      668.0K    668.0K
Carrier to Noise (C/N)              15.2dB     15.6dB       22.9dB     23.2dB      33.2dB    33.5dB
Carrier to Interference (C/I)       40.0dB     40.0dB       40.0dB     40.0dB      40.0dB    40.0dB
Antenna Cross-Pol Isolation         35.0dB     35.0dB       35.0dB     35.0dB      35.0dB    35.0dB
C/(N+I)                             15.1dB     15.6dB       22.5dB     22.8dB      30.5dB    30.6dB
Link margin (dB)                     5.9dB      6.4dB       13.3dB     13.6dB       8.2dB     8.3dB
Total information rate (Gb/s)    10.59Gbps 10.59Gbps     10.59Gbps 10.59Gbps     31.77Gbps 31.77Gbps


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 Table A.6.a-6: E-Band Link Budgets for using 1.2 meter Backup Earth Station Antenna
Link Parameter                           Downlink                 Uplink                 HP Opt.
Carrier Frequency                  72.0GHz 75.0GHz         82.0GHz 85.0GHz         82.0GHz 85.0GHz
Wavelength                         0.0042m 0.0040m         0.0037m 0.0035m         0.0037m 0.0035m
RRC Roll-Off Factor                 α=0.37     α=0.37       α=0.37     α=0.37       α=0.37    α=0.37
Symbol Rate                      1.595GSps 1.595GSps     1.595GSps 1.595GSps     1.595GSps 1.595GSps
Occupied Bandwidth                2.185GHz 2.185GHz       2.185GHz 2.185GHz       2.185GHz 2.185GHz
Information Rate (/Ch/Pol)        2.65Gbps 2.65Gbps       2.65Gbps 2.65Gbps       7.94Gbps 7.94Gbps
TX Power Amplifier P1dB           30.0dBm 30.0dBm          33.0dBm 33.0dBm         47.0dBm 47.0dBm
Output Back-Off (OBO)                3.8dB      3.8dB        3.8dB      3.8dB        7.5dB     7.5dB
Post PA Losses                      1.55dB     1.55dB       1.55dB     1.55dB       1.55dB    1.55dB
Transmitted Power POut            24.6dBm 24.6dBm          27.6dBm 27.6dBm         37.9dBm 37.9dBm
Transmit Antenna Aperture           0.50m      0.50m        1.20m       1.20m        1.20m     1.20m
Half-power beamwidth                0.583°     0.560°       0.213°      0.206°      0.213°    0.206°
Transmit Aperture Efficiency          60%        60%          55%        55%          55%       55%
Transmit Antenna Gain               49.3dBi    49.7dBi      57.7dBi    58.0dBi      57.7dBi   58.0dBi
EIRP                              73.9dBm 74.3dBm          85.3dBm 85.6dBm         95.6dBm 95.9dBm
Transmit Antenna Pointing Loss      0.50dB     0.50dB       0.50dB     0.50dB       0.50dB    0.50dB
Radome Loss                         0.00dB     0.00dB       1.07dB     1.09dB       1.07dB    1.09dB
Link Distance Slant Range           909km      909km        909km      909km        909km     909km
Free Space Loss                    188.8dB 189.1dB         189.9dB 190.2dB         189.9dB 190.2dB
Propagation Loss                    8.60dB     8.60dB        5.5dB      5.5dB        5.5dB     5.5dB
Total Path Loss (Less Radomes)     197.4dB 197.7dB         195.4dB 195.7dB         195.4dB 195.7dB
Radome Loss                         1.25dB     1.17dB       0.00dB     0.00dB        0.0dB     0.0dB
Received Power at Antenna        -125.2dBm -125.1dBm     -111.7dBm -111.7dBm     -101.4dBm -101.4dBm
Receive Antenna Aperture             1.20m      1.20m       0.50m       0.50m        0.50m     0.50m
Receive Antenna Efficiency            55%        55%          60%        60%          60%       60%
Receive Antenna Gain               56.5dBi     56.9dBi      50.4dBi    50.7dBi      50.4dBi   50.7dBi
Receive Antenna Pointing Loss       0.50dB     0.50dB       0.50dB     0.50dB       0.50dB    0.50dB
Feed Loss                           0.10dB     0.10dB       0.10dB     0.10dB       0.10dB    0.10dB
Post-Feed Losses                    1.55dB     1.55dB       1.45dB     1.45dB       1.45dB    1.45dB
Received Power at LNA Input       -70.8dBm -70.4dBm       -63.3dBm -63.0dBm       -53.0dBm -52.7dBm
Receiver Noise Temperature           438.4K     438.4K       438.4K     438.4K       438.4K    438.4K
System Noise Temperature             697.0K     697.0K       668.0K     668.0K       668.0K    668.0K
Carrier to Noise (C/N)               7.3dB      7.8dB       15.0dB     15.3dB       25.4dB    25.7dB
Carrier to Interference (C/I)       40.0dB     40.0dB       40.0dB     40.0dB       40.0dB    40.0dB
Antenna Cross-Pol Isolation         35.0dB     35.0dB       35.0dB     35.0dB       35.0dB    35.0dB
C/(N+I)                              7.3dB      7.8dB       15.0dB     15.3dB       24.8dB    25.0dB
Link margin (dB)                    -1.9dB     -1.4dB        5.8dB      6.1dB        2.5dB     2.7dB
Total information rate (Gb/s)    10.59Gbps 10.59Gbps     10.59Gbps 10.59Gbps     31.77Gbps 31.77Gbps


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A.7    The Complete Program of Research and Experimentation Proposed, Including a
       Description of Equipment and Theory of Operation (Form 442 – Question 7a,
       §5.63(c)(1))

Space Systems/Loral (“SSL”) is the manufacturer of the Athena satellite. The satellite consists
of an SSL 100 bus customized to accommodate the Athena payload. Spacecraft mass is 150 kg
and volume approximately 0.33 cubic meters. The spacecraft bus is a three-axis stabilized bus
providing attitude control, power and communication channels to the payload. To support
payload activities, the bus will steer the spacecraft body towards a ground station, maintain
pointing throughout the payload operations, and provide the necessary power for the payload to
operate. During that entire time, the spacecraft will be in contact with the ground providing
telemetry and responding to commands. After payload activities are completed, the spacecraft
will return to a Sun pointing attitude that will allow its batteries to recharge in preparation for the
subsequent payload activity. Power is nominally only provided to the payload during
predetermined and commanded payload pass opportunities that align with contacts to the ground
stations noted in Table A.6.a-4. In addition, as the spacecraft passes in view of TT&C ground
stations noted in Table A.6.a-1 (outside of payload activities), it will download stored telemetry
to the ground as well as provide uplink opportunities for commands and uploads in preparation
of subsequent payload activities. Table A.7-1 and Table A.7-2 give the equipment
characteristics for the TT&C receiver and TT&C transmitter, respectively.




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                    Table A.7-1 TT+C Receiver Characteristics
               Parameter                              Value
           Signal Level Range               ≤ –100 dBm to ≥ –47 dBm
          Signal Sweep Range                       fR ±90 kHz
                                         ≤ –100 dBm at 1 kHz/s, 5 kHz/s
         Acquisition Threshold
                                     ≤ –90 dBm at 1 kHz/s, 5 kHz/s, 10 kHz/s
          RF Carrier Frequency                     2082 MHz
               Data Rate                           256 kbps
              Modulation                   BPSK modulation on carrier
      Command Threshold with BER
                                             ≤ –100 dBm at RF input
                of 10-6)
         Command Signal Level         ≤ –100 dBm to ≥ –47 dBm at RF input


                 Table A.7-2 TT+C Transmitter Characteristics




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 The E-band transceivers on the satellite and at the ground station are both of the direct-
 conversion I/Q modulation type (i.e., baseband signals are modulated/demodulated directly
 onto/from the E-band carriers via I/Q mixers). After modulation on the carriers, each transmit
 channel is routed through individual gain stages and power amplifiers before being combined
 and diplexed through the transceiver multiplexer. The receive paths are identical, but in reverse,
 and instead of power amplifiers, low noise amplification is utilized between the antenna port and
 the demodulator. The primary differences between the transceiver on the spacecraft and that in
 the ground station are (1) the transmit and receive bands are swapped and (2) there are higher-
 power amplifiers on the ground for the uplink signals. Key specification parameters at the air
 interfaces for these transceivers are provided in Table A.7-3.

                              Table A.7-3 E-band Transmitter Details

Key Performance Parameter       Specification              Comment
                                Downlink: 72 & 75GHz
Carrier Frequencies
                                Uplink: 82 & 85GHz
                                Downlink: +24.6 dBm
Maximum Transmitter RF          Uplink: +27.6 dBm
Output Power
                                Uplink HP Option: 37.9     As mentioned above and indicated in
                                dBm                        Tables A.6.a-5 and A.6.a-6, an optional
                                Downlink: 74.3 dBm         50W (+47 dBm) TWTA may be used late
                                                           in the mission for the uplink.
                                Uplink: 93.4 dBm
Maximum Transmit EIRP
                                Uplink HP Option: 103.8
                                dBm
                                ≤±4ppm/Temperature
Carrier Frequency Accuracy      ≤±1ppm/1st year,
                                ≤±5ppm/10 years
Carrier Phase Noise
1MHz Offset:                                               Applies to both transmit carrier and receive
                                ≤-95dBc/Hz
                                                           local oscillator signal (at E-band)
Integrated over 1-50MHz
                                ≤-38dBc
offset:
                                                           QPSK, 8APSK, 16QAM, 32QAM &
RF Modulation                   I/Q Modulation
                                                           64QAM
Pre-Mod RRC Roll-Off            0.37 nominal
Data Symbol Rate                1.595 GSps




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A.8    Cessation of Emissions (§25.207)


The satellite transmissions can be turned on and off by ground telecommand, thereby causing
cessation of emissions from the satellite, as required by §25.207 of the Commission's rules. For
the payload, the spacecraft simply cuts the power supply to the payload modules, inhibiting any
transmission of emissions; this is true for any time that the system is not executing a payload
contact to a ground station noted in A.6.a-4. For the TT&C chain, although the receiver part of
the transceiver is always expected to be on (when battery charge exceeds a certain state-of-
charge) in order to receive commands, the transmitter chain is commandable and can be turned
off to prevent any transmission of emissions.

The spacecraft power distribution unit has “end of mission” switches that inhibit charging of the
battery, causing a slow decay of the state of charge until ultimate passivation. The end of mission
switches are commandable (both ways), and the effect of closing the switches is slow enough to
allow reversal in case of inadvertent commanding.




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Document Created: 2019-03-13 09:30:12
Document Modified: 2019-03-13 09:30:12

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