Attachment Technical Annex

This document pretains to SES-STA-20150326-00182 for Special Temporal Authority on a Satellite Earth Station filing.

IBFS_SESSTA2015032600182_1081303

                                           Attachment A

                                      TECHNICAL ANNEX

A.1    Scope and Purpose

       The purpose of this Attachment is to provide the Commission with the salient technical
characteristics of the Inmarsat-5 F3 satellite, as required by 47 C.F.R. §25.114 and other sections
of the FCC’s Part 25 rules, that cannot be captured by the Schedule S software.

A.2    General Description of Overall System Facilities, Operations and Services
       (§25.114(d)(1))

       The Inmarsat-5 F3 satellite will operate at the nominal 180° E.L. orbital location and will
provide fixed-satellite service (“FSS”) to earth stations in the Pacific Ocean region (see coverage
diagram in Figure A.2.1). The satellite will be operated at an offset location of 0.3 degrees from
180º E.L. to center the station-keeping box at 179.7º E.L. The satellite will operate in the 27.5-
30.0 GHz band (Earth-to-space) and 17.7-20.2 GHz band (space-to-Earth) portions of the Ka
band. The satellite network will employ two large gateway antennas and will provide service to
widely-deployed, small user antennas.

       The gateway antennas will be capable of communicating with the spacecraft throughout
the 27.5-30.0 GHz and 17.7-20.2 GHz bands. One gateway antenna will be located in Auckland,
New Zealand and the other one will be in Warkworth, New Zealand.

       TT&C operations will be provided by one of these gateway earth stations. On-station
TT&C transmissions will occur in the Ka band, and the spacecraft also will be capable of using
C-band frequencies for TT&C during transfer orbit and for emergency purposes. Because the
TT&C, feeder link frequencies and gateway antennas are not located in the United States, they
are not the subject of this application.

       This application seeks authority to serve the United States using only the 29.5-30.0 GHz
and 19.7-20.2 GHz portions of the Ka band. In this band, the user antennas will operate within
the “Global Payload Beams” or “GP Spot Beams” on the spacecraft. The Global Payload Beams
operate in the 29.5-30.0 GHz and 19.7-20.2 GHz bands and consist of 89 contiguous, fixed spot
beams. A representative depiction of the coverage of these beams is depicted in Figure A.2.1. A
sample Global Payload Beam coverage pattern is shown in Figure A.2.2.


                                       Figure A.2.1. Representative Global Payload Spot Beam Coverage




                                                                                                         FT
                           10.00




                               5.00
   Theta*sin(phi) in Degrees




                               0.00




                               -5.00




                  -10.00




                                       -10.00        -5.00             0.00               5.00   10.00
                                                             T heta*cos(phi) in Degrees




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seaibaq ut (yd)urs, ejoy




                           2.00




                   4.00 —


                                            1                                        1
                                  10.00   8.00          —6.00                .00   —2.00
                                                 Theta‘cos(phi) in Degrees


       The spacecraft will be capable of operating in the 29.0-29.5 GHz and 19.2-19.7 GHz
band segments for user terminals, but authority to operate user terminals in those band segments
is not sought in this application. The spacecraft also will be capable of using C-band frequencies
at 4199.0 MHz, 4199.5 MHz, 5926.2 MHz and 6422.5 MHz for TT&C during transfer orbit and
for emergency purposes. Certain of the beams described above will be switchable to also enable
communications in portions of the 20.2-21.2 GHz and 30.0-31.0 GHz bands, which are not
allocated for commercial service in the United States. Operations in these bands would occur
under the authority of Norway, pursuant to ITU filings submitted by the Norwegian
Administration. Authority to serve the United States using the frequency segments described in
this paragraph is not being requested in this application.

A.3    Predicted Space Station Antenna Gain Contours
       (§25.114(c)(vi))

       The Inmarsat-5 F3 satellite antenna gain contours for the receive and transmit beams, as
required by §25.114(d)(3), are given in GXT format in the GIMS container file included in this
application.

A.4    Frequency and Polarization Plan
       (§25.114(c)(4)(i))

       Details of the satellite’s Ka-band frequency plan is provided in the associated Schedule S
submission. The GP Spot Beams operate in RHCP on the uplink and LHCP on the downlink.
Consistent with Section 25.210(f), the GP Spot Beams employ an average six-fold frequency re-
use by spatial separation of co-frequency beams.

       In the GP Spot Beams, 72 channels are available in the forward link direction and 72 are
available in the return link direction, each with 40 MHz spacing and 32 MHz useful bandwidth.
These 72 channels in each direction are allocated among the 89 GP Spot Beams, with two
channels available in certain beams. The possible channel to beam allocation configurations in
the GP Spot Beams are as shown below.




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         Number of available channels Number of GP Spot Number of channels per GP
                                          Beams                  Spot Beam
         48 channels                      48 beams               1 channel (fixed)/beam
         24 channels                      12 beams               1 or 2 channels/beam
                                          29 beams               Up to 1 channel/beam
  Total 72 channels                       89 beams



A.5    Transponder Configuration

       The satellite has a total of 67 simultaneously active TWTAs, excluding TT&C functions.
This consists of 61 active TWTAs in the forward link direction (gateway-to-user) and 6 active
TWTAs in the return link direction (user-to-gateway).

       Note that in the associated Schedule S the term “transponder” refers to the useful
bandwidth of each channel (which is 32 MHz for the GP Spot Beams) and not to the number of
active TWTAs.

A.6    Services to be Provided
       (§25.114(d)(1))

       The Inmarsat-5 F3 satellite will provide a variety of two-way communications services to
small user terminals including broadband Internet access, multimedia, voice and other
applications.

       Representative link budgets, which include details of the transmission characteristics,
performance objectives and earth station characteristics, are provided in the associated Schedule
S submission.

A.7    TT&C Characteristics
       (§25.114(c)(4)(i))

       As noted above in Section A.2, on-station TT&C for Inmarsat-5 F3 will be provided by
gateway earth stations located in New Zealand, and authority for TT&C is not being sought in
this application.




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A.8    Satellite Transponder Frequency Responses
       (§25.114(c)(4)(v))

       The predicted receive and transmit channel filter response performance is given in Table
A.8.1 below. The receive response is measured from the satellite receive antenna up to the input
of the TWTA. The transmit response is measured from the input of the TWTA to the satellite
transmit antenna.

       Table A.8.1. GP Spot Beam Typical Receiver and Transmitter Filter Responses
               Frequency offset from      Gain relative to channel           Comments
                  channel center             center frequency

                                                    (dB)
                                          Receive       Transmit

                 CF +/- 11.2 MHz             1              1                 In-Band




                                                                     Value does not exceed these
                 CF +/- 12.8 MHz            1.3            1.3               p-p values
                 CF +/- 14.4 MHz             2              2
                    CF +/- 16 MHz            3              3
                 CF +/- 20.8 MHz             -1            -1               Out-of-Band
                                                                     Attenuation is not less than
                    CF +/- 24 MHz           -10            -7               these values
                 CF +/- 27.2 MHz            -25            -20



A.9    Cessation of Emissions
       (§25.207)

       All downlink transmissions can be turned on and off by ground telecommand, thereby
causing cessation of emissions from the satellite, as required.

A.10   Power Flux Density at the Earth’s Surface
       (§25.208(c))

       §25.208 does not contain any PFD limits that apply in the 19.7-20.2 GHz band for GSO
satellite networks, and it is noted also that Article 21 of the ITU Radio Regulations does not have
any PFD limits that apply in this band.




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A.11   Two Degree Compatibility
       (§25.138)

       Transmissions in the Inmarsat-5 F3 satellite network in the 29.5-30.0 GHz and 19.7-20.2
GHz bands will not exceed the uplink off-axis EIRP density and downlink PFD levels of
§25.138.

       §25.138 of the Commission’s rules defines the uplink and downlink parameters that
permit routine blanket licensing of Ka-band earth stations in certain frequency bands which
define the acceptable levels of adjacent satellite interference permitted in the Ka band by the
FCC, absent specific coordination agreements with neighboring satellites.
       For the 29.5-30.0 GHz and 19.7-20.2 GHz frequency bands, compliance with the
Commission’s two-degree spacing policy is ensured provided:

   •   The uplink off-axis EIRP density levels given in §25.138(a)(1) of the Commission’s rules
       are not exceeded; and
   •   The maximum downlink PFD levels given in §25.138(a)(6) of the Commission’s rules
       are not exceeded.
       The clear sky uplink off-axis EIRP density limits of §25.138(a)(1) are equivalent to a
maximum uplink input power density of -56.5 dBW/Hz for earth stations in compliance with off-
axis transmit gain masks in §25.209(a)(2) and (4).

       Table A.11.1 compares the uplink input power densities derived from the uplink link
budgets that are contained in the Schedule S with the clear sky limits of §25.138 (a)(1). It can be
seen that in all cases the clear sky uplink power limits are met.

Table A.11.1. Demonstration of Compliance with the Uplink Power limits of §25.138 (a)(1)
       Uplink Antenna Maximum Clear Sky Clear Sky Uplink     Margin (dB)
       Diameter       Uplink Input Power Input Power Density
                      Density (dBW/Hz) Limit of §25.138
                                         (a)(1) (dBW/Hz)

       13.2m                   -70.0 (*)              -56.5                 13.5
       Typical-60cm              -58.4                -56.5                  1.9
       Typical-100cm             -58.5                -56.5                  2.0
       Typical-150cm             -57.9                -56.5                  1.4
(*) Note: The Schedule S link budgets show a maximum uplink power density of -67 dBW/Hz
under faded condition from the 13.2 m antenna. Under clear sky condition the uplink power
density will not exceed -70 dBW/Hz.

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       In the band 19.7-20.2 GHz, the maximum downlink EIRP density that the Inmarsat-5 F3
satellite will transmit is 56.1 dBW in an occupied bandwidth of 32 MHz. This translates into 41
dBW in 1 MHz. The shortest distance from the satellite to the Earth is 35,786 km, corresponding
to a spreading loss of 162.06 dB. Therefore the maximum possible PFD at the Earth’s surface at
an elevation angle of 90° will not exceed -121.06 dBW/m2 in 1 MHz (i.e., 41 -162.06).

       In summary, all downlink transmissions from the Inmarsat-5 F3 satellite will comply
with the -118 dBW/m2/MHz limit set forth in §25.138(a)(6) of the Commission’s rules.

A.12   Orbital Debris Mitigation Plan
       (§25.114(d)(14))

       Inmarsat has incorporated the material objectives of §25.114(d)(14) of the Commission’s
Rules into the design of the satellite through the satellite’s Technical Specifications, Statement of
Work and Test Plans. The Statement of Work includes provisions to review orbital debris
mitigation, and compliance with §25.114(d)(14), as part of the preliminary design review
(“PDR”) and the critical design review (“CDR”) and to incorporate its requirements, as
appropriate, into its Test Plan, including a formal Failure Mode Verification Analysis (“FMVA”)
for orbital debris mitigation involving particularly the TT&C, propulsion and energy systems.

A.12.1 Spacecraft Hardware Design
       (§25.114(d)(14)(i))

       The satellite is based on the heritage Boeing 702 HP flight proven platform.

       Inmarsat will ensure that the satellite does not release any debris during its operation.
Furthermore, all separation and deployment mechanisms, and any other potential source of
debris will be retained by the spacecraft or launch vehicle.

       In conjunction with the satellite manufacturer, Inmarsat has assessed and limited the
probability of the satellite becoming a source of debris by collisions with small debris or
meteoroids of less than one centimeter in diameter that could cause loss of control and prevent
post-mission disposal. Inmarsat and the satellite manufacturer have taken steps to limit the
effects of such collisions through shielding, the placement of components, and the use of
redundant systems.




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       The Inmarsat-5 F3 satellite includes redundant TT&C and propulsion subsystems to
ensure successful end-of-life disposal. The spacecraft TT&C system, vital for orbit raising, will
be extremely rugged with regard to meteoroids smaller than 1 cm, by virtue of its redundancy,
shielding, separation of components and physical characteristics. The TT&C subsystem will
have no single points of failure. Near-omni-directional antenna coverage is provided through the
use of a combination of independent bicone and forward/aft pipe antennas. These antenna feeds
are extremely rugged and capable of providing adequate coverage even if struck, bent or
otherwise damaged by a small or medium sized particle. The command receivers and decoders
and telemetry encoders and transmitters will be located within a shielded area and will be totally
redundant and physically separated. Two shielded xenon tanks and a redundant pairs of thrusters
provide the energy for orbit-raising.

A.12.2 Accidental Explosion Assessment
       (§25.114(d)(14)(ii))

       The Inmarsat-5 F3 satellite will be a Boeing 702HP model spacecraft, which is designed
to minimize the potential for accidental explosions through propellant leakage and fuel and
oxidizer mixing or other means. Propellant tanks and thrusters are isolated using redundant
valves, and electrical power systems are shielded in accordance with standard industry practices.
During the mission, batteries and various critical areas of the propulsion subsystem will be
monitored to avoid conditions that could result in explosion. After the Boeing 702HP spacecraft
reaches its final disposal orbit, all on-board sources of stored energy will be removed by
depleting all propellant tanks, venting all (exception to helium as described below) pressurized
systems, discharging batteries, and turning off all active units.

       The Boeing 702HP spacecraft uses a bus that has a liquid propulsion system design
consisting of two helium tanks plus two pairs of fuel and oxidizer tanks and uses a xenon ion
propulsion system design consisting of two xenon tanks. Venting of the excess propellant in the
fuel, oxidizer and xenon tanks is performed as part of the end-of-life shutdown operations. The
helium tanks provide proper propellant tank pressurization for apogee engine firings during
transfer orbit. Consistent with Boeing’s practice with respect to a number of its spacecraft buses,
both helium tanks are isolated at the end of transfer orbit by firing pyro-valves. The spacecraft’s
helium system will be sealed when tanks are isolated, resulting in a final pressure of ~230 psi,
which is extremely low relative to the design burst pressure of 5250 psig (actual test performance

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at 6660 psig). Due to the low pressure at end-of-life in the helium tanks and their enclosure in
the spacecraft body, an explosive event is extremely unlikely (even in the event of a tank rupture,
e.g., a meteorite strike), minimizing the potential of any release of orbital debris. The xenon
tanks are vented by opening latch valves downstream of the tanks to allow cold flow through the
xenon ion thrusters.

A.12.3 Safe Flight Profiles
       (§25.114(d)(14)(iii))

        In considering current and planned satellites that may have a station-keeping volume that
overlaps the Inmarsat-5 F3 satellite, Inmarsat has reviewed the lists of FCC-authorized satellite
networks, as well as those that are currently under consideration by the FCC. In addition,
networks for which a request for coordination has been published by the ITU within ±0.15° of
179.7° E.L. have also been reviewed.

        Intelsat operates the C-/Ku-band Intelsat-18 satellite at 180º E.L. and with an east-west
station-keeping tolerance of ±0.05°. Thus, Inmarsat will locate the Inmarsat-5 F3 satellite at
179.7º E.L. in order to eliminate the possibility of any station-keeping volume overlap with the
Intelsat-18 satellite.

        There are no FCC licensed satellite networks nor are there any pending applications
before the Commission to operate a satellite within ±0.15° of 179.7° E.L. With respect to
published ITU filings, there are several networks filed within this sub-arc however other than
Intelsat-18, none are operational. Inmarsat can find no evidence that the other filed networks are
currently being progressed towards launch. Accordingly, Inmarsat concludes that physical
coordination of the Inmarsat-5 F3 satellite with any other party is not required at the present
time.

A.12.4 Post-Mission Disposal
       (§25.114(d)(14)(iv))

        At the end of the operational life of the Inmarsat-5 F3 satellite, Inmarsat will maneuver
the satellite to a disposal orbit with a minimum perigee of 300 km above the normal GSO
operational orbit. The post-mission disposal orbit altitude is based on the following calculation,
according to §25.283:

        Total Solar Pressure Area “A” = 93.1 m2

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       “M” = Dry Mass of Satellite = 3663 kg

       “CR” = Solar Pressure Radiation Coefficient = 1.29

       Therefore the Minimum Disposal Orbit Perigee Altitude is calculated as:

       = 36,021 km + 1000 x CR x A/M

       = 36,021 km + 1000 x 1.29 x 93.1/3663

       = 36,053.8 km

       = 267.8 km above GSO (35,786 km)

       To provide adequate margin, the disposal orbit will be increased to at least 300 km. This
will require approximately 1.4 kg of xenon propellant, taking account of all fuel measurement
uncertainties, which will be allocated and reserved in order to perform the final orbit raising
maneuver.




                          __________________________________




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                             ENGINEERING CERTIFICATION

       I hereby declare, under penalty of perjury, that the following statements are true and
correct to the best of my information and belief:
       (i)     I am the technically qualified person responsible for the engineering information
contained in the foregoing Application,
       (ii)    I am familiar with Part 25 of the Commission's Rules, and
       (iii)   I have either prepared or reviewed the engineering information contained in the
foregoing Application and found it to be complete and accurate.



                                             /s/


                                             Jonas Eneberg
                                             Vice President,
                                             International Spectrum Management
                                             Inmarsat

                                             Dated: ……………, 2015




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Document Created: 2015-03-26 11:32:49
Document Modified: 2015-03-26 11:32:49

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