ARINC received FCC authorization to operate up to one thousand technically identical transmit/receive aircraft space stations. The ARINC SKYLink System will provide travelers and flight crews on commercial airliners, corporate business jets and smaller aircraft operating in the continental United States and over U.S. territorial waters access to the Internet and private corporate networks. ARINC held an experimental license permitting commercial operation of fifteen SKYLink terminals until May 1, 2006. With this authorization for 1,000 terminals, ARINC will be able to provide competition to Boeing, which was previously granted authorization for a satellite-based broadband data service to aircraft.
The FCC Order and Authorization describes how the SKYLink system works. Aircraft stations use 14.0-14.5 GHz for uplink and 11.7-12.2 GHz for downlink. These bands are allocated domestically and internationally on a primary basis for very small aperture terminal (VSAT) fixed satellite service (FSS) operation. Aeronautical Mobile Satellite Service (AMSS) use of this spectrum is on a secondary basis.
The SKYLink System uses a steerable 11.5-inch (29 cm) parabolic dish mounted in a radome on the aircraft's tail stabilizer. It is continuously steered in three axes under the control of an open-loop algorithm to "optimize coupling with the target satellite." If the received signal is interrupted, indicating the antenna has lost lock on the satellite, the transmitter will shut down within 250 milliseconds. The transmitters can also be shut down from ground control stations. ARINC's SKYLink will use transponders on the SES Americom AMC-1 satellite and a hub earth station in California to complete the circuit. Forward links can support data-transmission rates up to 3.5 Mbps.
The FCC Order and Authorization includes this description of the airborne uplink part of the system::
"Forward link signals are encoded using a randomized rate 1/3 code, direct sequence spread spectrum, with an integer chip rate to fit within the available bandwidth, then applied to a pulse shaping Offset-Quadrature Phase Shift Keying modulator that formats the signal for transmission over a 36 MHz transponder. The return-link waveform is direct-sequence-spread, Gaussian Minimum Shift Keyed with Forward Error Correction encoding and interleaving. Individual AES terminals access the shared return link using a random-access-burst Code Reuse Multiple Access Aloha contention protocol. Multiple terminals can concurrently share a single SKYLink return-link frequency channel using burst transmissions with the same or different CDMA spreading codes."
More information, including the FCC's response to comments from Boeing and PanAmSat, can be found in the Order and Authorization (DA-05-1016).
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