Description

Airborne radio telephone communication via a satellite is usually abbreviated to the term SATCOM.

Use of satellites for this purpose complements satellite-based navigation capability. Aircraft onboard equipment for SATCOM includes a satellite data unit, a high power amplifier and an antenna with a steerable beam. A typical aircraft SATCOM installation can support data link channels for ’packet data services’ as well as voice channels. SATCOM data link is currently used for only a small proportion of en route ATM communications in contrast to the much more extensive use as an alternative to VHF and HF for non-ATC purposes. The Asia-Pacific Region has been a particular focus for many of the early developments in the use of SATCOM for ATM data link. SATCOM functionality, which primarily depends upon geostationary satellites, is poor in polar regions, where HFDL (HF Data Link) provides equivalent service for some uses.