Fixed Service Satellite

Fixed Service Satellite (FSS) is the official classification (used chiefly in North America) for geostationary communications satellites used for broadcast feeds for television stations and radio stations and broadcast networks, as well as for telephony, telecommunications and data communications.

FSSs have also been used for Direct-To-Home (DTH) satellite television channels in North America since the late 1970s. This role has been mostly supplanted by direct broadcast satellite (DBS) television systems starting in 1994 when DirecTV launched the first DBS television system. However, FSSs in North America are also used to relay channels of cable TV networks from their originating studios to local cable headends and to the operations centers of DBS services (such as DirecTV and Dish Network) to be re-broadcast over their DBS systems.

FSSs were the first geosynchronous communications satellites launched in space (such as Intelsat 1 (Early Bird), Syncom 3, Anik 1, Westar 1, Satcom 1 and Ekran) and new ones are still being launched and utilized to this day.

FSSs operate in either the C band (from 3.7 to 4.2 GHz) or the FSS K_u bands (from 11.45 to 11.7 and 12.5 to 12.75 GHz in Europe, and 11.7 to 12.2 GHz in the United States). The higher frequency bands tend to have more spectrum and orbital slots available, but more expensive technology and higher rain margin.

FSSs operate at a lower power than DBSs, requiring a much larger dish than a DBS system, usually 3 to 8 feet (0.91 to 2.4 m) for K_u band, and 12 feet (3.7 m) or larger for C band (compared to 18 to 24 inches (460 to 610 mm) for DBS dishes). Also, unlike DBSs which use circular polarization on their transponders, FSS transponders use linear polarization.

Systems used to receive television channels and other feeds from FSSs are usually referred to as TVRO (Television Receive Only) systems, as well as being referred to as big-dish systems (due to the much larger dish size compared to systems for DBS reception), or, more pejoratively, "big ugly dish" (BUD) systems.

The Canadian Shaw Direct satellite TV service relies on FSS technology in the K_u band. Primestar in the USA used K_u transponders on an FSS as well for its delivery to subscribing households, until Primestar was acquired by DirecTV in 1999.