Orbiter Ku-Band Integrated Radar and Communications Subsystem

The band subsystem for the NASA Space Shuttle Orbiter operates either as a radar system during rendezvous with other space vehicles or as a two-way communications system with the ground through the Tracking and Data Relay Satellite System (TDRSS). In its radar function the equipment searches for, acquires, tracks, and provides the spatial data needed to make a quick and efficient rendezvous. In its communications function it searches for, acquires, and tracks the TDRS to provide high quality two-way communications from the Orbiter to the ground station via the TDRS System. The communications and radar systems are integrated since components such as the transmitter, receiver, antenna, and servos can perform well in either role. This paper describes the equipment as used in both roles but focuses on communications capabilities.