Phased arrays for satellites and the TDRSS antennas

The design and performance of satellite phased-array systems are examined by considering several specific antennas built for spacecraft use. Particular consideration is given to: (1) the JARED (Jammer Reduction Antenna System) antenna, and adaptive phased array which can be used to null jammer signals while providing coverage to specific user areas; (2) the algorithm used in the JARED antenna; and (3) a technique that can be used to detect and locate jammers. The antennas used by the Tracking and Data Relay Satellite System (TDRSS) are then described. A significant aspect of the TDRSS is the multiple access antenna which is a 30-element phased array, providing a single steered beam on transmit and the ability to receive data from 20 simultaneous users. Also included on the TDRSS is a mesh deployable reflector and a C-band and K-band communications system.