Data Relay Satellite Antenna Subsystem Study. Volume 2

摘要

An antenna for a Data Relay Satellite linking four independent user satellites on low Earth orbits is proposed. Two users require accesses at Ka band, around 25 GHz, for high data rates, and the other two are at S Band, around 2 GHz, for medium and low data rates. An antenna diameter in the range of 260 cm is needed for each user. The preferred configuration is with separate S and Ka antennas. At S Band, it is recommended to use a single active array (dual access, Rx/Tx), and mass saving has to be achieved to make this solution even more attractive. At Ka band, two reflector antennas are foreseen: the feed system is fixed on the spacecraft and the scanning is obtained through a movement of the main reflector around the center of gravity, which reduces the impact of the attitude/orbit control system.