SIGSO satellite tracking characteristics of large-diameter parabolic antenna

SIGSO satellite is a special kind of geosynchronous orbit communications satellites. Its orbit height is the same as geostationary orbit, but its inclination varies periodically and annually, with variation in the range of 0 degrees to 15 degrees. When communication master station uses large-diameter antenna tracking SIGSO satellites, only a fraction of 1 degree of the antenna beam width is relatively small along with its inclination becomes bigger. Then which kind of tracking mode should be selected to keep precisely pointing to the SIGSO satellite becomes a very important issue. This paper takes Apstar-1 satellite as an example to analyze SIGSO satellites motion characteristics. Pros and cons of a 16-meter antenna with Truss-step tracking Apstar-1 satellite were studied and actual measurement was carried out in Beijing. Finally, mono-pulse tracking and turntable antenna mount is recommended which lays a good foundation for the system optimization design.