Software Research And Design On The Tracking System Of "Satcom On The Move" Satellite Communication Earth Station Based On Attitude Determination Instrument Using GPS

"Satcom on the move" (SOTM) system is an important part of mobile satellite communication system and it is currently playing an important role in the present society. In cases of natural calamities and emergencies, traditional communication equipment could be inoperative. Yet SOTM system can provide communication services quickly because of its unique advantages of flexibility and rapid response.This paper attempts to explore the vehicle SOTM. In practical use, antenna could change its pointing because of the movement of the vehicle. The sensors can obtain the information of changes and tendency of carrier’s movement. Then the system computes the pointing deviation of the antenna and makes the antenna move to the right place by controlling the motor. Hence SOTM can provide stable communication services. This research focuses on the software research and design of the tracking system, and explores five key technologies such as controlling a dc motor by using PWM technology, increasing the search efficiency by improving the search algorithm, improving the follow-up performance by using PID automatic control algorithm, etc. Meanwhile electronic compass has been replaced by attitude determination instrument by using GPS and the effect proves to be very positive.Currently, the key technology in tracking system has been solved and the system performance has accordingly been remarkably improved. The test results show that the design of the system is successful. And the next step is to test the system in real vehicle environment.