High Accuracy Auto-Tracking Antenna System Using H-infinity Control for Earth Stations on Board Vessels
暂无分享,去创建一个
Broadband communication services are expected in all mobile environments. A satellite communication system is only way to provide access in many cases. Because the frequency bandwidth allocated to mobile satellite services (MSS) is insufficient, use of the frequency band for fixed satellite services (FSS) is considered. In this case, mobile antennas must have the same pointing accuracy as fixed earth stations. The constraints placed on the pointing error and other antenna attributes have been discussed in ITU-R. The provisional required pointing accuracy is 0.2 degrees. This level of accuracy is usually achieved only with expensive gyro systems and monopulse antennas. This paper describes a cost-effective antenna system that uses practical sensors and a step-track-like tracking technique. The key points described in this paper are the stable platform configuration, H-infinity digital controller, and dithering antenna pointing technique. Simulation results show that this antenna system meets the ITU-R requirements.