Research on adaptive transmission of time division duplex physical frame in mobile satellite system

An adaptive adjustment strategy in the transmission of physical frame is proposed for a satellite communication system based on time division duplexing. The proposed strategy adaptively adjusts both superframe length and uplink synchronization time according to the subregion determined by the positions of all active users. Meanwhile, a transition procedure for physical frame adjustment is also designed. Since the proposed strategy not only improves transmission efficiency as high as possible but also ensures data reliability, it establishes a foundation for the application of time division duplexing in satellite communication systems.