A novel TDMA frame structure for geostationary mobile satellite systems

A novel TDMA frame structure is proposed for a regional geostationary (GEO) mobile satellite service (MSS) system. It supports multiple users' data rates (8 kb/s to 64 kb/s) with hand-held terminals and permits dynamic change in user data rate during the call. The traditional frame structures provide variable rate service by assigning several time slots to higher data rate users. This is very inefficient in GEO-MSS systems since guard time and other overhead bits must exist in each time slot. The basic idea of the proposed scheme is to defragment time slots frequently in a frame to minimize noninformation bits and hence provides higher capacity. The improvement in the frame capacity is reported along with the procedure for the frame defragmentation dynamics.