Forward link multiple access scheme for broadband and scalable mobile satellite communication system

The paper proposes and evaluates a forward link multiple access scheme for a next generation broadband and scalable mobile satellite communication system that offers transmission capacity of 1 Gbps and the maximum bit rate of 100 Mbps. Two major evaluation items are considered. (1) Capacity comparison is made among frequency reuse schemes: single frequency (SF); multiple frequency (MF); variable boundary multiple frequency (VMF). (2) Bit error rates are evaluated among four multiplexing schemes (FDM, OFDM, OCDM and TDM) in terms of required E_b/N₀ through nonlinear and frequency selective Rician fading channels. Evaluation results show that the proposed multiple access scheme, which combines VMF reuse with FDM or OFDM multiplexing, is the optimal solution.