Research On The Multiuser Detection Technology In Multibeam Satellite MIMO Communication System

For satellite communication systems with limited track resources and frequency resources,it is more suitable to come up with a technical scheme to meet the needs of high rate and high capacity communication in the future,and not to increase the bandwidth of the system and not consume too much satellite resources.Therefore,we envisage the application multiuser detection technology of the MIMO which usually applied on the ground to the multibeam satellite communication system.Firstly,based on the technology of the multibeam satellite system and the model of MIMO communication system,the multibeam satellite MIMO communication system is established.Aiming at the capacity limitation and multiple access interference in the system.In this model,according to the multi-user detection algorithm,the capacity of the forward link and the bit error rate of the reverse link are respectively carried out and being simulated.Secondly,The link model of multi beam satellite MIMO communication system is established.The capacity performance of the system is discussed when different multiuser detection techniques are used in the forward link of multibeam satellite MIMO(MUD2,time-sharing multiuser detection,space-time coding multi user detection).It is found that the users in the system will receive weak emission signals when they located at the edge of the beam.In order to ensure that users within the system can enjoy reasonable resource allocation.The problem is corrected by introducing intelligent particle swarm optimization algorithm.By modifying the shape of the edge beam,the attenuation of the signal will be compensated from the satellite to improve the user's receiving power and ensure the parallel system.Finally,In the reverse link,we aim at improving the decoding performance of the satellite terminal,reducing the bit error rate and reducing the complexity of the satellite terminal.Therefore,we study the optimized serial interference cancellation detection algorithm,including two kinds based on column norm and SINR sorting.Finally,by combining the idea of multi-order detection,a multi-order detection serial interference cancellation(MS_F_MMSE_GOSIC)algorithm based on the column norm is proposed.The feasibility of the scheme is verified by simulation.