The Research Of Sphere Decoding Detection Algorithm In The Receiving End Of Spatial Multiplexing MIMO System

Spatial multiplexing MIMO system makes full use of wireless channel resources to send data streams while obey independent and identically distributed on different radio antenna, thereby obtaining reliable high-speed data transfer, while increasing the bandwidth efficiency of the system. Its doubles the channel capacity without increasing spectrum resources and antenna transmit power, and is one of a core technology in the field of a new generation of wireless communication.This paper focuses on the signal detection algorithm of the receiver of spatial multiplexing MIMO systems, aims to study and use of efficient and practical detection algorithm to achieve the goal of full using of the advantages of the system and reliable high-speed data transmission. Based on the analysis of the theory of linear detection algorithm, nonlinear detection algorithm, maximum likelihood detection algorithm and sphere decoding detection algorithm, first of all, the BER performance and complexity of maximum likelihood detection algorithm and sphere decoding detection algorithm is studied; Secondly, in view of the problems of that turnover radius of sphere decoding detection algorithm is too slow, emphasis on that sphere decoding detection algorithm is improved, the method of multiplying convergence factor in the radius replacement is used to increase the turnover rate of the radius and to make algorithm to find the optimal solution so fast on the process of sphere decoding detection; Finally, for the impact on reducing the error rate performance resulted in a large number of MIMO channel conditions, considering using the method of the optimization of lattice reduction to optimize the improved sphere decoding detection algorithm.Through a comparison of maximum likelihood detection algorithm, sphere decoding detection algorithm and its improved algorithm, found that the improved sphere decoding detection algorithm greatly reduce computational complexity and make convergence of the algorithm faster. Simulation results show that:Improved sphere decoding detection algorithm effectively reduce the complexity of the algorithm and improve system reliability.