Research On Detection Algorithm In MIMO System

Without increasing the bandwidth of wireless communication system,Multiple-Input Multiple-Output technology can multiply increase the signal channelcapacity and the frequency usage efficiency. Hereby it becomes a hot research zone inrecent years. However, the MIMO system adopts multiple antennas to transmit multiplesignals, which brings the difficulties to detect the signal in the receiver. Since thecapacity to detect signal affects the performance of the MIMO system, the detectionalgorithm has become a key research point for MIMO technology.Firstly, the model of MIMO system and space-time coding is briefly introduced inthis paper. Secondly, it introduces two kinds of MIMO transmission scheme which arebased on space-time block code and deduces the appropriate detection algorithmstheoretically. The feasibility of the algorithms is verified by simulation. Thirdly, a newcompletely interference cancellation detection algorithm is proposed on the basis ofstudying the traditional detection algorithms and the enhanced algorithms in V-BLASTsystem. This paper also studies the low complexity ML detection algorithm. And theperformances of above detection algorithms are compared by simulation. At last, treesearch algorithms based on QR decomposition are introduced, including spheredecoding of depth-first search and QRD-M algorithm of breadth-first search. Then anew QRD-M algorithm based on threshold setting is proposed and simulation showsthat the performance approximates QRD-M algorithm but with lower complexity.