Research On Coding And Detection Based On Multi-antenna System

In recent years,with the development of mobile communication,the current mobile communication system could no longer meet people's needs of obtaining such multimedia business as picture transmission,video chat,etc.which has higher requirements for communication quality.According to current users' requirements for more and more higher quality,people start to turn their study direction to next generation mobile communication the 5th generation wireless system(5G).To realize data transmission with large capacity and high speed under the complex communication environment,MIMO technology gains continuous development and improvement and it has also been written into related protocol standards as one of 5G's core technologies.This thesis mainly studies key technologies of space-time coding and detecting algorithm on the basis of MIMO technology.This thesis firstly introduces MIMO system model and overviews some common wireless channels' characteristics and diversity technique and then it discusses changes in MIMO system's channel capacity by theoretical derivation and system simulation;secondly,it studies and analyzes coding process of typical coding programs in MIMO system and provides applicable scenes for and corresponding advantages and disadvantages of various coding programs and it also studies the combined coding which integrates characteristics of both space-time block code and layered space-time code,improves its decoding algorithm and analyzes the improved result by simulation.At last,it studies how to remove the differential space-time code coding with channel correlation by using preweighting technique and applies multi-symbol detecting decoding in this new coding structure so as to give the system a better decoding performance.Later,it studies detecting algorithm in MIMO system including analysis of classic detecting algorithm's performance;it mainly studies Lattice Reduction(LR)technology and its LLL algorithm and optimizes the channel matrix with LR technology so as to give it a better orthogonality and it also applies this technology in detecting algorithm,focuses on improving the serial interference elimination algorithm and spherical decoding algorithm to give both algorithms better decoding performance after the improvement without bringing great complexity in the algorithm.This thesis uses simulation to verify the feasibility of the improved algorithm,advantages to be obtained compared with detecting algorithm and system performance that could be achieved.