A Study Of Cooperative Wireless Transmission Technologies Based OFDM

Cooperative communication provides an effective way to realize the Multiple InputMultiple Output(MIMO) technology by sharing the antennas on the multipleneighboring nodes in wireless communication system to construct virtual antenna arrayto achieve the similar diversity gain as the MIMO technology do.First, the fundamental principles of MIMO and OFDM are introduced briefly,followed by the coding and decoding of the Space Time Block Coding(STBC).Then, onthe basis of the basic cooperation strategies,the paper investigates the cooperativeschemes based OFDM and analyzes the different signal processing methods at the relaynodes in different channel conditions. The outage performance of the cooperationstrategies are compared and assessed. The theoretical derivation is correct verified bythe Matlab simulation results. Finally, in order to solve the problem of asynchronoustransmission, an Alamouti asynchronous cooperative transmission scheme based OFDMis given, the signal processing is described detailedly.Further, a new precodingcooperative transmission scheme based OFDM is presented in this paper, the newscheme can get the diversity gain without sacrificing the channel utilization comparedwith the original scheme. The new schemes can achieve higher diversity gain in thepremise of asynchronous transmission verified by the theoretical analysis and thesimulation results.