The Research And Implementation For The Space-time Coding And Channel Estimation Of Mimo Communication System

In MIMO (Multiple Input Multiple Output) communication system, spatial diversity and spatial multiplex gains can be obtained, and hence bandwidth efficiency and system capacity can be evidently improved without augmenting the system bandwidth or the power of the antenna. Currently MIMO technology has been employed in many applications.In this thesis, we focus on space-time coding, channel estimation and hardware implementation of MIMO systems.Firstly the signal model of MIMO systems is described. We analyze the impact of the channel relativity on channel capacity and shows that MIMO technology can enhance system capacity. However, system capacity will decrease with the relativity of channel coefficients.Secondly the performance of Alamouti code is analyzed in an IF experimental system. The technologies of channel estimation of flat Rayleigh fading are summarized. Based on the classical simulation methods of MIMO channel models, we propose a method to simulate the channel of an MIMO system with 2 transmitters and 1 receiver. The method can also be applied to simulate the channels of MIMO systems without or with spatial relativity.Thirdly, hardware tests of Alamouti encoding and channel estimation for classical channel model are implemented on an IF experimental platform with FPGA. And some simulation results are presented.Finally the real-time adjustment of channel coefficients and parameter control of some key models are completed on a debugging software platform with Dephi.