Hard Sentenced Feedback Iteration And Testing Of The V-blast

Multiple Input Multiple Output (MIMO) technique is a great breakthrough in wireless communications, which can greatly increase the capacity and spectrum efficiency of a wireless system without occupying more bandwidth. This paper firstly introduces the basic concept and system model of MIMO, and then drives the formulas of channel capacity for the slow flat Rayleigh fading channels.We also explain current space time code schemes, that is, space time block code (STBC), space time trellis code (STTC) and differential space time block code (D-STBC).Their applications to future wireless communications are also introduced in this paper.Vertical Bell Laboratory Space Time (V-BLAST) can achieve a spectrum efficiency of more than 20 bps/Hz,which has attracted many research interests.In this paper, we firstly analyze the theory of V-BLAST and discuss the architecture of the transceiver, then study several detection algorithm for V-BLAST:maximum-likelihood(ML),zero-forcing and minimum mean squared error(MMSE),then discuss the interference cancel algorithm,lastly based on Golden algorithm,propose an improved V-BLAST dection scheme ,which greatly mproves the system performance.In this dissertation, we mainly focus on the performance analysis of horizontal coding (HC) and vertical coding(VC) in the iterative receiver with hard-decision feedback.In quasi-static Rayleigh fading channel, we firstly discuss the architecture of V-BLAST iterative receiver.Secondly, the performance of horizontal convolutional coding and vertical convolutional coding is evaluated through simulation.Unlike the conclusion drawn in some references that HC is better than VC,we show the iterative receiver structure greatly affect the performance of HC and VC.