Signal Detection In MIMO System

Multiple input multiple output (MIMO) transmit multiple data streams in parrallel subchannels in spatial, thus greatly increasing the system throughput without additional bandwidth and power requirements. While the signal detection in MIMO wireless communication systems is a key problem in MIMO system-related research that can never be bypassed.This thesis introduces the research of detection in MIMO wireless systems. First, it shows the model of MIMO, OFDM and MIMO-OFDM system. Second, it shows basic detection algorithms. And compare the performance and complexity through the simulation results. Then, shows two sorted QR decomposition detection algorithms based on Householder transform and Givens transform. The simulations show that although the detection orders obtained by the two algorithms are not optimal, they avoid matrix inversion operation, which reduce computation complexity and have little performance loss compared with IC based algorithms. Finally, an iterative receiver for coded G-STBC MIMO-OFDM system is presented, in which detection is performed by iterations between MIMO demodulator and a bank of MAP decoders based on the exchange of extrinsic information, it is SISO(soft input soft output ) detection. The simulation results demonstrate that the proposed iterative receiver has significant performance gain over the conventional non-iterative one and can obtain the performance approaching that of the iterative single-group receiveer at high SNR.