An Antenna Selection Algorithm Based On The Minimum Average BER Of Optimal VBLAST Subset

Compared with the single-input single-output (SISO) approach, the multiple-input multiple -output (MIMO) approach has the ability to achieve higher spectral efficiencies, and more and more attentions have been paid to MIMO technique. There are three types of MIMO implements—the space diversity technique, the space multiplexing technique and the hybrid technique of diversity and multiplexing. The space diversity technology is mainly used for reducing bit error rate (BER), the space multiplexing technology is mainly used for improving spectral efficiency, and the hybrid technique can compromise flexibly between BER and spectral efficiency performance. Considering the fact that there are differences among the MIMO sub-channel performances, the antenna combination processing can improve system performance further. The scheme of the most previous antenna selection is as following: a compact MIMO structure consists of part of antennas with better channel gain to reduce the system BER. This approach waste a part of the antenna resources but reduce the system capacity.In this paper, antenna selection scheme is that good sub-channel will be used by Vertical-Bell Laboratories-Layered-Space-Time (VBLAST) coding in order to play the advantage of space multiplexing to improve spectrum efficiency; the poor sub-channel will be used by STBC (Space Time Block Code) coding in order to play the advantages of space diversity to reduce system BER. The scheme features are maximizing use of the antenna of resources, and the MIMO system can achieve flexibility BER and spectrum efficiency trade-offs.This paper proposes a new antenna selection algorithm which based on the Minimum Average BER of Optimal VBLAST Subset. The approach use the analysis that the signal-to-noise ration is a weighted Chi-squared variable with the weight equal to the diagonal entry of the inverted transmit correlation matrix to develop the selection algorithms. The algorithm can maximize the use of antenna resources, and effectively reduce BER undertake channel capacity and obtain maximum system capacity on the condition of BER performance. The simulation results indicate that the proposed antenna selection algorithm improves the BER remarkably comparing with a VBLAST encoding MIMO system and increases effectively the capacity of selection VBLAST system.