The impact of spatial correlation on performance of SFBC and VBLAST schemes on MIMO-OFDM-LTE

摘要

The 3G systems such as LTE as well as 4G systems will employ Multiple Input, Multiple Output (MIMO) transmission scheme based on OFDM (Orthogonal Frequency Division Multiple access) techniques. The LTE (Long Term Evolution) standard widely uses the MIMO-OFDM structure to improve downlink peak rate, cell coverage, as well as average cell throughput. In this paper, first, the performance of the SFBC (Space Frequency Block code) in MISO (Multiple Input Multiple Output) and MIMO channels are compared with SISO (Single Input Single Output) channel, and then performance of these two scheme, in frequency selective MIMO channel, in varying amount of correlation coefficient between uniform linear array antenna elements in transmitter and receiver, is checked. in this paper, simulation results show that the SFBC has a great impact on improving BER in low SNR whereas VBLAST (Vertical-Bell Laboratories Layered Space-Time) improve data rates in high SNR; also in both scheme, in environments with low correlation between antenna elements, with sufficient spacing between antenna elements, performance is improved.