Performance Analysis of Quasi-Orthogonal Space time turbo coded MIMO-OFDM System

Abstract: In wireless communication Multi Input Multi Output (MIMO) system increases the data rate and gives spacial diversity gain. MIMO in combination with Orthogonal Frequency Division Multiplexing (OFDM) becomes wideband transmission which enhances system capacity by resolving problem of Inter-Symbol Interference. Spacial diversity gain can be achieved by using space time block code without sacrificing bandwidth. In this paper, we proposed a Quasi-Orthogonal Space Time Block Code with Turbo Coding (QO-ST-TC) structure for MIMO-OFDM which gives full rate with coding gain. Also we have analysed QO-ST-TC for MIMO-OFDM over AWGN, Rayleigh and Rician channels and their effect on BER for high data rates have been presented. The simulation result shows QO-ST-TC for MIMO-OFDM system with 4X1 antenna configuration gives better performance in terms of BER.

Keywords: AWGN, Bit Error rate, Diversity, MIMO-OFDM, ML decoding, Q-OSTBC, Rician, Rayleigh, Simulink, Turbo coding, Wireless Metropolitan Area Network (WMAN).