A Novel Spatial-Multiplexing OFDM System with Transmit Diversity Based on SFBC

A novel spatial-multiplexing orthogonal frequency- division multiplexing (OFDM) transmission system with transmit diversity provided by space-frequency block code (SFBC) is proposed in this paper. The proposed scheme combines Alamouti scheme and Bell Labs layered space-time (BLAST) together, thus can achieve transmit diversity and spatial multiplexing gains altogether. Two-step iterative detection algorithm is also proposed for this system, in which MMSE detection is performed firstly and then SFBC decoding coupled with successive interference cancellation (SIC) is performed separately and iteratively for each layer. Simulation results show that the proposed system with iterative detection algorithm can achieve better tradeoff between transmission rate and bit error rate (BER) performance than existing multiple-input multiple-output (MIMO) OFDM systems.