Peak-to-average power ratio reduction techniques for MIMO-OFDM systems with STBC/SFBC

Multiple-input multiple-output (MIMO) orthogonal frequency division multiplexing (OFDM) systems is a very attractive technique with high spectrum utilization and robust immunity against multi-path interference. However, one of the main problems of MIMO-OFDM is the high peak-to-average power ratio (PAPR) in the transmit signals. In this paper, we propose novel structures with more degrees of freedom to reduce PAPR, based on space-time block code (STBC) and space-frequency block code (SFBC). From the simulation results, we can see that the proposed scheme has better PAPR reduction performance of approximately 1dB then other traditional method. The BER simulation results also show that the proposed combining scheme is suitable for all proposed STBC/SFBC patterns, and performs as well as Alamouti combining scheme.