MIMO-OFDM PAPR Reduction by Space-Frequency Permutation and Inversion

Multiple-input multiple-output (MIMO) orthogonal frequency division multiplexing (OFDM) has attracted much attention as a solution of high-quality service for next generation wireless communications. However, like OFDM, one of main problems of MIMO-OFDM is the high peak-to-average power ratio (PAPR). In this paper, a novel method to reduce the MIMO-OFDM PAPR is proposed. This method applies space and frequency two-dimensional subblock permutation and inversion to the multiple antenna OFDM signals based on STBC. Two suboptimal schemes, termed successive suboptimal SFPI (SS-SFPI) and random suboptimal SFPI (RS-SFPI) are presented to reduce the complexity of the proposed scheme. Simulation results show that SFPI improves PAPR reduction performance compared with existing PAPR scheme, and the suboptimal schemes can significantly reduce PAPR on all transmit branches at the same time with low complexity.