A Low-Complexity PAPR Reduction Scheme for SFBC MIMO-OFDM Systems

The multiple-input multiple-output (MIMO) orthogonal frequency division multiplexing (OFDM) system with space-frequency block coding (SFBC) is an attractive technique due to its robustness for time selective fading channels. However, the SFBC MIMO-OFDM system also inherits from OFDM systems the drawback of high peak-to-average power ratio (PAPR) of the transmitted signal. The selected mapping (SLM) method is a major scheme for PAPR reduction. Unfortunately, computational complexity of the traditional SLM scheme is relatively high since it requires a number of inverse fast Fourier transforms (IFFTs). In this letter, a low-complexity PAPR reduction scheme is proposed for SFBC MIMO-OFDM systems, needing only one IFFT. The proposed scheme exploits the time-domain signal properties of SFBC MIMO-OFDM systems to achieve a low-complexity architecture for candidate signal generation.