A Matrix Based SLM Scheme For PAPR Reduction In Alamouti MIMO-OFDM Systems Without Side Information

In this paper, a matrix based novel phase offset SLM scheme is combined with STFBC for PAPR reduction in Alamouti MIMO-OFDM systems without side information. The Selected Mapping (SLM) technique is one of the important PAPR reduction techniques for OFDM. This technique however increases the computational and phase search complexity and PAPR reduction is performance largely dependent on the selection of random phase sequences. It is also required to transmit the selected phase sequence to recover the original data at the receiver end. The other complexity is that the phase sequences are generated randomly in SLM.  So, in this paper we propose the use of Circulant, Hadamard, and Riemann and Hilbert matrices to obtain phase sequences for the SLM technique. We can also combine this matrix approach with the DCT transform for better performance. This approach also avoids randomness in phase sequence selection, which makes it simpler to decode at the receiver. As an added benefit, the matrix can be generated at the receiver end to obtain the data signal and hence it is not required to transmit Side information (SI).