PAPR optimization in MIMO-OFDM system for WiMAX

Future wireless communication is aiming at providing higher data rate services to meet the growing needs. The MIMO-OFDM technology aims at providing bandwidth efficient, higher capacity and higher data rate services to the customers. But, the major hindrance for OFDM is its high Peak to Average Power Ratio (PAPR). PAPR is the ratio of the high peak power to the average power of OFDM symbols. Various techniques have been deployed to reduce the PAPR such as Toning, Selective Level Mapping (SLM), Partial Transmit Sequence (PTS), Clipping and Filtering and Windowing. In this paper we present our optimized precoding and companding technique to optimize the PAPR and Bit Error Rate (BER) for WiMAX system. From the result, it is shown that the combination of precoding and Mu-law companding with QAM mapping technique provides better PAPR reduction. Simulations are carried out in MATLAB tool for different systems. From the results, it is observed that our proposed algorithm gives PAPR value of 1.7 dB which is 0.6 dB lesser than 2.3 dB.