RGA based approach for PAPR reduction in OFDM systems

This paper proposes a novel scheme based on Relaxed Greedy Algorithm (RGA) to reduce Peak to Average Power Ratio (PAPR) in Orthogonal Frequency Division Multiplexing (OFDM) systems. OFDM uses a number of independent sub carriers of different frequencies for modulation. The resultant signals have very large PAPR which can significantly impact the power power efficiency and performance of a High Power Amplifier (HPA). We propose performing simple transformations on Sub Optimum Partial Transmit Sequence (SOPTS) combined with RGA. PAPR reduction of upto 5dB can be obtained and further side information need not be transmitted to the receiver. To further evaluate the PAPR reductions we compare the proposed scheme with the Sub optimum Partial Transmit Sequence (SOPTS) scheme based on Orthogonal Greedy algorithm (OGA). The results show that the proposed scheme offer better PAPR reduction than the OGA based SOPTS.