A Hybrid Transform for Reduction of Peak to Average Power Ratio in OFDM System

Abstract

The performance of orthogonal frequency multiplexing (OFDM) communication systems is affected by the peak to average power ratio (PAPR). The research work uses a hybrid transform for reducing this PAPR value. In recent years, OFDM is more prevalent in the research field, particularly in wireless communication. OFDM system is found to have a high PAPR value. This high PAPR leads to nonlinear distortions that result in low power efficiency. Hence there is a need to minimize PAPR. Hadamard transform is a commonly used technique for the reduction of PAPR. However, greater efficiency can be carried out using a hybrid way to reducing the PAPR of the signals applying OFDM. Modified Discrete Cosine Transform (MDCT) combined with nonlinear companding technique, is suggested to minimize PAPR, described as a hybrid transform. It is shown that the hybrid transform achieves a better lessening of PAPR and minimized Bit Error Rate (BER) in the OFDM communication system when compared with the basic OFDM, Hadamard transforms, and Companding technique.