PAPR reduction of OFDM signals using a nonlinear transform method

摘要

Orthogonal frequency division multiplexing (OFDM) is a multi-carrier system and more popular for high data rate communication in a wireless environment. However OFDM suffers from a major drawback of high peak to average power ratio (PAPR), which reduces the performance efficiency of the nonlinear power amplifiers used at the transmitter. Alternatively, to transmit the high PAPR without distortion, the power amplifier requires a wide dynamic range which increases the complexity and cost of the amplifier. Thus, we propose a new method to reduce the PAPR of the OFDM signals based on the μ-law with two inflection points, i.e., the compress and enhance parts of the μ-law operates on the OFDM signals that are greater than the large inflection point and lower than the small inflection point, respectively. Simulation results are presented to compare the PAPR and BER performance of the developed method with the μ-law and the linear companding transform (LCT).