A self companding transform to.reduce peak-to-average power ratio in OFDM based WLANs

A high peak-to-average power ratio (PAPR) makes the orthogonal frequency division multiplexing (OFDM) based wireless local area lans (WLANs) sensitive to non-linear distortion in the transmission. The companding transform approach is a very attractive technique to reduce PAPR, but large PAPR reduction leads to a high bit-error rate (BER) by the available companding transform techniques. In this paper, we propose and analyze a new envelop equalized processing (EEP), which makes the amplitude of the OFDM signal constant. Based on the proposed EEP, a novel self companding transform (SCT) is constructed to reduce the PAPR of the orthogonal frequency division multiplexing signal. Simulation results show that the proposed SCT technique has a low bit error rate while achieving a significant reduction of PAPR, and outperforms the well-known clipping filtering(CF) scheme and the improved mu-law companding(ICT) technique substantially.