Companding Technique Study for Reducing Peak-to-Average Power Ratio of OFDM Signals

This paper studied on companding technique for reducing peak-to-average power ratio (PAPR) of orthogonal frequency division multiplexing (OFDM) signals, and proposed a novel convergent companding function. The function makes the instantaneous power of OFDM signals form uniform distribution, realizing large signal compressing and small signal expanding without changing the average power of original signals. It can attain the PAPR less than 3dB through quantitatively tuning up parameters. Computer simulation shows that, comparing with the existent companding technique, this proposed one has not only lower computational complexity but also less spectrum distortion and lower bit error ratio under the same system condition. It´s really a practical and effective.