Tongxin xuebao (Apr 2015)
Companding transform technique combined with iterative filtering for reducing PAPR of OFDM signals
Abstract
Considering the drawbacks of the traditional companding transforms,an efficient companding scheme combined with iterative filtering was proposed to reduce the peak-to-average power ratio (PAPR) of orthogonal frequency division multiplexing (OFDM) signals.By introducing a joint optimization approach for PAPR and bit error rate (BER) performances along with remaining an unchanged average output power level,the scheme could achieve significant reduction in PAPR as well as an improved BER simultaneously.Moreover,by adaptively adjusting the transform parameters in the iterative process,more design flexibility in companding form and lower out-of-band radiation could also be given to satisfy various system requirements.The proposed scheme had a simple functional form and less computational complexity.The theoretical results regarding the transform gain and impact of companding distortion were derived.Simulation results show that this scheme can substantially offer better overall performances in terms of PAPR reduction,BER performance and bandwidth efficiency.