介绍了一种新颖的OFDM信号峰均比降低技术,不仅削去峰值信号,也削去谷值信号,从而最大程度上降低了信号的峰均比。矢量孔技术可以同时调整信号幅度和相位,使得信号矢量回避零点,信号谷值由此被削去。为了限制峰均比降低技术带来的带内和带外失真,该方法还进一步结合了闲置载波技术。仿真结果表明,经过该方法对QPSK调制的OFDM信号进行降低峰均比处理之后,信号峰均比从10.61dB降低到了7.03dB,EVM值保持为4.93%。该方法可以大幅度提高OFDM通信系统中功率放大器的效率和线性度。
A novel PAPR reduction,which clips not only peaks but also valleys of signal so that the peak-to-average power ratio(PAPR) can be reduced as much as possible,is proposed in this paper.Vector Hole Punching technique,which adjusts amplitude and phase of signal simultaneously to keep the signal vector away from the origin,is employed to clip valleys of signal.Furthermore,unused tone technique is also employed to depress out-of-band and in-band distortion caused by PAPR reduction.Simulation results show PAPR of a QPSK modulated OFDM signal is reduced from 10.61dB to 7.03dB with an EVM of 4.93% after the proposed PAPR reduction technique.This technique should vastly improve efficiency and linearity of power amplifier in OFDM communication system.