基于EVM约束的预留子载波峰均比抑制

Tone Reservation Based on EVM Constraint for PAPR Reduction

传统预留子载波(Tone Reservation,TR)技术要求预留的子载波与数据子载波正交,占据的带宽受限,因而其降低峰值平均功率比(Peak-to-Average Power Ratio,PAPR)能力有限。提出了一种基于误差适量幅度(Error Vector Magnitude,EVM)约束的TR算法,将传统的预留子载波扩展至数据子载波生成峰值消除信号,从而大幅度降低峰值功率。基于系统误码率的考虑,在优化问题中加入数据子载波上会出现的最大EVM约束,采用凹凸过程(Concave-convex Procedure,CCCP)优化算法求解提出的优化问题。仿真结果表明,所提算法在发送端峰均比改善5.6 dB的同时,接收端解调性能仅损失1 dB。

The traditional Tone Reservation(TR)technology requires reserved subcarriers and data subcarriers to be orthogonal to each other,so the occupied bandwidth is limited,and its ability to reduce high peak-to-average power ratio(PAPR)is limited.This paper proposes a TR algorithm based on the error vector magnitude(EVM)constraint,which extends traditional reserved subcarriers to data subcarriers to generate peak cancellation signals,thereby greatly reducing peak power.And based on the consideration of systems’bit error rate(BER),the maximum EVM deviation constraint that will appear on data subcarriers is added to the optimization problem.The Concave-Convex Procedure(CCCP)algorithm is used to solve the proposed optimization problem.The conducted simulations and results show that when the proposed algorithm reduces PAPR by about 5.6 dB at the transmitter,the BER at the receiver only loses 1 dB.