基于功放效率的OFDM信号幅度的最佳分布——峰均比抑制  

Optimal OFDM Amplitude Distribution Method with Maximal HPA Efficiency——Peak to Average Power Ratio Reduction

作　　者：胡峰[1] 蔡超时[1] 刘昌银[1] 姚冬萍 宋洋 HU Feng;CAI Chao-shi;LIU Chang-yin;YAO Dong-ping;SONG Yang(Information Engineering School,Communication University of China,Beijing 100024,China;School of Electronic and Information Engineering,Beijing Jiaotong University,Beijing 100044,China)

机构地区：[1]中国传媒大学信息工程学院,北京100024 [2]北京交通大学电子信息工程学院,北京100044

出　　处：《电子学报》2018年第10期2450-2457,共8页Acta Electronica Sinica

摘　　要：星座图扩展(ACE)技术可以无损地降低OFDM信号的峰均比,本文的论述指出仅追求低峰均比对应的功放效率和效能并不是最好.笔者提出了OFDM信号的最佳互补累积分布函数(OCCDF)峰均比抑制方法,即考虑OFDM信号的幅度分布及出现概率,整体地评估其对放大器失真的影响,以OFDM信号放大器的效率为评估峰均比优劣的标准,在算法上以限定MER条件下得到尽可能低的功放输入功率回退(IBO)为迭代收敛目标,预见了应该存在最高功放效率意义匹配的所谓OFDM信号的最佳幅度分布.实验证实:相比原始OFDM系统,在放大基于OCCDF准则优化后的OFDM信号时,放大器获得了3. 15dB的IBO性能改善,对比同等条件下单载波系统仅差0. 05dB.For PAPR reduction in OFDM systems,active constellation extension(ACE)technique is attractive for practical implementation without any loss of data rate and quality.However,we observe it cannot achieve the maximal high power amplifiers(HPA)energy efficiency when the target is minimum PAPR.In this work,optimal complementary cumulative distribution function(OCCDF)evaluation metric is derived to integrally predict HPA quantitative distortions of each signal level and its probability distribution.To this distributing purpose,an iterative ACE algorithm is proposed to achieve the minimal input power back off(IBO)with maximal HPA efficiency suited OFDM signals for a modulation error ratio(MER)limited.It finally gives the performance results:The OFDM system with OCCDF PAPR reduction is shown to offer a 3.15dB IBO improvement than the system without PAPR reduction,which is 0.05 dB slightly inferior to the single carrier system.

关 键 词：最佳互补累积分布函数 峰均比抑制 最高功放效率 星座图扩展 

分 类 号：TN919.72[电子电信—通信与信息系统]