改进算法的峰均比抑制联合预失真技术  

TECHNIQUE OF PAPR REDUCTION IN COMBINING PRE-DISTORTION WITH IMPROVED ALGORITHM

作　　者：李诗雨[1] 南敬昌[1] 汪赫瑜[1] 高明明[1] 

机构地区：[1]辽宁工程技术大学电子与信息工程学院,辽宁葫芦岛125105

出　　处：《计算机应用与软件》2013年第7期38-42,共5页Computer Applications and Software

基　　金：国家自然科学基金项目(60971048);国家科技重大专项(2010ZX03007-002-03)

摘　　要：研究正交频分复用OFDM(orthogonal frequency division multiplexing)传输系统中高功率放大器HPA(High power amplifier)的自适应预失真方法。为了减少HPA非线性对OFDM传输系统的影响,通过改进的限幅法与自适应预失真技术相结合,降低OFDM信号的峰均比值,扩大HPA的线性化范围,从而补偿功放的非线性特性。提出一种基于变步长的最小均方LMS(Least meansquare)算法,并将其应用到基于记忆多项式模型的数字预失真系统中。仿真结果表明:结合峰均比抑制技术与自适应预失真技术,其性能优于单独使用自适应预失真技术,而且新的算法能有效地改善放大器的非线性特性,带外频谱抑制达到28dB。The adaptive pre-distortion method for high-power amplifier （HPA） of the orthogonal frequency division multiplexing （OFDM） transmission system is studied. In order to reduce the influence of the non-linearity of HPA on OFDM transmission systems, by combining the improved clipping technology with adaptive pre-distortion technology, the PAPR of OFDM signals is reduced, and the linearity range of the HPA is expanded, therefore the non-linearity of the power amplifier is compensated. A variable step size-based Least mean square（LMS） al- gorithm is proposed and applied to the pre-distortion system which is based on memory polynomial model. Simulation results show that the per- formance of the technique combining PAPR reduction and pre-distortion together is superior to that of the adaptive pre-distortion technique be- ing applied only, and the new algorithm can effectively improve the nonlinear characteristics of the amplifier. It gets 28dB out-band suppres- stun gain

关 键 词：正交频分复用 数字预失真 峰均比 限幅 变步长LMS 

分 类 号：TP3[自动化与计算机技术—计算机科学与技术] TN91[电子电信—通信与信息系统]