F-OFDM系统的功率放大器非线性失真优化设计  

Nonlinear Distortion Optimization Design for RF Power Amplifier in Filtered-OFDM System

作　　者：卿敏杰 罗志年 QING Min-jie;LUO Zhi-nian(College of Computer Science and Electronics Engineering,Hunan University,Changsha 410082,China)

机构地区：[1]湖南大学信息科学与工程学院,湖南长沙410082

出　　处：《计算机仿真》2021年第8期299-304,共6页Computer Simulation

基　　金：国家自然科学基金项目(61371115);湖南省自然科学基金(2018JJ065)。

摘　　要：针对滤波正交频分复用技术(F-OFDM)中功率放大器的非线性失真问题,设计一种基于反馈项的数字预失真联合波峰因子降低技术的新结构对功率放大器的非线性特性进行补偿。波峰因子降低技术采用部分传输序列和压扩变换的融合算法,最大限度的降低输入信号的峰均比,使功放的工作区域无限接近于饱和区。为优化联合结构提出基于反馈项的短期输出信息的多项式模型应用至数字预失真间接学习结构中。仿真结果表明,新结构能够真实的捕捉到功放的非线性特性和记忆效应,有效地减少带外频谱扩展和非线性失真,缓解功率放大器的幅值和相位失真。The nonlinear distortion of the power amplifier(PA) is studied for Filtered Orthogonal Frequency Division Multiplexing(F-OFDM) systems,a new structure of digital predistortion(DPD) combined crest factor reduction(CFR) based on feedback term is designed to compensate the nonlinear characteristics of the PA.Joint partial transmission sequence(PTS) and companding transform(CT) are used as the CFR algorithm,which can lower input signal PAPR,and make the working region of PA infinitely close to the saturation region.In order to optimize the joint structure,a polynomial model based on the short period information of the feedback term is applied to the DPD indirect learning architecture(ILA).The simulations show that the proposed new model structure can truly capture the nonlinear characteristics and memory effects,effectively reduce out-of-band spectrum expansion and nonlinear distortion,and alleviate the amplitude and phase distortion.

关 键 词：滤波正交频分复用 数字预失真 波峰因子降低 功率放大器 

分 类 号：TP391.9[自动化与计算机技术—计算机应用技术]