OFDM系统中的一种自适应预失真器  

An adaptive predictor in OFDM system

作　　者：杨文考[1] 周尚波[1] 朱维乐[1] 

机构地区：[1]电子科技大学1603教研室,四川成都610054

出　　处：《电波科学学报》2003年第2期194-199,共6页Chinese Journal of Radio Science

摘　　要：对OFDM传输系统中大功率放大器非线性失真的数字自适应预失真技术进行了研究。利用有理双线性函数的非线性能较好地逼近大功率放大器的AM AM或AM PM非线性特性及其逆变换易于求解的特性 ,提出了一种新的数字自适应预失真方法 ,它是对估计器的输入幅度进行均匀量化 ,用一个估计器对大功率放大器的非线性特性进行估计 ,通过训练估计器的参数去调节预失真器的非线性参数 ,以达到预失真补偿的目的。与以前的方法比较 ,该方法用于正交频分复用 (OFDM )系统中具有收敛速度快、系统性能稳定。In this paper,a predication technology to compensate the high-power amplifier (HPA) nonlinearity in OFDM transmission systems is investigated. Using the nonlinear bilinear rational function to approximate HPA′s AM-AM or AM-PM nonlinear function and its inverse, a new digital adaptive predication scheme is presented. The input amplitudes are uniformly quantized, and an estimator is employed to evaluate the nonlinear characteristic curve of the HPA. To achieve the predication compensation, it adjust the nonlinear parameters of the predictor by training the parameters of the estimator. It is compared with the previous methods, the algorithm converges fast and robust and well effective compensation in the orthogonal frequency division multiplexing(OFDM) system.

关 键 词：0FDM 大功率放大器 非线性失真 自适应预失真器 正交频分复用 有理双线性函数 

分 类 号：TN919.8[电子电信—通信与信息系统]