Wiener功率放大器的分离预失真方法

Separation method of predistortion for Wiener PA

Hammerstein(以下简称H)系统能实现对Wiener功率放大器的预失真,文章从其结构特点出发,提出了分离预失真方法,将放大器中的记忆和非线性因素分离,并独立地得到各自的预失真模块,从而组成能对WienerPA进行线性化的H系统,克服了以往在对H系统各参数的辨识中,由于没有排除记忆和非线性因素的相互干扰而导致的算法较为复杂,收敛速度缓慢,收敛精度不高的问题。仿真表明,该方法在收敛速度和收敛精度上都有明显提高。

Wiener PA model can be perfectly predistorted by Hammerstein model. According to the structural characteristics of these two models, A separation predistortion method was proposed. The method first separated memory subsystem and nonlinear subsystem from Wiener PA, and then got their corresponding predistortion subsystems by identification algorithm. At last, it combined the two subsystems to a Hammerstein system and then linearized Wiener PA The method avoied interference between memory and nonlinear factors, This kind of interference can be found in the former methods which is not only complexity, but also leads to slow convergence speed and limited convergence precision. Simulation is made to signify that the method proposed is simple and can get more fast speed and more accurate convergence result.