开关功率放大器非线性校正技术研究

摘要

开关功率放大器非线性主要来自器件本身，自适应预失真是用来补偿器件非线性失真的一种有效技术。针对开关功率放大器的非线性特性，文章首先建立它的模型，并使用NMSE评价指标对模型进行评价。在使输出线性化和功率最大化下，使用Wiener模型估计器来构成间接预失真线性化系统，并且用高斯-牛顿迭代法对预失真模型的参数识别进行优化。最后，仿真和实验结果都表明非线性校正的方法能有效补偿开关功率放大器的非线性失真，提高开关功放性能。%Switching power amplifier is the main device generates nonlinear distortion, the adaptive predistortion tech-nique is an effective technique to compensate for the switching power amplifier nonlinear distortion.For non-linear characteristics of the switching power amplifier, power amplifier model is established at first in the text and then use NMSE evaluation model.On the establishment of switching power amplifier polynomial model, taking into account the linearization, and to maximize the power out put amplitude limit we use Wiener model estimator to constitute indirect predistortion linearization systems and Gauss-Newton iterative method for predistortion model parameter identification optimization.Finally, simulations and experiments validate that this nonlinear correction method can effectively com-pensate for switching power amplifier nonlinear distortion, and increase the switching amplifier performance.