一种具有普适性的功放线性化预失真方案

为解决功率放大器的非线性问题,提高功放效率,提出了一种能够应用于多种类型功放的间接结构多项式数字基带预失真方案。采取间接预失真结构规避了功放的辨识过程,选择记忆多项式模型作为预失真器能够线性化多种类型的功放,同时采用改进的抑制牛顿算法减少了参数的迭代次数和运算量。以64QAM信号作为输入,对几种典型的功放模型进行数字预失真处理,通过MATLAB仿真分析预失真前后信号的功率谱变化以及ACPR值的改变,表明该方案能够取得比较理想的预失真效果,同时证明了此预失真方案具有一定的普适性。

Robust predistortion proposal for power amplifier linearization

To linearize power amplifiers and improve efficiency, this paper found a robust predistortion proposal that could be used to several types of PAs. Using the indirect predistortion structure, it does not need to consider the PA's identification. Taking the memory polynomial model as predistorter, it could linearize more than one certain PA. And the improved Newton's method has less computation of polynomial coefficients. Some simulations were proceeded using 64-QAM signals and studies were done on the changes of power spectral density (PSD for short) and adjacent channel ratio (ACPR for short) before and after predistortion. The results show that this proposal can get good performances, proving its robust as well.