基于记忆有理函数的功率放大器行为模型

针对功率放大器的非线性特性及记忆效应,提出了一种基于记忆有理函数的功放行为模型。在传统记忆多项式模型和无记忆有理函数模型基础上,构建记忆有理函数模型,并利用共轭梯度法辨识模型系数,同时比较不同记忆深度和不同非线性阶数下的归一化均方误差,获取最佳记忆深度和非线性阶数。采用多载波的WCDMA信号和MRF6S21140H功放来验证模型的有效性,并与记忆多项式模型、无记忆有理函数模型进行了比较。结果表明,记忆有理函数模型在减少系数数目的同时具有更好的逼近精度。

Power amplifier behavioral modeling using memory rational function

Aiming at the nonlinear characteristics and memory effects of power amplifier, a memory rational function behavioral model, which based on the memory polynomial model and memoryless rational function model, is proposed. The model coefficients are identified by conjugate gradient method. The estimation of the best model nonlinearity order and the best memory depth is carried out by minimized the normalized mean squared error (MNSE). The model is validated using multi-carrier WCDMA signal and a MRF6S21140H power amplifier by measurement. The result indicates that the proposed model can achieve better model performance with less number of coefficients compared to the memory polynomial model and memoryless rational function model.