修正Volterra级数的功放行为模型

Modified Volterra Series Modeling for RF Power Amplifiers Based on Feedback Structure

从功率放大器的基本电路模型出发,建立了一种基于反馈结构的修正Volterra级数(MVS)的功率放大器的行为模型。在此基础上,依据功率放大器的非线性特性,对MVS模型进行了近似和简化,降低了模型的复杂度和参数提取时间。采用ADS仿真测量了一个10 W的WCDMA功率放大器的输入输出波形,用于模型提取和验证。计算结果表明,MVS模型能够很好地描述WCDMA功率放大器的非线性特性及记忆效应,与传统的记忆多项式模型(MP)相比较,MVS模型的NNSE低约3 dB,同时降低了模型的复杂度。

In this paper,a modified envelope-domain Volterra series model based on feedback structure is introduced.For the sake of reduction of model complexity and time cost during computation process,the MVS model is simplified by analyzing physical characteristics of power amplifiers and omitting those trivial components in the model.A 10 W WCDMA power amplifier is simulated in ADS for measuring input and output waveforms which are used in model extraction and verification for both MVS model and tradition MP model.Simulation results show that the MVS model can describe both dynamic nonlinearity and memory of power amplifier very well because its NMSE is 3 dB less than that of MP model,and at same time greatly decreases model complexity.