Characterization of harmonic distortion and memory effects for RF power amplifiers based on volterra algorithm

The characterization of RF power amplifiers can benefit from the classic Volterra series theory. As a frequency domain form of Volterra series, Volterra algorithm is constituted by Volterra basis and Volterra coefficients. In this paper, the process of extracting Volterra coefficients is proposed and simulated with the harmonic balance simulator. A five order Volterra algorithm has been used to predict time domain waveforms, and a better agreement has been achieved, contrasting with X-parameter model. As an application, two Volterra coefficients concerned with three-order intermodulations is useful for characterizing memory effects influenced by modulation bandwidth.