Transient analysis of nonlinear microwave circuits using small-signal scattering parameters

A transient analysis method for nonlinear microwave circuit analysis is described in this paper. S-parameter microwave circuit theory and measurement-based small-signal scattering parameters of nonlinear devices are used directly to construct the large signal response of the circuits. This consistent modeling and analysis approach retains all the frequency-dependence information of the measured small-signal parameters. The method is applied to predict the large signal performance of a discrete AlGaN/GaN high electron mobility transistor (HEMT), biased in the common source amplifier mode. Reasonable agreement between the simulated and measured results is obtained. This method does not have limitations on the number of input carrier frequencies or the total number of frequencies. It is expected to be a useful and efficient tool in waveform engineering applications.