A microwave amplifier behavioral model capable of cascade simulation

In system-level design, microwave amplifier needs to be cascaded with other components. In this scenario, the input and output of amplifier model have cascade capability to sense the variation of source and load impedance, and thus can accurately predict the forward and reverse propagating waves. In this letter, the principle and an extraction flow for a simplified polynomial behavioral model are introduced, and the cascade capability of the model is verified by experimental source-pull and load-pull results. By simulations, a subcircuit with a low noise amplifier and a power amplifier, which are cascaded, is used to establish behavioral models using the proposed method. It shows that the proposed model results have good agreement with circuits using both continuous wave and modulated signal excitation. Finally, by measurements, the cascaded results of two amplifiers models are compared with the overall results. The results of output waves and magnitude/phase up to third harmonics are consistent with each other. These results verify that the proposed behavioral model has the capability of cascade simulation.

Automated summary

This paper introduces a simplified polynomial behavioral model which accurately predicts the forward and reverse propagating waves when a microwave amplifier is cascaded with other components. Experimental results verify the reliability and effectiveness of the model in cascade simulation.