A simplified active load-pull behavioral model for power amplifiers

Abstract

To account for load impedance variation, the extraction methods of conventional nonlinear behavioral model require complex and expensive load-pull system. In this letter, a simplified behavioral model for power amplifier (PA) is demonstrated using nonlinear vector network analyzer (NVNA) only for data extraction. An incident signal at fundamental is added in the output of PA as a disturbance signal, and thus load reflection can be realized when its amplitude and phase are swept as active load-pull system does. To increase the robust of the model, a dynamic sweeping method of output incident signal is proposed which proved can cover most of the areas on the fundamental reflection coefficient chart. This method reduces the variables of the nonlinear behavioral model while dramatically simplifies the measurement architecture and reduces the cost of modeling.