Research results of the radio-frequency characteristics of microwave devices

In this paper the research results of the radio-frequency characteristics of microwave devices are presented. The calculations were conducted with the application of a nonlinear physical-based model of a GaAs field-effect transistor with a Schottky barrier (MESFET). The comparative characteristics for the simulation analysis were extracted from measured S-parameters (Materka model), and the nonlinear physical model based on the analysis of the parameters of the semiconductor structure and the geometrical dimensions of the electrodes of the transistor, is deduced. Linear (gain, input/output VSWR) and nonlinear (output power, intermodulation distortion) parameters of a power amplifier are surveyed. The good coincidence of calculated and measured parameters is shown.