New method for the analysis of dual-gate MESFET mixers

A method for the analysis of a microwave mixer based on a dual-gate MESFET is presented. The method extends a previously published analysis technique for a single-gate MESFET mixer by treating the circuit as a threeport network. The device is described by a complete mathematical model and the harmonic balance technique is utilised for the large-signal analysis stage. This results in a relatively fast program. The method is demonstrated by applying it to the simulation of a mixer based on a Raytheon transistor RDX832 for which device data was available. The mixer was constructed and its experimentally obtained performance results show good agreement between the simulated and the measured conversion gain values through a wide range of local-oscillator input power.