Role of FET size in the optimization of MMIC nonlinear performance

One of the main advantages of MMIC technology is the possibility of making a full use of scaling properties to improve performance. The majority of approaches which apply device-scaling only attend to linear criteria, without considering the improvement that could be achieved in nonlinear performance, like intermodulation distortion. In this paper, nonlinear design criteria are proposed to help in the selection of HEMT gate-width in MMICs, which are applied to several circuits, including a differential amplifier, a doubly balanced mixer and a single FET resistive mixer.