An automated millimeter-wave active load-pull measurement system based on six-port techniques

A millimeter-wave active load-pull measurement system for large-signal characterization of millimeter-wave transistors is presented. The characterization system uses two six-port junctions for simultaneous impedance and power flow measurements. Large-signal characterization of a GaAs FET operated in class A and class C at 28 GHz in terms of constant absorbed power contours, constant operating power gain contours and constant DC current contours in the load plane Z/sub L/ is presented. Effects of the unilaterality assumption on the operating power gain and output power are investigated for both class A and class C amplifier designs.>