I. Introduction
THE large-signal characterization of power transistors, makes traditional use of load–pull techniques and setups, in which constant wave (CW) test signals or modulated carriers drive the device-under-test (DUT). The main goals of such experiments are the search of optimal operating conditions of transistors to reach maximum output RF power, power-added efficiency or optimized tradeoffs between power efficiency, and linearity. They are also used for the validation and/or the refinement of nonlinear models of semiconductor (SC) devices used in computer-aided design (CAD) packages.