Large-signal MESFET characterization using harmonic balance

A method is described that combines large-signal load tuning (i.e. load-pull) measurements with harmonic balance and optimization techniques to characterize GaAs MESFET devices. An important advantage of the method is that device model parameters are obtained at the frequencies at which the device will operate in circuits. Consequently, ambiguities regarding any frequency dependencies of the parameters are eliminated, thereby improving the accuracy of the device model and simulation. The method is best suited as a supplement to previously reported DC and small-signal parameter extraction methods, and is also applicable for the characterization of other power device types, including bipolar-junction transistors (BJTs).<>