Neural network modeling of microwave FETs based on third-order distortion characterization
A new method for characterization of HEMT distortion parameters, which extracts the coefficents of a Taylor series expansion of I-ds(V-gs, V-ds), including all cross-terms, is developed from low-frequency harmonic measurements. The extracted parameters will be used either in a Volterra series model around a fixed bias point for 3(rd)-order characterization of small-signal I-ds nonlinearity, or in a large-signal model of I-ds characteristic, where its partial derivatives are locally characterized up to the 3(rd) order in the whole bias region, using a novel neural-network representation. The two models are verified by one-tone and two-tone intermodulation distortion (IMD) tests on a PHEMT device. (c) 2006 Wiley Periodicals, Inc.
neural networks volterra series intermodulation distortion microwave transistors nonlinear modeling