Network analysis of nonlinear devices under multi-frequency excitation

This paper describes a measurement technique suitable for characterizing nonlinear microwave devices operating under multi-frequency excitation. A dual six-port network analyzer configured for simultaneous load-pull and source-pull measurement allows the characterization of nonlinear devices under multi-tone excitation, for use as mixers and broadband power amplifiers. The performance of a particular circuit can be optimize as a function of source and load impedances, at each input and output signal frequencies. Measurement results for the MESFET NE 76184, resistive mixer (2.9 to 7.1 GHz) show that a higher performance can be obtained by choosing independently the appropriate termination for input and output frequencies. The experimental results are also useful for the device modelling purposes