Computer-aided noise analysis of MESFET and HEMT mixers

摘要

A numerical approach to the noise analysis of MESFET and HEMT mixers of arbitrary topology is discussed. A qualitative picture of the complex physical mechanisms responsible for the generation of the intermediate frequency (IF) noise is outlined, and the corresponding computational algorithms are presented. The derivation of a noisy nonlinear model for the microwave FET is addressed, and it is shown that a satisfactory solution to this problem can be obtained by combining a conventional time-domain model with standard noise information. The method has been implemented in a computer program designed to work in conjunction with an existing general-purpose harmonic-balance simulator. An application is described in detail to demonstrate the excellent performance of this software tool.