Abstract: This article presents and discusses a method to determine stability in nonlinear three-port circuits based on a generalized three-portlstability factor applied to linearized S parameters under large-signal pumping. A comparison with an extension of the conversion matrix-based, system pole-zero identification used to analyze circuit stability isalso presented. The relationship between the two techniques has been verified by means of an ideal two-port nonlinear circuit, and then, it has been applied in the design of a three-port millimeter-wave Monolithic Microwave Integrated Circuit (MMIC) up-converter. The circuit has been fabricated in a commercial GaAs process. On-wafer measurements showed an average conversion loss about 3.5 dB in a RF bandwidth between 40.4 and 41.5 GHz with local oscillator (LO) frequency fixed at 42.5 GHz. A RF/LO isolation better than 25 dB wasmeasured in the whole band, also showing outstanding intermodulation performance. With the proposed approach, the appearance of spurious oscillations was prevented.

Autoría

Descargar referencia