Accurate Modelling of MHMIC Passive Elements Yields a Successful Design and Packaging of a 20 GHz to 5 GHZ MHMIC Low-Noise Downconverter

The MHMIC circuits described in this paper have been designed as part of a general technology development program, with some of them subsequently refined for specific applications. One example of this was a downconverter for portable transceivers operating at 20 GHz. The intended outdoor application imposed size restrictions and required that the units operate over a large temperature range. High reliability was also required. Furthermore, low noise and high gain with a very flat frequency response were dictated by overall system considerations. The focus of this paper is not the converter subsystem as such but rather the rationale behind the selection of a circuit technology suitable for applications like this and the corresponding design, modelling, packaging and, in particular, characterization and testing using techniques adaptable to automation.