COPLANAR MILLIMETER-WAVE ICS FOR W-BAND APPLICATIONS USING 0.15 MU-M PSEUDOMORPHIC MODFETS

A small signal S-parameter and noise model for the cascode MODFET has been validated up to 120 GHz, allowing predictable monolithic microwav e integrated circuit (MMIC) design up to W-band, The potential of copl anar waveguide technology to build compact, high performance system mo dules is demonstrated by means of passive and active MMIC components, The realized passive structures comprise a Wilkinson combiner/divider and a capacitively loaded ultra miniature branch line coupler, For bot h building blocks, very good agreement between the measured and modele d data is achieved up to 120 GHz, Based on the accurate design databas e, two versions of compact integrated amplifiers utilizing cascode dev ices for application in the 90-120 GHz frequency range were designed a nd fabricated, The MMIC's have 26.3 dB and 20 dB gain at 91 GHz and 11 0 GHz, respectively, A noise figure of 6.4 dB was measured at 110 GHz, The 90-100 GHz amplifier was integrated with an MMIC tunable oscillat or resulting in a W-band source delivering more than 6 dBm output powe r from 94 to 98 GHz.