W-Band cascode amplifier modules for passive imaging applications

W-band amplifier modules with high gain and large bandwidth have been developed for passive imaging applications. With three cascaded waveguide modules, an average small-signal gain of 60 dB and a +-3 dB bandwidth of 15 GHz was achieved centered around 94 GHz. The assembled three-stage amplifier monolithic microwave integrated circuits are realized in coplanar technology for compact size and low cost. Cascode devices, based on a 0.15 mu m AIGaAs/InGaAs/GaAs pseudomorphic high electron mobility transistor technology, allow for individual gain control of the stages by varying the second gate voltage.