60 GHz SiGe HBT downconversion mixer

This work presents an active downconverter targeted for integration in 60 GHz high speed data communication RF front-ends. The designed downconverter has been realized in 0.25 mum SiGe BiCMOS technology with f_t around 200 GHz. The downconverter consists of a single balanced mixer with an on-chip balun for differential to single ended conversion. High linearity and bandwidth are the main design goals rather than high gain. A clear-cut investigation of the applied bottom up design approach was presented with emphasis on modeling the critical on-chip signal path interconnects, matching and filtering components. The design and applied methodologies will be justified by comparing the measured and simulated performances. At 60 GHz an input 1-dB power compression of -5 dBm, 2.5 dB conversion gain and a gain variation around 2 dB from 50 to 70 GHz, are measured. Current consumption of the mixer core is 4.7 mA from a 3.3 V supply and the active chip area is 0.48 mm².