77 and 94-GHz Downconversion Mixers in SiGe BiCMOS

Double-conversion superheterodyne downconverter blocks operating around 77 GHz and 94 GHz have been realized in 0.13-mum SiGe BiCMOS technology. Both use a single-balanced RF mixer to downconvert the signal to an 8.8 GHz IF, which is amplified and downconverted a second time to baseband. The 77-GHz circuit achieves an upper SSB NF of 12.8 dB at 77 GHz and <12 dB at 76 GHz, with 20 dB of conversion gain and an input-referred 1-dB compression point of -14.7 dBm. The 94-GHz circuit achieves an upper SSB NF of 17.2 dB at 94 GHz, with 15 dB of conversion gain and an input-referred 1-dB compression point of -10.7 dBm. Both circuits use a bias current of 3.2 mA in the RF mixer core, with total testsite power consumption of 120 mA from a 3-V supply.