A W-band SiGe BiCMOS I/Q Receiver with Tunable Conversion Gain for Radar Applications

This paper presents an 89-102 GHz I/Q receiver (RX) containing an LO frequency multiplying chain (×4) manufactured in SiGe BiCMOS technology. The RX entails a two-stage low-noise amplifier (LNA) followed by a lumped version of Wilkinson power splitter to feed two mixers driven by LO signals shifted by 90 degrees. Quadrature LO signals are generated using a reduced-size branchline coupler. The mixing stage enables conversion gain (CG) tuning in 13.2-26.8 dB range at 94 GHz by means of pMOS transistors biased in triode region. The RX provides 13GHz 3-dB bandwidth with peak CG of 26.8 dB and NF of 11.7 dB consuming 80mA from 3.3V supply. The chip occupies 1.07mm ² silicon area.