A 220-325 GHz Subharmonic Receiver with 14.8 Db Peak Conversion Gain for FMCW Radar in SiGe BiCMOS Technology

In this paper an integrated J-band (220-325GHz) receiver is presented. It is implemented in a 130nmSiGe BiCMOS technology (ft/f max = 250/370GHz). The receiver consists of a subharmonic mixer (SHM) with additional LO and IF buffers and Marchand baluns for single-ended measurements. The SHM consists of two stacked switching quads with a subsequent cascode IF butter. The stacked switching quads are driven by an in-phase LO signal and do not require a space-consuming 90° coupler. The LO input is fed by the half RF frequency. Measurements within the RF input range of 300-325 GHz show a high peak conversion gain (CG) of 14. 80dB at 320 GHz and a DSB noise Figure of 20dB. The total DC power consumption is 175mW and the dimensions are (200 x 170)$\mu m^{2}$. To the best of the authors’ knowledge, this circuit has the highest broadband conversion gain reported in this frequency range and this SiGe technology.