A J- and D-Band Dual-Band Receiver for FMCW Radar and RadCom in a SiGe Technology

This paper presents a compact dual-band receiver for radar and RadCom applications, capable of simultaneously down-converting J -band $(220-325 \mathrm{GHz})$ and D-band ($110-170 \mathrm{GHz}$) signals with high conversion gain. Implemented in 130 nm SiGe BiCMOS technology, the receiver uses two stacked switching quads to subharmonically mix the J-band RF signal and down-convert D-band signals without additional circuit components. The in-phase LO signal driving both switching quads eliminates the need for 90° couplers, reducing the overall area to $(235 \times 180) \mu \mathrm{m}^{2}$. The receiver achieves peak conversion gains of 15 dB at 324 GHz and 19.7 dB at 162 GHz, with DSB noise figures below 21.9 dB and 15.9 dB, respectively, at a total power consumption of 129 mW. This low area and power consumption make large MIMO arrays with closely spaced dual-band antennas feasible for future RadCom applications.