Low Power 75-110 GHz SiGe Dicke Radiometer Front-End

This paper presents a low-noise and low power calibrated radiometer (Dicke-radiometer), operating at 75-110 GHz and developed in 0.12 mu m SiGe BiCMOS technology. The chip consists of single-pole double-throw (SPDT) switch, low noise amplifier (LNA) and power detector (PD). The four-stage LNA provides 35.5 dB peak gain with 3 dB bandwidth of more than 35 GHz and noise figure of 5.5 dB. The SPDT shows measured insertion loss of 1.6 dB and an isolation of 24 dB at 94 GHz. The square-law power detector achieves responsivity of 25 kV/W and 1.4 pW/root Hz noise equivalent power (NEP). The integrated receiver results in peak responsivity of 59 MV/W, 4.8 fW/root Hz NEP and temperature resolution (NETD) of 0.1 K with 23.9 mW power consumption.