System-on-Chip 36.8 GHz Radiometer for Space-Based Observation of Solar Flares: Feasibility Study in 0.25 μm SiGe BiCMOS Technology

This paper deals with a feasibility study for a System-on-Chip (SoC) mmwave radiometer devoted to space-based observation of solar flares and operating in the Ka-band. The radiometer has been designed in 250 nm SiGe BiCMOS process. The circuit integrates a three stages differential LNA with 37.2 dB gain and 4.8 dB noise figure at 36.8 GHz and a differential square-law detector based on HBTs, featuring a 96 mV/μW responsivity. The full radiometer achieves, potentially, a NETD of 0.1 K for 1 s integration time in Dicke mode. This work represents the first study of such an integrated instrument for Ka-band space-based observation of solar flares.