Versatile Dual-Receiver 94-GHz FMCW Radar System With High Output Power and 26-GHz Tuning Range for High Distance Applications

Airborne applications demand exceptional overall radar system performance and eminently high output power for high range target detection. The frequency modulated continuous wave (FMCW) radar system presented in this article is capable of achieving this task due to its high output power at 94-GHz center frequency with over 26-GHz tuning range. Nevertheless, the radar still provides a small form factor and low power consumption of 4.25 W at 5 V single Universal Serial Bus (USB) supply. The key system component is a Silicon Germanium (SiGe) bipolar complementary metal-oxide-semiconductor (BiCMOS) monolithic microwave integrated circuit (MMIC) that contains a 94-GHz voltage-controlled oscillator (VCO), and a 27-GHz VCO for dual-loop phase-locked loop (PLL) stabilization, a power amplifier (PA), and two receive mixers. It generates frequency ramps between 83- and 109-GHz with a maximum output power of 19.7 dBm at its output after the bond wires on the printed circuit board (PCB) and 14.8-dBm output power at the radar's transmit (TX)-waveguide WR-10-flange. The sensor was also tested in a temperature range from -40 °C to +70 °C with menial deviation. Thus, the system offers high system dynamic range and far distance target detection range. Following a detailed system description, we finally present the FMCW range and Doppler measurements performed with the presented radar sensor as well as the application on unmanned aerial vehicles (UAVs) for flight altitude control and as airborne collision avoidance system (ACAS).