High-Precision D-Band FMCW-Radar Sensor Based on a Wideband SiGe-Transceiver MMIC

In this paper, a miniaturized D-band frequency-modulated continuous-wave (FMCW) radar sensor with 48-GHz bandwidth (32.8%, 122-170 GHz) and a high measurement rate of > 1 kHz for multi-target vibration measurements is presented. The sensor is based on a SiGe transceiver monolithic microwave integrated circuit manufactured via Infineon´s B7HF200 bipolar production technology with an fT of 170 GHz and fmax of 250 GHz. Gilbert cell, push-pull, and varactor-based doubler concepts on manufactured chips are compared, and the most promising signal source is embedded into a transceiver chip, which forms the main component of the presented radar sensor. The maximum output power of the system is ≈ -10 dBm and a phase noise of ≈ -80 dBc/Hz is achieved. Measurements are provided to demonstrate the sensor characteristics and show the promising results of FMCW radar in highest precision distance and multi-target vibration measurement applications. Due to the covered wide bandwidth, a range resolution of 5.88 mm is achieved ( -6-dB width, Tukey window). The sensor´s distance measurement repeatability is 290 nm (65 nm with 10 × averaging and 0.5-m target distance), and the distance measurement accuracy is m for a target in 65-cm distance moving 1 cm. Additionally, vibration measurement results and range-Doppler plots for advanced multi-target applications are presented.