A [Formula Omitted]-Band CMOS FMCW Radar Transceiver for Snowpack Remote Sensing

• Published in: IEEE transactions on microwave theory and techniques Vol. 66; no. 5; p. 2480
• Main Authors: Kim, Yanghyo, Reck, Theodore J, Alonso-delPino, Maria, Painter, Thomas H, Marshall, Hans-Peter, Bair, Edward H, Dozier, Jeff, Chattopadhyay, Goutam, Kuo-Nan Liou, Mau-Chung, Frank Chang, Tang, Adrian
• Format: Journal Article
• Language: English
• Published: New York The Institute of Electrical and Electronics Engineers, Inc. (IEEE) 01-01-2018
• Subjects: Bandwidths; CMOS; Continuous radiation; Converters; Frequency synthesizers; Phase locked loops; Power consumption; Radar; Remote sensing; Snowpack; Superhigh frequencies; Transceivers; Unmanned aerial vehicles; Voltage controlled oscillators; Water management
• DOI: 10.1109/TMTT.2018.2799866
• EISSN: 1557-9670
• ISSN: 0018-9480

This paper presents a Ku-band (14-16 GHz) CMOS frequency-modulated continuous-wave (FMCW) radar transceiver developed to measure dry-snow depth for water management purposes and to aid in retrieval of snow water equivalent. An on-chip direct digital frequency synthesizer and digital-toanalog converter digitally generates a chirping waveform which then drives a ring oscillator-based Ku-Band phase-locked loop to provide the final Ku-band FMCW signal. Employing a ring oscillator as opposed to a tuned inductor-based oscillator (LC-VCO) allows the radar to achieve wide chirp bandwidth resulting in a higher axial resolution (7.5 cm), which is needed to accurately quantify the snowpack profile. The demonstrated radar chip is fabricated in a 65-nm CMOS process. The chip consumes 252.4 mW of power under 1.1-V supply, making its payload requirements suitable for observations from a small unmanned aerial vehicle.