A 240-GHz circularly polarized FMCW radar based on a SiGe transceiver with a lens-coupled on-chip antenna

A 240-GHz monostatic circular polarized SiGe frequency-modulated continuous wave radar system based on a transceiver chip with a single on-chip antenna is presented. The radar transceiver front-end is implemented in a low-cost 0.13 µm SiGe HBT technology version with cut-off frequencies fT/fmax of 300/450 GHz. The transmit block comprises a wideband ×16 frequency multiplier chain, a three-stage PA, while the receive block consists of a low-noise amplifier, a fundamental quadrature down-conversion mixer, and a three-stage PA to drive the mixer. A differential branch-line coupler and a differential dual-polarized on-chip antenna are added on-chip to realize a fully integrated radar transceiver. All building blocks are implemented fully differential. The use of a single antenna in the circular polarized radar transceiver leads to compact size and high sensitivity. The measured peak-radiated power from the Si-lens equipped radar module is +11 dBm (equivalent isotropically radiated power) at 246 GHz and noise figure is 21 dB. The characterization bandwidth of the radar transceiver is 60 GHz around the center frequency of 240 GHz, and the simulated Tx-to-Rx leakage is below −20 dB from 230 to 260 GHz. After system calibration the resolution of the system to distinguish between two targets at different distance of 3.65 mm is achieved, which is only 21% above the theoretical limit.

[1]  A. Tessmann,et al.  A high performance 220-GHz broadband experimental radar , 2008, 2008 33rd International Conference on Infrared, Millimeter and Terahertz Waves.

[2]  Ken B. Cooper,et al.  Integrated 200–240-GHz FMCW Radar Transceiver Module , 2013, IEEE Transactions on Microwave Theory and Techniques.

[3]  Linus Maurer,et al.  77 GHz SiGe based bipolar transceivers for automotive radar applications — An industrial perspective , 2011, 2011 IEEE 9th International New Circuits and systems conference.

[4]  N. Llombart,et al.  Penetrating 3-D Imaging at 4- and 25-m Range Using a Submillimeter-Wave Radar , 2008, IEEE Transactions on Microwave Theory and Techniques.

[5]  Z. Tong,et al.  A 120-GHz FMCW radar frontend demonstrator based on a SiGe chipset , 2011, 2011 41st European Microwave Conference.

[6]  V.C. Chen,et al.  Detection and analysis of human motion by radar , 2008, 2008 IEEE Radar Conference.

[7]  Cunlin Zhang,et al.  Compact continuous-wave subterahertz system for inspection applications , 2005 .

[8]  B. Heinemann,et al.  Half-Terahertz SiGe BiCMOS technology , 2012, 2012 IEEE 12th Topical Meeting on Silicon Monolithic Integrated Circuits in RF Systems.

[9]  B. Floyd,et al.  60GHz transceiver circuits in SiGe bipolar technology , 2004, 2004 IEEE International Solid-State Circuits Conference (IEEE Cat. No.04CH37519).

[10]  Janusz Grzyb,et al.  A 0.32 THz FMCW radar system based on low-cost lens-integrated SiGe HBT front-ends , 2013, 2013 Proceedings of the ESSCIRC (ESSCIRC).

[11]  Songcheol Hong,et al.  24 GHz circularly polarized Doppler radar with a single antenna , 2005, 2005 European Microwave Conference.

[12]  Janusz Grzyb,et al.  A 240 GHz circular polarized FMCW radar based on a SiGe transceiver with a lens-integrated on-chip antenna , 2014, 2014 44th European Microwave Conference.

[13]  N. Pohl,et al.  A 240 GHz ultra-wideband FMCW radar system with on-chip antennas for high resolution radar imaging , 2013, 2013 IEEE MTT-S International Microwave Symposium Digest (MTT).

[14]  Changzhi Li,et al.  A Review on Recent Advances in Doppler Radar Sensors for Noncontact Healthcare Monitoring , 2013, IEEE Transactions on Microwave Theory and Techniques.

[15]  Ruey-Beei Wu,et al.  Antenna Design of 60-GHz Micro-Radar System-In-Package for Noncontact Vital Sign Detection , 2012, IEEE Antennas and Wireless Propagation Letters.