- News
7 June 2018
Imec demonstrates compact low-power 140GHz CMOS radar with on-chip antennas
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At the IEEE MTT-S International Microwave Symposium (IMS 2018) in Philadelphia, PA, USA, nanoelectronics research centre imec of Leuven, Belgium has unveiled what is said to be the first CMOS 140GHz radar-on-chip system with integrated antennas in standard 28nm technology.
The achievement is reckoned to be an important step in the development of radar-based sensors for smart intuitive applications such as building security, remote health monitoring of car drivers, breathing and heart rate of patients, and gesture recognition for man-machine interaction.
Radars are promising as sensors for contactless, non-intrusive interaction in Internet of Things (IoT) applications such as people detection & classification, vital signs monitoring and gesture interfacing. Broad adoption will only be possible if radars achieve a higher resolution, become much smaller, more power efficient to run, and cheaper to produce and to buy, so this is what imec’s research on 140GHz radar technology targets.
The low-power 140GHz radar solution comprises an imec proprietary two-antenna SISO (single-input single-output) radar transceiver chip and a frequency-modulated continuous-wave phase-locked loop (FMCW PLL), off-the shelf analog-to-digital converters (ADCs) and a field-programmable gate array (FPGA) and a Matlab chain. The transceiver features on-chip antennas achieving a gain close to 3dBi. The radar link budgets are supported due to a transmitter effective isotropic radiated power (EIRP) that exceeds 9dBm and a receiver noise figure below 6.4dB. The total power consumption for transmitter and receiver remains below 500mW, which can be further reduced by duty cycling. The FMCW PLL enables fast slopes up to 500MHz/µs over a 10GHz bandwidth around 140GHz with a slope linearity error below 0.5% and has a power consumption below 50mW. The FPGA contains real-time implementation of basic radar processing functions such as FFTs (fast Fourier transforms) and filters, and is complemented by a Matlab chain for detections, CFAR (constant false alarm rate), direction-of-arrival estimation and other advanced radar processing.
“With our prototype radar, we have demonstrated all critical specs for radar technology in 28nm standard CMOS technology,” says imec’s IoT program director Wim Van Thillo. “We are well advanced in incorporating multiple antenna paths in our most recent generation solution, which will enable a fine angular resolution of 1.5cm in a complete MIMO radar form factor of only a few square centimeters. We expect this prototype in the lab by the end of 2018, at which point our partners can start building their application demonstrators,” he adds. “First applications are expected to be person detection and classification for smart buildings, remote car driver vital signs monitoring (as cars evolve towards self-driving vehicles), and gesture recognition for intuitive man-machine interactions. Plenty more innovations will be enabled by this technology, once app developers start working with it.”
The imec 140GHz radar open innovation R&D collaborative program has been endorsed by Panasonic, and imec invites potential interested parties to join.
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