Highly Miniaturized 120-GHz SIMO and MIMO Radar Sensor With On-Chip Folded Dipole Antennas for Range and Angular Measurements

This paper describes a highly miniaturized two-channel radar sensor with integrated on-chip folded dipole antennas that exhibit high antenna gain and radiation efficiency due to the use of the selective localized backside etching technique. The sensor can be utilized in single-input multiple-output radar system by combining the two transmit channels to increase the effective isotropic radiated power by 6 dB. This results in an improved standard deviation of range measurements by a factor of 2. The transceiver (TRX) is equipped with binary phase shift keying modulators as well as I/Q receivers and can be utilized in multiple-input multiple-output (MIMO) radar system using time and delta-sigma modulator-based frequency division multiplexing technique. The angular resolution is improved by a factor of 1.5 by the introduction of an additional virtual array element in the MIMO radar system. The TRX also includes a 30-GHz VCO that is complemented with a prescaler and frequency quadrupler to generate a 120-GHz carrier signal. Radar measurements using the digital-beamforming method with 10-GHz modulation bandwidth were performed to show the applicability of the proposed system.