Low Side-lobe, RCS Reduction Microstrip Antenna Array for 24 GHz Vehicle Millimetre Wave Radar

During the vehicle millimeter-wave radar application, the envelope signal would be continuously reflected between the bumper and radar, which causes the misjudgment in the direction of arrival (DoA). Thereby it is essential to improve the resolution through scattering the reflected envelope signal. Assuming the bumper installed in front of the radar, then the key of resolution enhancement resides in the backward scattering, or to say, the monostatic radar cross-section (RCS) reduction. This paper presents a hollow substrate with square unit cells, which form an artificial magnetic conductor (AMC) combining with the grounded substrate. Notably based on the array, we shaped the empty part for RCS reduction, also for low side-lobe.