Design of an Aperture-Coupled Microstrip Array Antenna for Millimeter-wave Radar System

In this paper, we designed and interpreted the array antennas of the aperture-coupled microstrip operating in the millimeter-wave band for radar system. The microstrip array antenna can be designed with a transmission line circuit and a matching circuit in the same substrate. Therefore it is easy to combine with the active elements of the system. We add the slots to the patch to overcome it because general microstrip patch antennas have narrow band characteristics. we have designed the U-shaped slots in the patch. The substrate of patch for an aperture-coupled is used for general dielectric layer, and the substrate of transmission line for T-junction feeding is used FR4-epoxy. At this time, the analyzed center frequencies are 17 resonance mode from 24 GHz to 77 GHz at the 4☓4 array. As a result, this paper is proposed the possibility of prototyping by design of multi-mode array antenna in the millimeter-wave.