Design of low side lobe level milimeter-wave microstrip array antenna for automotive radar

A low profile array antenna with a low sidelobe was designed using Taylor array pattern synthesis and null filling concept is adopted using genetic algorithm. The antenna column is consists of 18 element antennas, gap coupled antenna is proposed in this paper to obtain low radiation coefficient and direct coupled antenna is used for high radiation coefficient. 45° polarization is added to reduce the interference. The antenna has 20.8dBi gain and sidelobe level of elevation direction is under -20dB and azimuth direction is under -25dB.