Circular polarization microstrip antenna array with compact structure for anticollision radar

摘要

A multilayer slot-coupled microstrip antenna array is proposed for anticollision radar at 24GHz with circular polarization (CP) characteristic. The array is composed of 24 elements with 24-way microstrip line power divider network. The antenna can achieve CP by rotate the radiation patch a certain angle without polarizer. The VSWR coefficient of the array's ports is less than 1.8, and the side lobe level of array is below -26.5dB with axial ratio <;3dB in the mainlobe beamwidth. This antenna array has compact structure and small size, thus it will not impair the automobile outline.