Design of Circular Polarized Radial Line Slot Antennas

Abstract

A systematic design process for circular polarized radial line slot antennas is presented herein. In order to obtain circular polarization a spiral slot arrangement is needed. Slot coupling determination to obtain a desired aperture illumination is also important. The unit radiation element is composed of two slots that are designed to optimize the copolar to crosspolar ratio and the position and length of all the slots in the array can be determined with this method. Although the suggested method is suitable for obtaining any high or medium gain antenna, a direct broadcast satellite (DBS) reception antanna design is proposed as an application example.