A design method of circularly polarized rectangular microstrip antenna by one‐point feed

Abstract

Abstract This paper describes a method for designing backfeed‐type one‐point fed circularly polarized antennas. These antennas are fed at one point from the back side of the substrate and have degeneracy‐resolving segments. Characteristics of the rectangular microstrip antennas with degeneracy‐resolving segments are obtained by means of a variational method. The equivalent circuit at and near the resonance with perturbations is obtained and the condition for circularly polarized antennas is found from both theoretical and experimental viewpoints. Configurations and radiation characteristics of these antennas are discussed and it is shown that these antennas can be used as array elements.