A design of ring-shaped dual-band/multi-band circularly polarized microstrip antenna based on slots mutual coupling

摘要

A new approach for designing a single-feed circular microstrip antenna with dual-band/multi-band circularly polarized (CP) radiation are demonstrated and studied experimentally. It is presented that by embedding pairs of asymmetrical ring-shaped arc slots to the boundary of both circular patch and the ground plane the impedance bandwidth of the antenna increases. This can be achieved by making use of both mutual coupling between the resonances of the ring-shaped arc slots and the fundamental resonances of the circular antenna. Also, by extending the ring-shaped arc slots out with narrow slots, the circular microstrip patch antenna can perform dual-band/multi-band CP radiation. Further details of the proposed CP microstrip antenna designs are described, and typical experimental results are presented and discussed.