Characteristics of an Inverted Shorted Annular-Ring-Reduced Surface-Wave Antenna

The electrical characteristics of an inverted shorted annular-ring-reduced surface-wave (RSW) antenna are presented in this letter. This microstrip antenna is designed for RSW excitation and lateral radiation and, hence, the characteristic patterns are relatively smooth in the forward region and demonstrate significantly reduced backscattered radiation, relative to a conventional microstrip patch. Results from a theoretical analysis of the antenna will be presented, along with confirming experimental results. These results include a radiation, input impedance, efficiency, bandwidth, directivity, and gain characterization of the antenna.