A unidirectional beam antenna using a probe excited rectangular ring near the reflector

This paper proposes a unidirectional beam antenna using a probe excited rectangular ring near the reflector. The antenna structure is simple. The radiation characteristics of the antenna for various spacings between the probe excited rectangular ring and the reflector are analyzed. These characteristics are also compared with the conventional single aperture near the reflector. It is found that the proposed structure yields better characteristics than the conventional structure. The numerical results of the radiation pattern, elevational beam peak, beamwidth, and maximum directivity are investigated. The result of the analysis is very useful for the design of antennas of high directivity with unidirectional beam.