Theory and experiment of an antenna using a probe excited rectangular ring

This paper presents the theory and experiment of the antenna using a probe excited rectangular ring radiating bidirectional pattern. The antenna structure is simple and easy to fabricate. Since it requires only one connector, it is low cost and suitable for mass production. The radiation pattern appears to be the bidirectional beam without any side lobe. The ring width and height is selected based on the dominant mode propagation. The ring length is optimized to achieve the optimum radiation pattern. The polarization is vertical linear polarization at the boresight direction. The impedance matching can be achieved by adjusting the probe length. The optimum parameters are used as the guideline for the antenna design. The antenna prototypes were fabricated to measure the radiation pattern. The experimental results agreed reasonably with the theoretical calculations. It is confirmed that this antenna can be applied for the mobile communication with long and narrow path service area.