Polarization control of aperture coupled circular patch antennas
IEEE Conference on Antennas Measurements and Applications, Syracruse, USA
Tan, A.E., Riding, P.A., Eccleston, K.W., Platt, I.G., Woodhead, I.M.
In this paper, we propose an aperture coupled circular patch antenna that allows design flexibility of its polarization. The antenna comprises of two dielectric layers and three metal layers. The top layer contains a circular patch, the bottom layer contains the microstrip feed which is short-circuit terminated. The middle layer is the ground plane for both the patch and microstrip. A circular aperture in the ground plane couples the microstrip to the patch. The position of the microstrip termination is chosen to either maximize the electric field or, magnetic field, or obtain a combination of both at the aperture, to either excite one of two degenerate modes or both to obtain linear or circular polarizations respectively. Three circular patch antennas (two linear polarized and one circularly polarized) were designed, fabricated and measured. The antennas were designed for application in the 5.8 GHz ISM radio band, and had a dimension (including ground plane) of 50 mm × 50 mm.