A Design Procedure for a Circular Polarized, Nearly Square Patch Antenna

The design of a compact, circular polarized (CP), nearly square patch antenna using an offset microstrip feed and operating at 2.45 GHz, is discussed. The effect of the offset on the perturbation segment and the design of a simple matching network is also mentioned. The radiation along the edges of the patch of two modes is modeled by two parallel tuned circuits, which are connected to the feed point by two transformers. It is shown that by using a single microstrip feed, offset from the corner and along one edge of the nearly square patch, the area of the perturbation segment is increased.