Patch antenna enhancement using a mushroom-like EBG structures

The mushroom-like EBG structure is used to suppress the surface waves excited by a patch antenna while improving its gain. The frequency band gap characteristics of the mushroom-like EBG was first determined with the aid of the dispersion diagram. A clear band gap was observed and the dimensions were tweaked to cover 2.4 GHz. It was found in order to effectively suppress the surface waves, a minimum of 3 columns of mushroom-like EBG is required to surround the patch antenna. Different configurations for the placement of the mushroom-like EBGs around the patch were also examined in order to minimize the overall size of the antenna. It is shown in the final design that the periodic structure can effectively increase the directivity and gain of the antenna.