Mahdi Rostam Ali Farkhani - Telecommunication department, Power faculty, Adiban Higher Education Institute, Garmsar, Iran.
Mohammad Pour Ja’afar Jalali - Faculty member, Telecommunication department, Power faculty Power faculty,adiban university garmsar iran

According to the progress of science worldwide, the present article has dealt with a novel structure of ultra-wideband microstrip patch antenna using the theory of metamaterial circularly symmetric slot structure. Use has been made of the theory of the metamaterials’ circularity in designing the antenna. Negative refractive index, reduction in radar cross-section, omnidirectional pattern and good return losses, very small dimensions in respect compared to other metamaterials, receptivity in all of the ultra-wide bands and, of course, cost-effectiveness are amongst the properties of this constructed antenna. A prototype of this antenna was constructed and measured. The antenna’s substrate is made of FR-4 with 9.3×16×1.6 dimensions. The antenna’s radiative element is consisted of a rectangular radiative patch and its ground plane is also scalar so that the pattern could be made omnidirectional and a positive effect in s-parameter can be seen. In order to increase the bandwidth, the left and right corners of the feed line were slotted.

Ultra-wideband microstrip antenna, theory of metamaterials, extra small antenna