Enhancement of the dipole antenna using a capcitively loaded loop (CLL) structure

Recently, metamaterials have become a research topic of considerable interest, because these artificially constructed materials allow for the realization of exotic electromagnetic properties not found in conventional materials. This paper introduces a novel antenna enhancing structure consisting of capacitively loaded loop (CLL) metamaterial elements placed radially around a standard dipole antenna at an electrically small distance. As a result of this novel arrangement, the dipole antenna is easily transformed into a directive mechanically scanned antenna with high realized gain. The desired directivity and gain can be tuned based on the number of radial CLL fins placed around the dipole. Interactions between the antenna and metamaterial elements result in significant enhancement of the maximum radiated field amplitude and front-to-back ratio. The structures presented are modeled using full-wave simulation and one is experimentally verified as a proof-of-concept.