Superdirective compact parasitic array of metamaterial-inspired electrically small antenna

Abstract

A metamaterial-inspired electrically small antenna design is presented. This antenna is based on a semi-loop near field parasitic element driven by an electrically small monopole antenna. The system has a dimension of λ0/24×λ0/24 and works in the UHF band, with a simulated efficiency of 14% and an average maximum gain of -5.6dB in the matched bandwidth of 18.4MHz. This antenna is then used in a two elements compact parasitic array, in order to achieve a higher directivity. The two elements of this array are identical, but only one of them is driven, the other one is used as a parasitic element. The design of the antenna, its simulated and measured radiation performance is reported, as well as those of the parasitic array.