Design of highly directive slot antenna using metamaterial structure under optimal condition

Abstract

In this article, a highly directive slot antenna design using a parallel incident magnetic metamaterial (MTM) structure has been presented. A split ring resonator (SRR) structure having mu near-zero and epsilon very large with low impedance behavior is employed to enhance the directivity of the antenna. In the proposed optimized design, four-MTM slabs with an array of 2 Â 2 SRR unit cell have been placed perpendicularly over the slot antenna to enhance the directivity. The thickness of utilized MTM slab in the vertical direction is under the optimal condition, which is highly desired to obtain better improvement in directivity. In spite of directivity enhancement of about 6 dB, antenna miniaturization of 11.4% is also obtained due to the loading effect of the MTM slab. The proposed directivity enhancement approach of the slot antenna is established by simulation and verified by measurements. It is perceived from both measured and simulated results that over the whole working band, a significant directivity enhancement is sustained along with reduced backward radiation compared to the unloaded slot.

Gap coupled symmetric split ring resonator based near zero index ENG metamaterial for gain improvement of monopole antenna

“…Frequency can be reconfigured using diode switches in the metamaterial. In another article, the directivity of the antenna has been increased by using near zero permeability metamaterial 20 . Moreover, metamaterial helps to reduce the overall dimension of the antenna by about 11.4%.…”