An Investigation of Gain Enhancement of Microstrip Antenna by Using Inhomogeneous Triangular Metamaterial

Metamaterial have been shown to enhance specific performance parameters of low profile antennas. In this paper we investigate appreciably enhancement of the gain & radiation pattern of a low profile micro strip patch antenna by placing a metamaterial slab above it (as a superstrate) using CST MWS simulator. This paper proposes a metamaterial superstrate surface as a reflective surface for micro strip patch antenna (MPA). The MTM structure was a combination of the triangular SRR (TSRR) and the wire strip (WS) to obtain negative values of permittivity & permeability. The gain of the MPA with MRS is around 5 dB higher than that of conventional MPA on FR4 substrate. These improvements were due to negative refraction characteristics of LHM structure that converts into super-lens, when placed in front of the antenna. The small spacing between MRS and the patch surface was another merit in the present design, which was as low as λ/10 as it results in low profile antenna design, that will suits in modern wireless communication system.