Impact Analysis of Metamaterial Superstrate Stack Loaded on the Top of the Microstrip Patch Antenna Structure for GSM Application

Abstract

This paper proposes a metamaterial stack loaded on the top of the rectangular microstrip patch antenna structure is presented. Metamaterial is developed  by composite materials  of  metals and dielectrics. In our proposed design, metamaterial stack is composited by copper metal and FR4 dielectric substrate. The proposed metamaterial stack is to form materials by using artificially designed and fabricated to achieve the unnatural electromagnetic properties. Therefore, it reveals negative permeability and permittivity characteristic properties that are retrieved from S- parameters by using Nicholson-Ross-Weir method at L-band (1-2 GHz). The L-band operation sets up the antenna to cover GSM band communication. The proposed metamaterial antenna structures reaches 4.13 dB gain enhancement compared to the antenna without metamaterial structure. The proposed metamaterial antenna resonants at 1.8 GHz for S-parameters of less than -10 dB. Antenna with metamaterial structure has been designed in CST Microwave Studio Suite software and fabricated by using basic Printed Circuit Board (PCB) manufacturing techniques on low priced FR4 substrate with ?_r = 4.4 and 0.16 cm thickness. The proposed fabricated antenna has been tested with the help of Keysight Programmable Network Analyzer ( E5071C ) to measure the return loss and VSWR. Also, the fabricated antenna has been tested under an Anechoic Chamber to measure the radiation patterns. From the simulation and the experimental results, an accurate radiation patterns have been achieved.

Keywords- Metamaterial, Negative Permeability and Permittivity; CST Microwave Studio Suite software; Network Analyzer and Anechoic Chamber