New generation WIMAX antenna based on metamaterial superstrate

Abstract

In this study, a microstrip patch antenna system based on metamaterial superstrate (PAMS) is proposed. Patch antennas suffer from low gain and directivity. A significant study is realized to circumvent this drawback by implementing a patch antenna based on metamaterial superstrate. The effective medium parameters of the unit cell are retrieved and planar three-layer metamaterial composed of unit cell arrays are used as a superstrate for gain and directivity enhancement of a microstrip patch antenna at 5.6 GHz. The gain and directivity efficiency of the proposed system is about 13.474 dB and 12.40 dB, respectively at 5.6 GHz. In this study, Simulation and measurement results are also presented. The PAMS consists of periodically arranged metamaterial array unit cells as a superstrate and patch antenna. The system is designed to operate from 5.2 GHz to 6 GHz with a return loss of -32.174 dB at first mode (5.6 GHz). Both simulation and measurement results of the PAMS show that this configuration is able to realize a broadside gain 72% of the maximum gain from the metamaterial superstrate. The effects of the compactness of the arrays are also investigated. It is observed that return loss is directly proportional with the compactness of the superstrate. The maximum return loss (-32.174 dB) is obtained with seven arrays of metamaterial.