Size reduction of circular microstrip patch antenna through metamaterial / Suhaima Sulaiman

This paper recommends a circular microstrip patch antenna with DGS structure to be used in Wi-Fi application. The combination of a circular microstrip patch antenna with Defected Ground Structure (DGS) strictures at the ground plane is proposed to reduce the size of antenna. The antenna has been designed to improve the performance. The patch antenna is designed to resonate at 2.45 GHz. Metamaterial characteristics with negative permittivity and permeability of the proposed DGS structures have been verified using Nicolson-Ross-Weir (NRW) method. A complete simulation has been done using the Computer Simulation Technology Microwave Studio (CST-MWS) version 2011. The design was fabricated on Rogers RO3003 with permittivity, £r=3.00 and thickness, h=0.75mm. The measurements have been carried out to verify die performance of antenna by a Vector Network Analyzer (VNA). The results show that the size of antenna was reduced by 67% compared to conventional antenna. The best return loss obtained from the design was -45.77976 dB. The measurement results also prove that metamaterial antenna exhibits a better return loss of about -24.62 dB and -23.72 dB respectively. The bandwidths for metamaterial and conventional antenna are 20 MHz.