Design of multi-band rectangular patch antennas using defected ground structure (DGS)

Small size, multi-band rectangular microstrip patch antennas using Defected Ground Structure (DGS) for Wireless Local Area Network (WLAN-5.8 GHz), Worldwide interoperability for Microwave Access (WiMAX-5.8 GHz), Airport Surveillance (2.7-2.9 GHz), and Direct Broadcast Satellite (DBS) Europe (10.7-12.75 GHz) are presented in this paper. A thorough study has been made into the different multiband applications of the antennas using various slots such as square slot, triangular slot etc. in the ground plane. The above mentioned DGS patterns are simple and easy to etch on a commercial microstrip patch antenna. These structures reduce the cross-polarized (XP) radiation field without affecting the dominant mode input impedance and co-polarized radiation patterns of a conventional antenna. This novel concept (DGS) has been examined using CST Microwave Studio software employing a rectangular patch as the radiator. The proposed antennas have shown good radiation characteristics at various operating bands, which make them suitable for multi-band operations.