DESIGN STUDIES OF MICROSTRIP PATCH ANTENNAS WITH SPECIFIC METAMATERIAL STRUCTURES FOR WLAN APPLICATIONS

Abstract

High performance, compact size and low cost are the basic requirements of modern microwave communication systems. Various technologies have been developed to fulfill these requirements such as Substrate Integrated Waveguides (SIWs), Photonic Band Gap Structures (PBG), Defected Ground Structures (DOS), Electromagnetic Metamaterial structures and so on. Among these, Metamaterials are relatively new and the potential application of these special class of materials have drawn much attention in last few decades. The potential applications of metamaterial structure to realize super lenses, the Invisibility Cloak, bending of microwave and electromagnetic shielding are the land marks. The application of Metamaterials in the field of microstrip patch antennas has gone a longer patch to enhance its performance like increasing directivity, gain, size reduction as well as in realization of beam scanning antennas. In this dissertation, basic theory of metamaterial structures has been studied. A literature survey has been done to explore the application of Metamaterials to microstrip patch antennas. Thereafter, a transmission line based novel metamaterial antenna has been proposed for WiMAX (3.5 GHz) applications. For Wireless Local Area Network (WLAN) 5.8 GHz applications, a Complementary Split Ring Resonator (CSRR) loaded rectangular patch antenna is proposed. To realize simul-taneous dual band operations for Bluetooth (2.4 GHz) and for WLAN (5.8 GHz), a symmetric slot loaded antenna has been proposed. Also for simultaneous WiMAX (3.5 GHz) and WLAN (5.8 GHz) operation, a microstrip patch antenna has been developed. All the designes were optimized using Particle Swarm Optimization (PSO) technique in built in CST Microwave Studio V9. MATLAB codes have been developed to calculate some usefull parameters needed for the dissertation work. iii