SIZE REDUCTION AND PERFORMANCE ENHANCEMENT OF PLANAR ANTENNAS FOR L-BAND APPLICATION

Abstract

High performance, compact size and low cost are the basic requirements of modem 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 (DGS), Electromagnetic Metamaterial structures and so on. Among these, Metamaterials are relatively new and the potential applications of these special classes of materials have drawn much attention in last few decades. Metamaterials firstly came into existence when V. G. Veselago introduced the concept of Left-Handed (LH) materials, materials which have Negative Refractive Index because of negative Permittivity and Permeability. These materials are not naturally occurring so a lot research is done to design and simulate such metamaterials which can be used for number of applications like thin resonators, filters and antennas. In antennas these materials are used to enhance its performance. It increases Directivity, Gain Radiated Power and reduces size to enhance the antenna performance. As of today world, size reduction in antenna have gained much of interest as to decrease the sizes of communicating devices like mobile and remote sensing etc.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 microstrip patch antenna for L-band (1.28 GHz) was designed. To obtain size reduction Modified Split Ring Resonator (SRR) metamaterial structure was used to make various metamaterial antennas with the size reduction of about 80 percent as of microstrip patch antenna of same frequency. All the designs were made with CST.