Design, testing and assembly of rectangular patch antenna

Abstract

One of humankind’s greatest natural resources is the electromagnetic spectrum and the antenna has been instrumental in harnessing this resource. The aim of the thesis is to Design and fabricate a coaxial fed rectangular Microstrip Antenna and study the effect of antenna dimensions Length (L), Width (W) and substrate parameters relative Dielectric constant (rε), substrate thickness on Radiation parameters of Band width and Beam width. A Microstrip antenna consists of conducting patch on a ground plane separated by dielectric substrate. Low dielectric constant substrates are generally preferred for maximum radiation. The conducting patch can take any shape but rectangular and circular configurations are the most commonly used configuration. Other configurations are complex to analyze and require heavy numerical computations. A Microstrip antenna is characterized by its Length, Width, Input impedance, and Gain and radiation patterns. The length of the antenna is nearly half wavelength in the dielectric; it is a very critical parameter, which governs the resonant frequency of the antenna. In view of design, selection of the patch width and length are the major parameters. The dielectric constant (permittivity) plays a major role in the overall performance of a patch antenna. It affects both the width, in turn the characteristic impedance and the length resulting in an altered resonant frequency. The Bandwidth of the patch antenna depends largely on the permittivity (εr) and thickness of the dielectric substrate. Ideally, a thick dielectric, lower permittivity (εr), low insertion loss is preferred for broadband purposes. Desired Patch antenna design is initially simulated by using IE3D simulator. And Patch antenna is realized as per design requirements. From the result I observed that the experimental antenna parameters are coinciding with simulated results. Beam width of a Microstrip element can be increased by choosing a smaller element, thus reducing W and L. For given resonant frequency, these dimensions may be changed by selecting a substrate having a higher relative permittivity.