Design and Development of Fractal Aperture Coupled Microstsrip Patch Antenna for Wireless Applications

Abstract

The wireless industry has undergone a volatile emergence today in present era. Antenna the most important component of wireless system demand versatility and unobtrusiveness. Need of multiband antennas are increasing day by day due to need of covering maxinum applications. Fractal plays a prominent role for these requirements. Fractals have non-integral dimensions and their space filling capability could be used for miniaturing antenna size and their properties of self similarity in the geometry leads to have antennas which has more number of resonant frequencies. Fractal geometries when applied to UWB generator patch, improves gain, return loss and radiation characteristics. Often fractal antennas does not require any matching components to achieve multiband or broadband performance. Thus the research work presented here in thesis focuses on the design and simulation of a plus shped carpet fractal antenna, koch aperture coupled fractal antenna, complementary bowtie aperture coupled antenna and a cup shaped microstrip line fed antenna using CST(Computer Simulation software) microwave studio version 2014. The antennas are fed using aperture coupled feeding mechanism because it provides reasonably higher bandwidth as compared to other feeds and a moderate amount of spurious radiations A plus shaped carpet fractal antenna covers the frequency band ranging from 3.9-4.08 GHz, 4.8-5.06 GHz, 6.1-6.4 GHz, 6.93-11.39 GHz with adequate bandwidth of 180 MHz, 260 MHz, 300 MHz and 4460 MHz respectively. Koch fractal aperture coupled antenna covers the frequency band ranging from 5.3-9.2 GHz with adequate bandwidth of 3900 MHz resonating at 6.9 GHz, 8.0 GHz and 8.4 GHz respectively. Complementary bowtie antenna covers frequency range from 4.08-6.2 GHz with impedance bandwidth of 2120 MHz. A cup shaped fractal antenna covers the frequency range from 4.9-25.9 GHz with bandwidth of 21 GHz. In order to verify the antenna application in the practical scenario, plus shaped carpet fractal and bowtie aperture coupled antennas are fabricated using photolithography process and tested on a VNA and measured results are quite matching with simulated ones allowing the antenna to be suitable for WLAN, WiMAX, WIBAN, HIPERLAN, UWB, radio communication, satellite communication, radar communication applications.