STUDIES ON SPECIFIC STACKED MICROSTRIP PATCH ANTENNAS FOR DUAL-BAND APPLICATIONS

Abstract

In. this .dissertation work certain geometries of stacked microstrip patch antennas have been studied for dual-band wireless applications. In the first geometry, U-shaped slots were excoriated from both the top and bottom patch surfaces of the stacked antenna. This antenna was then driven by both probe feeding and CPW feeding. Parametric study of this new antenna was done for both the feeding mechanisms which gave an insight into the dual band behavior exhibited by the antennas. Further, the antennas were optimized for both the feeding mechanisms independently using Particle Swarm Optimization (PSO) to meet the bandwidth requirements of specific wireless applications. Moreover for the second geometry, fractal-shaped defects were excoriated from both the patch surfaces of the stacked antenna. Two antennas were designed based on this geometry, one based on Koch-shaped fractal defects and the other based on Minkowski-shaped fractal defects. Parametric analysis of the two antennas was done which gave an insight into the dual band behavior exhibited by the antennas. Further, the antennas were optimized using Particle Swarm Optimization (PSO) to meet the bandwidth requirements of specific wireless applications. Further, the fabrication of these antennas was carried out and the measured results were found to be in good agreement with the simulated results. The antenna operations conform to the IEEE approved 802.11b and 802.11a ISM standards for WLAN applications.