Optimization and performance analysis of probe-edge-inset and aperture feed patch antenna covered by dielectric superstrate

In this paper, the design of a microstrip patch antenna using superstrate layers for performance enhancement is presented. The proposed antenna is excited by using the edge, inset, probe and aperture feeding methods. Genetic Algorithm optimization technique has been utilized for the optimization of patch antenna dimensions. The double layer dielectric superstrate disposed above the patch antennas are used for enhancing the directivity and also for getting better return loss since microstrip antennas have limitations in directivity, gain and efficiency. The proposed antennas are simulated by using the Ansoft High Frequency Structure Simulator software. The characteristics of the edge, inset, probe and aperture feeding patch antennas covered by superstrate are obtained in terms of return loss, directivity, voltage standing wave ratio and radiation pattern and are compared with those of the same patch antennas without superstrate. We also carry out a parametric study of the distance between the lower and the higher superstrate, and examine how this separation distance affects the directivity and beam shaping of the composite structure. The return loss up to -47.06 dB and directivity equal to 13.5 dB are obtained at the center frequency of 8 GHz for the aperture coupled patch antenna through the use of the superstrate layers. This antenna is found to be suitable for X band applications.