Cad formulas for patch dimensions of rectangular microstrip antennas with various substrate thicknesses

This letter presents the closed from formulas for determining the patch dimensions of electrically thin and thick rectangular microstrip antennas. The presented formulas constructed by utilizing a differential evolution algorithm become very useful as computer-aided design (CAD) models for patch antenna design. A comparison between the calculated and experimental results derived tom 33 patch antennas demonstrates that the proposed CAD formulas provide <0.16% and 0.22% errors on average for the patch length and patch width, respectively. The results obtained by using the formulas given here are found to be closer to the experimental values, as compared with previous results presented by several researchers. (C) 2007 Wiley Periodicals, Inc.