The irregularly shaped patch as a perturbation of a regularly shaped patch

A rapid and accurate approach is developed to solve the response of an irregularly shaped patch. This approach is based on the observation that the actual irregularly shaped patch can usually be taken as a perturbation of a regularly shaped patch. The steps of the approach are: 1) ideal regular patch (square), 2) irregular patch (corner cut), 3) add fringe field perturbation, and 4) Cauchy's interpretation. Results with less than 0.3% error in resonant frequency are obtained. © 2002 John Wiley & Sons, Inc. Microwave Opt Technol Lett 32: 70–74, 2001.