A Novel Expression in Calculating Resonant Frequency of H–Shaped Compact Microstrip Antennas Obtained by using Artificial Bee Colony Algorithm

Abstract

In this paper, a new, simple and accurate expression for the resonant length in calculating resonant frequency of H–shaped compact microstrip antennas at UHF frequencies applications is presented. H–shaped compact microstrip antennas with a range of different physical dimensions built on various substrates are numerically simulated with a software package based on finitedifference time domain method. A closed-form expression for the resonant length is constructed with the aid of both the artificial bee colony algorithm and the simulation data. The resonant frequency is then calculated by means of this resonant length expression. The average percentage error is found to be less than 0.79% for 216 simulated antennas. Experimental and simulated results reported elsewhere have been employed to illustrate the validity and accuracy of the present formulation.