Circuit Theory Analysis of Aperture Coupled Patch Antenna for Wireless Communication

An analysis of dual band aperture coupled microstrip patch antenna is performed using modal expansion cavity model. The theoretical investigation of antenna characteristics such as return loss, VSWR and radiation pattern is represented. The influence of geometric parameters of the aperture coupled microstrip patch antenna, such as aperture length and width, height of the substrate, dielectric constant are also investigated. It is found that antenna resonates at two distinct modes i.e. 4.39 and 5.55 GHz for lower and upper resonance frequencies respectively. The bandwidth of the aperture coupled microstrip patch antenna at lower resonance frequency is 10.23% (theoretical) and 13.33% (simulated) whereas at upper resonance frequency, it is 5.69% (theoretical) and 3.59% (simulated). The frequency ratio obtained for upper to lower resonance frequencies for theoretical and simulated results are 1.5 and 1.37 respectively. The theoretical results are compared with IE3D simulation results along with reported experimental results and they are in close agreement.