Performance Analysis of Circular Microstrip Patch Antenna With Dielectric Superstrates

This paper demonstrates, the effect of dielectric superstrates on the performance of coaxial probe fed circular patch microstrip antenna with and without dielectric superstrates. The antenna can be designed at 2.4 GHz(ISM band) frequency and fabricated on Arlon diclad substrate, whose dielectric constant ( is 2.2. The theoretical formulation has been studied using cavity model analysis. In this paper experimentally studied the effect of dielectric superstrates on the parameters such as bandwidth, beam-width, gain and resonant frequency, input impedance, VSWR, return-loss etc. Measured results shows when placing the superstrate material above the substrate the antenna parameter will be changed and antenna resonant frequency will be shifted lower side, while other parameters have slight variation in their values. In particular, the resonant frequency increases with the dielectric constant of the superstrates. In addition, it has also been observed that return loss and VSWR increases, however bandwidth and gain decreases with the dielectric constant of the superstrates.