Effect of Dielectric Superstrate Thickness on the Characteristics of Rectangular Patch Antenna

V. Saidulu Department of Electronics and Communication, MGIT,Hyderabad, AP, India [email protected] K. Kumarswamy, Department of Electronics and Communication, BIET,Hyderabad, AP, India [email protected] K. Srinivasa Rao Department of Electronics and Communication, VIF, Hyderabad, AP, India P.V.D. Somasekhar Rao Department of Electronics and Communication, JNTUH,Hyderabad,AP,India , Abstract: This paper focused about the coaxial probe fed rectangular patch of microstrip antenna characteristics have been studied with and without dielectric Superstrate. The dielectric constant of the substrate and Superstrate material is used same for designing of rectangular microstrip patch antenna. The antenna designed frequency is 2.4GHz(ISM band) using transmission line model. In this paper experimentally investigated the effect of single microstrip patch antenna(without Superstrate) and varying various thicknesses of Superstrate (radome) and same dielectric constant of the substrate on the patch antenna studied on the parameters such as bandwidth, beam-width, gain, resonant frequency, input impedance, return-loss and VSWR etc. Measured results shows when placing the Superstrates material thickness 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 thickness. 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. Impedance characteristics are that both input impedance and the reactance which are increased as Superstrate become thick and its ∈ increases.