In touch non-destructive superstrate technique for estimating complex permittivity of nanocomposites

A study has been conducted to estimate the dielectric constants along with loss factors of different volume fractions of magnetodielectric composites with CoFe₂O₄ ferrite nano inclusions using a in touch nondestructive superstrate technique. This study also includes designing of microstrip patch antennas with magnetodielectric composite (MDC) covers. A microstrip patch antenna has been designed with rectangular patch using transmission line model and the resonant frequency change has been studied to estimate the dielectric properties. The fractional frequency change due to different magnetodielectric overlays has been estimated. Structural and surface morphologies have been studied using X-Ray diffraction (XRD) and Scanning electron microscopy (SEM). The real part of permittivity is found to vary from ~1-3 and dielectric loss is found to be of the order of ~10^-3 with increase in ferrite inclusions in the composite. Effective permittivity of the MDC with nano inclusions is less than the host matrix for smaller volume fractions.