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MICROWAVE DIELECTRIC PROPERTIES OF NI0.2CUXZN0.8-XFE2O4 FOR APPLICATION IN ANTENNA

By K. Mohit, V. R. Gupta, and S. K. Rout

Full Article PDF (797 KB)

Abstract:
Structural, vibrational and microwave dielectric properties of Nickel-Copper-Zinc ferrite (Ni0.2CuxZn0.8-xFe2O4) ceramics have been presented in this paper. Samples have been prepared using conventional auto-combustion method. The X-ray diffraction (XRD) results confirmed the ferrite samples to be of cubic spinel structure, which further was validated by Fourier transform infrared (FT-IR) and Raman spectroscopy. The relative permittivity (εr) increased from 7.474 to 8.132 with successive increase in Cu content. The observed and calculated permittivity using Clausius-Mossoitti relation have been in good agreement. The temperature coefficient of resonant frequency (τf) decreased from -75.85 ppm/°C to -32.12 ppm/°C with increase in successive Cu content. The relative permeability (μr) have been calculated by using the Nicholson-Ross-Weir conversion technique. Using Ni0.2Cu0.2Zn0.6Fe2O4 sample the ferrite resonator antennas have been designed in three different shapes. The experimental and theoretical characteristics of the antennas have been compared and a good agreement has been achieved.

Citation:
K. Mohit, V. R. Gupta, and S. K. Rout, "Microwave Dielectric Properties of Ni0.2CuXZn0.8-XFE2O4 for Application in Antenna," Progress In Electromagnetics Research B, Vol. 57, 157-175, 2014.
doi:10.2528/PIERB13090705

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