volume | PIER Journals

Abstract

Structural, vibrational and microwave dielectric properties of Nickel-Copper-Zinc ferrite (Ni_0.2Cu_xZn_0.8-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 (ε_r) 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 (τ_f) decreased from -75.85 ppm/°C to -32.12 ppm/°C with increase in successive Cu content. The relative permeability (μ_r) have been calculated by using the Nicholson-Ross-Weir conversion technique. Using Ni_0.2Cu_0.2Zn_0.6Fe₂O₄ 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.

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Dr. Kumar Mohit

Dr. Vibha Rani Gupta

Dr. Sanjeeb Kumar Rout