Bulk and patch ferrite resonator antennas based on the ceramic matrix composite: GdIG_x YIG_1‐x

Abstract

In this study, the dielectric properties of the GdIGXYIG1–X ferrite composite material at radio frequency (RF) and microwave frequency bands were studied. These measurements were carried out in different sample geometries: thick films and cylindrical ceramic bulk ferrite resonator. In the RF range, we observed that the material is rather stable because of its short changes as a function of temperature and frequency range. The temperature capacitance coefficient values for all the samples (thick films and cylindrical ceramic bulk samples) presented short positive values at the RF range. The GdIG0.5YIG0.5 thick film was used as a substrate for the microstrip antenna device, where the upper Ag electrode served as a circular patch antenna and a microstrip line was used as a feed line. The microstrip antenna operates in this configuration at 8.185 GHz. In the study of the dielectric properties of the composites antenna geometry, with the same ferrite composite, a bulk cylindrical geometry was investigated. A numerical study, together with the experimental, was done, and the dielectric characteristics of the composite like ϵr, tgδE, and μr were obtained. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 1595–1602, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24395

CPW-Fed Body Worn Monopole Antenna on Magneto-Dielectric Substrate in C-Band

“…Magnetic materials also provide miniaturization of the antenna and miniaturization factor n = √ ε r μ r , where ε r and μ r are real part of complex permittivity and permeability of the substrate material, respectively [12][13][14][15][16][17]. Bulk ferrites are rigid and have high magnetic loss at microwave frequencies which deteriorates the performance of the antenna [18][19][20]. Magneto-dielectric (MD) substrate material with nano ferrites inclusions in polymer matrix can be considered as an alternate substrate material [12,13,[21][22][23][24][25][26][27][28].…”