BULK AND PATCH FERRITE RESONATOR ANTENNAS BASED ON THE CERAMIC MATRIX
COMPOSITE: GDIG(x)YIG(1-x)
MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, 51 (6):
1595-1602 (2009)DOI: 10.1002/mop.24395
Abstract
In this stuty, the dielectric properties of the GdIG(x)YIG(1-x) ferrite
composite material tit radio frequency (RF) and microwave frequency
hands 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 GdIG(0.5)YIG(0.5) 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 epsilon(r), tg delta(E), and mu(r) were obtained. (C)
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