A new microwave dielectric resonator Ba(Tb1/2Nb1/2)03 has been prepared and characterized in the microwave frequency region. 1 wt% CeO2 is used as additive to reduce the sintering temperature. The sintered samples were characterized by XRD, SEM and Raman spectroscopic methods. Microwave DR properties such as er, Q factor and temperature-coefficient of resonant frequency (Ti) have been measured using a HP 8510 B Network Analyzer. Cylindrical DRs of Ba(Tb1/2Nbi/2)03 showed high Er (~ 37), high Q (~3,200) and low Tf (~10 ppm /°C) at 4 GHz and hence are useful for practical applications
Supriyo,Dey; Aanandan,C K; Mohanan,P; K G Nair(IETE Technical Review, 1993)
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Abstract:
Design, development and experimental observations of a L: band printed dipole antenna is presented.Bandwidth
enhancement is achieved by end-loading or the dipole arms. Using the present technique Impedance bandwidth van be
enhanced up to 50% without degrading the efficiency of the antenna.
Mailadil,Sebastian T; Sam,Solomon; Ravindran,Ratheesh(Regional Research Laboratory, April , 1999)
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Abstract:
Microwave ceramic dielectric resonators (DRs) based on RETiNbO6
(RE = Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Y, and Yb)
have been prepared using the conventional solid -state ceramic
route. The DR samples are characterized using XRD and SEM
methods. The microwave dielectric properties are measured
using resonant methods and a net work analyzer . The ceramics
based on Ce, Pr, Nd, and Sin have dielectric constants in the
range 32-54 and positive coefficient of thermal variation of
resonant frequency (r,). The ceramics based on Gd, Tb, Dy, Y.
and Yb have dielectric constants in the range 19-22 and
negative Tf