Abstract
Nd(Mg0.4Zn0.1Sn0.5)O3 ceramics prepared by the conventional solid-state method have been investigated for application in inverted-L monopole antenna. B2O3 was selected as a liquid sintering aid to lower the sintering temperature of Nd(Mg0.4Zn0.1Sn0.5)O3 ceramics. It was found that the X-ray diffraction patterns of the Nd(Mg0.4Zn0.1Sn0.5)O3 ceramics exhibited no significant phase difference with 0.25 and 0.5 wt% B2O3 additive at different sintering temperatures. The maximum values of the dielectric constant and the quality factor (Q × f) can be obtained when the Nd(Mg0.4Zn0.1Sn0.5)O3 ceramics with 0.25 wt% B2O3 additive were sintered at 1400°C for 4 h. The temperature coefficient of resonant frequency (−65.2 ppm/°C) was measured for Nd(Mg0.4Zn0.1Sn0.5)O3 ceramics with 0.25 wt% B2O3 additive sintered at 1400°C for 4 h. The measurement result of inverted-L monopole antenna at 3.5 GHz was presented. With this technique, a 32.39% bandwidth (return loss < 10 dB) with a center frequency at approximately 3.55 GHz was successfully achieved.
Acknowledgment
The authors would like to thank the National Science Council of the R. O. C., Taiwan, for financially supporting this research under Contract No. NSC 99-2622-E-262-003-CC3.
Communicated by Dr. George W. Taylor