A miniaturized Microwave Bandpass Filter Based on Modified (Mg0.95Ca0.05)TiO3 Substrate
1 College of Bigdata and Information Engineering, Guizhou University, Guiyang, Guizhou 550025, China
2 Department of Physics and Electronics, Liupanshui Normal University, Liupanshui, Guizhou 553004, China
3 College of Electrical Information, Huanggang Normal University, Huanggang, Hubei 438000, China
* Corresponding author, email address: firstname.lastname@example.org
A microwave miniaturized bandpass filter using (Mg0.95Ca0.05)TiO3 (abbreviated as 95MCT hereafter) ceramic substrate is investigated in the present paper. The paper studies the sintering and microwave dielectric properties of Al2O3, La2O3 and SiO2 co-doped 95MCT. The XRD pattern shows that a secondary phase MgTi2O5 is easily segregated in 95MCT ceramic, however, through co-doping it can be effectively suppressed, and the microwave dielectric properties, especially, the Qf value can be significantly improved. Through optimizing the co-doping ratio of Al2O3, La2O3 and SiO2, the sintering temperature of 95MCT ceramic can be lowered by 80°C, and the microwave dielectric properties can reach Qf=61856GHz and εr=19.84, which indicates the modified 95MCT ceramic have a great potential application in microwave communication devices. Based on this, we also designed a miniaturized microwave bandpass filter (BPF) on modified 95MCT substrate. Through a full wave electromagnetic structure simulation, the results show that the center frequency of the BPF is 2.45GHz and the relative bandwidth is 4.09% with the insertion loss of less than 0.2dB in the whole bandpass.
Key words: microwave dielectrics / doping / secondary phase / Qf value / bandpass filter
© The Authors, published by EDP Sciences, 2016
This is an Open Access article distributed under the terms of the Creative Commons Attribution License 4.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.