A wideband dual-mode band-pass filter (BPF) is proposed and implemented using a vertically stacked double-ring resonator (VSDR) and a pair of broadside-coupled input/output (I/O) feeding lines based on a 4-layer low temperature cofired ceramic (LTCC) substrate. The proposed BPF is required to cover the fifth generation (5G) N77/N78/N79 band (3.3-5 GHz), thus achieves a fractional bandwidth (FBW) of 40%. Furthermore, the proposed structure not only possesses a non-orthogonal I/O feeding style for convenient interconnection with neighboring devices, but also removes disturbing element for simpler layout. Comparison and discussion are implemented as well.
2. Shin, K. R. and K. Eilert, "Compact low cost 5G NR N78 band pass filter with silicon IPD technology," Proc. 2018 IEEE 19th Wireless and Microwave Technology Conference (WAMICON), 1-3, 2018.
3. Zhou, B., C. H. Cheng, L. Yan, N. Zhou, Y. Cao, Q. Tang, and Z. Wang, "Wide upper stopband and nonorthogonal I/O feed dual-mode LTCC filter," Proc. 2016 IEEE IEEE International Symposium on Radio-Frequency Integration Technology (RFIT), 1-3, 2016.
4. Kuo, M. H., T. Y. Huang, H. Y. Tsai, C. X. Chen, and R. B. Wu, "A miniaturized bandpass filter using double folded dual-mode cavity resonators in LTCC," Proc. 2015 Asia-Pacific Microwave Conference (APMC), Vol. 3, 1-3, 2015.
5. Rodrıguez-Meneses, L. A., C. Gutierrez-Martınez, R. S. Murphy-Arteaga, J. Meza-Perez, and J. A. Torres-Fortiz, "Wideband dual-mode microstrip resonators as IF filters in a K-band wireless transceiver," Microwave and Optical Technology Letters, Vol. 62, 606-614, 2020.
6. Chen, C.-H. and K.-H. Lin, "Novel compact chip design of 5 GHz LTCC dual mode 4 poles quasi-elliptic resonator filter," Proc. 2007 Asia-Pacific Microwave Conference, 1-4, 2007.
7. Ahn, K., M. Uhm, and I. Yom, "New circular-shaped dual-mode cavity for mm-wave filters using LTCC technology," Proc. 2007 IEEE Antennas and Propagation Society International Symposium, 2104-2107, 2007.
8. Zhao, F. L., M. H. Weng, C. Y. Tsai, R. Y. Yang, H. Z. Lai, and S. K. Liu, "A miniaturized high selectivity band-pass filter using a dual-mode patch resonator with two pairs of slots," Microwave and Optical Technology Letters, Vol. 62, No. 3, 1145-1151, 2020.
9. Ji, X.-B. and M. Yang, "Compact balanced bandpass filter with high selectivity based on two coupled dual-mode microstrip loop resonators," Progress In Electromagnetics Research Letters, Vol. 90, 143-149, 2020.
10. Rezaee, M. and A. R. Attari, "Analytical synthesis of coupling matrix for a dual mode dual band filter," Microwave and Optical Technology Letters, Vol. 59, No. 1, 80-83, 2017.
11. Zhan, Y., J. Chen, and H. Tang, "Miniaturized LTCC bandpass filter using transmission line dual-mode resonator," Proc. 2014 IEEE International Workshop on Electromagnetics (iWEM), 22-23, 2014.
12. Chang, K., Microwave Ring Circuits and Antennas, John Wiley & Sons, Inc., New York, 1996.
13. Microwave Office, Applied Wave Research Corporation, , El Segundo, CA.
14. AXIEM, Applied Wave Research Corporation, , El Segundo, CA.