In this paper, a compact microstrip wideband bandpass filter (BPF) based on square ring loaded resonator (SRLR) is proposed. The SRLR is formed by loading a pair of bent open-stubs outside the diagonal corners of a square ring, which generates three split degenerated modes. The first two split modes form a dominant wideband passband. By introducing another pair of loaded open-stubs, the third split mode is moved into the passband to achieve an extra bandwidth for the wideband passband. Measured results show that this proposed BPF has a 3 dB fractional bandwidth of 69%, and the insertion loss of the BPF is less than 1.0 dB.
Jian Zhong Chen,
Shou Jia Sun,
"Microstrip Wideband Bandpass Filter Based on Square Ring Loaded Resonator," Progress In Electromagnetics Research Letters,
Vol. 43, 175-184, 2013. doi:10.2528/PIERL13100805
1. Ren, S.-W., H.-L. Peng, J.-F. Mao, and A. M. Gao, "Compact quasi-elliptic wideband bandpass filter using cross-coupled multi-mode resonator," IEEE Microw. Wireless Compon. Lett., Vol. 22, No. 8, 397-399, 2012. doi:10.1109/LMWC.2012.2205230
2. Sohail, K., P.-W. Wong, and Y.-C. Lee, "Synthesis and design of four pole ultra-wide band (UWB) bandpass filter (BPF) employing multi-mode resonators (MMR)," IEEE MTT-S Int. Microw. Symp. Dig., 1-3, 2012.
3. Chen, C.-P., J. Oda, T. Anada, Z. Ma, and S. Takeda, "Theoretical design of wideband filters with attenuation poles using improved parallel-coupled three-line units," IEEE MTT-S Int. Microw. Symp. Dig., 1-3, 2012.
4. Amir, N., M. Masoud, and H. Ahmad, "A novel wideband stepped-impedance rectangular-ring resonator bandpass filter with two notched bands," IEEE MTT-S Int. Microw. Symp. Dig., 1-3, 2012.
5. Chen, D., L. Zhu, and C.-H. Cheng, "A novel wideband bandpass filter using stub-loaded ring resonator and tapped feed," Progress In Electromagnetics Research Letters, Vol. 42, 37-44, 2013.
6. Cao, H.-L., S.-J. He, H. Li, and S.-Z. Yang, "A compact wideband bandpass filter using novel CSRR loaded QMSIW resonator with high selectivity," Progress In Electromagnetics Research C , Vol. 41, 239-254, 2013.
7. Wei, F., Z.-D. Wand, F. Yang, and X.-W. Shi, "Compact UWB BPF with triple-notched bands based on stub loaded resonator," Electron. Lett., Vol. 49, No. 2, 124-126, 2013. doi:10.1049/el.2012.2885
8. Deng, K., J.-Z. Chen, B. Wu, T. Su, and C.-H. Liang, "Miniaturized wideband bandpass filter utilizing square ring resonator and loaded open-stub," Progress In Electromagnetics Research C, Vol. 39, 179-192, 2013.
9. Sun, S. and L. Zhu, "Wideband microstrip ring resonator bandpass filters under multiple resonances," IEEE Trans. Microw. Theory Tech., Vol. 55, No. 10, 2176-2182, 2007. doi:10.1109/TMTT.2007.906510
10. Ahonnom, S. and P. Akkaraekthalin, "Wideband dual mode microstrip bandpass filters using a new perturbation with notch rectangular slots," Proceeding of ECTI-CON, Vol. 1, 269-272, 2008.
11. Kim, C.-H. and K. Chang, "Wideband ring resonator bandpass filter with dual stepped impedance stubs," IEEE MTT-S Int. Microw. Symp. Dig., 229-232, 2010.
12. Fan, J., D.-Z. Zhan, C.-J. Jin, and J.-R. Luo, "Wideband microstrip bandpass filter based on quadruple mode ring resonator," IEEE Microw. Wireless Compon. Lett., Vol. 22, No. 7, 348-350, 2012. doi:10.1109/LMWC.2012.2199977
13. Ma, Z.-W., H. Sasaki, C.-P. Chen, T. Anada, and Y. Kobayashi, "Design of a wideband bandpass filter using microstrip parallel-coupled dual-mode ring resonator," Asia-Pacific Microwave Conference Proceedings, 21-24, 2010.
14. Srisathit, K., A. Worapishet, and W. Surakampontorn, "Design of tripple-mode ring resonator for wideband microstrip bandpass filters," IEEE Trans. Microw. Theory Tech., Vol. 58, No. 11, 2867-2877, 2010. doi:10.1109/TMTT.2010.2078295
15. Deng, K., S. Yang, S.-J. Sun, B. Wu, and X.-W. Shi, "Dual-mode dual-band bandpass filter based on square loop resonator," Progress In Electromagnetics Research C, Vol. 37, 119-130, 2013.