Abstract
In this paper, a new compact size microstrip lowpass filter (LPF) with a very sharp roll-off is presented to apply in the modern wireless networks. The proposed LPF is designed using the series main resonators with meandered lines based on inductor-capacitor (LC) equivalent circuit analysis. The main goal is to achieve maximum-sharp roll-off by maintaining a wide stopband bandwidth and high return loss (RL). The main resonator of the proposed filter is consisted of two meandered line hairpin resonators (MLHR), and a meandered line T-shaped resonator (MLTR). The designed suppressor is composed of two coupled radial stubs to create a wide stopband. Low return loss in the passband, which has been created by the main resonator, is resolved by the suppressor structure with high return loss. The measured results show a − 3 dB cut-off frequency of 1.93 GHz. The very sharp transition band starts at 1.93 to 1.97 GHz (from − 3 to − 20 dB). The stopband is from 1.97 to 19.9 GHz (with the suppression level of − 20 dB). Also, the total size of the proposed LPF is only 13.3 × 10.1 mm2.






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Moloudian, G., & Dousti, M. (2018). Design and fabrication of a compact microstrip lowpass-bandpass diplexer with high isolation for telecommunication applications. International Journal of RF and Microwave Computer-Aided Engineering, 28(5), e21248. https://doi.org/10.1002/mmce.21248.
Rezaei, A., Noori, L., & Mohammadi, H. (2019). Miniaturized quad-channel microstrip diplexer with low insertion loss and wide stopband for multi-service wireless communication systems. Wireless Networks, 25(6), 2989–2996.
Liu, S., Xu, J., & Xu, Z. (2015). Compact lowpass filter with wide stopband using stepped impedance hairpin units. Electronics Letters, 51(1), 67–69. https://doi.org/10.1049/el.2014.3673.
Wang, J., Xu, L., Zhao, J. S., Guo, Y. X., & Wu, W. (2015). Compact quasi-elliptic microstrip lowpass filter with wide stopband. Electronics Letters, 46(20), 1384–1385. https://doi.org/10.1049/el.2010.1569.
Jiang, Y., Wei, B., Heng, Y., Guo, X., & Cao, B. (2017). Compact superconducting lowpass filter with wide stopband. Electronics Letters, 53(14), 931–933. https://doi.org/10.1049/el.2017.0429.
Chen, X., Zhang, L., Peng, Y., Leng, Y., Lu, H., & Zheng, Z. (2014). Compact lowpass filter with wide stopband bandwidth. Microwave and Optical Technology Letters, 57(2), 367–371. https://doi.org/10.1002/mop.28853.
Lee, H., Jung, D., Ren, D., & Choi, J. H. (2018). L-section matching with notches and its application for composite lowpass filter with spurious signal suppression. Electronics Letters, 54(10), 636–638. https://doi.org/10.1049/el.2018.0588.
Chen, F., Li, R., Chu, Q., & Member, S. (2017). Ultra-wide stopband low-pass filter using multiple transmission zeros. IEEE Access, 5, 6437–6443. https://doi.org/10.1109/ACCESS.2017.2693344.
Hayati, M., Najafi, M., Shama, F., & Zarghami, S. (2019). Microstrip lowpass filter with ultra-wide stopband using folded structures. Frequenz, 73(5–6), 219–226. https://doi.org/10.1515/freq-2018-0237.
Hayati, M., & Shama, F. (2017). A compact lowpass filter with ultra wide stopband using stepped impedance resonator’. Radioengineering, 26(1), 269–274. https://doi.org/10.13164/re.2017.0269.
Ma, K., & Yeo, K. S. (2010). New ultra-wide stopband low-pass filter using transformed radial stubs. IEEE Transactions on Microwave Theory and Techniques, 59(3), 604–611. https://doi.org/10.1109/TMTT.2010.2095031.
Jiang, S., & Xu, J. (2017). Compact microstrip lowpass filter with ultra-wide stopband based on dual-plane structure. Electronics Letters, 53(9), 607–609. https://doi.org/10.1049/el.2017.0637.
Rekha, T. K., Abdulla, P., Jasmine, P. M., & Anu, A. R. (2020). Compact microstrip lowpass filter with high harmonics suppression using defected structures. AEU-International Journal of Electronics and Communications, 115, 153032. https://doi.org/10.1016/j.aeue.2019.153032.
Zhang, B., Li, S., & Huang, J. (2015). Compact lowpass filter with wide stopband using coupled rhombic stubs. Electronics Letters, 51(3), 264–266. https://doi.org/10.1049/el.2014.3490.
Velidi, V. K., & Sanyal, S. (2010). High-rejection wide-stopband lowpass filters using signal interference technique. International Journal of RF and Microwave Computer-Aided Engineering, 20(3), 253–258. https://doi.org/10.1002/mmce.20424.
Du, Z., Yang, H., Zhang, H., & Zhu, M. (2014). Compact lowpass filter with high suppression level and wide stopband using stepped impedance m-shape units’. Microwave and Optical Technology Letters, 56(12), 2947–2950. https://doi.org/10.1002/mop.28744.
Li, Q., Zhang, Y., Li, D., & Xu, K. (2016). Compact low-pass filters with deep and ultra-wide stopband using tri-and quad-mode resonators. IET Microwaves, Antennas and Propagation, 11(5), 743–748. https://doi.org/10.1049/iet-map.2016.0466.
Liu, S., Xu, J., & Xu, Z. (2015). Sharp roll-off lowpass filter using interdigital DGS slot. Electronics Letters, 51(17), 1343–1345. https://doi.org/10.1049/el.2015.0721.
Xiao, M., Sun, G., & Li, X. (2015). A lowpass filter with compact size and sharp roll-off. IEEE Microwave and Wireless Components Letters, 25(12), 790–792. https://doi.org/10.1109/LMWC.2015.2496801.
Kumar, K. V. P., & Karthikeyan, S. S. (2018). Microstrip lowpass filter with flexible roll-off rates. AEU-International Journal of Electronics and Communications, 86, 63–68. https://doi.org/10.1016/j.aeue.2018.01.025.
Aznar, F., Velez, A., Bonache, J., Menés, J., & Martin, F. (2019). Compact lowpass filters with very sharp transition bands based on open complementary split ring resonators’. Electronics Letters, 21, 733. https://doi.org/10.1049/el.2009.2854.
Velidi, V. K., & Sanyal, S. (2011). Sharp roll-off lowpass filter with wide stopband using stub-loaded coupled-line hairpin unit. IEEE Microwave and Wireless Components Letters, 21(6), 301–303. https://doi.org/10.1109/LMWC.2011.2132120.
Wang, J. P., Ge, L., Guo, Y.-X., & Wu, W. (2010). Miniaturised microstrip lowpass filter with broad stopband and sharp roll-off. Electronics Letters, 46(8), 573–575. https://doi.org/10.1049/el.2010.0329.
Li, J. L., Qu, S. W., & Xue, Q. (2009). Compact microstrip lowpass filter with sharp roll-off and wide stop-band. Electronics Letters, 45(2), 110–111. https://doi.org/10.1049/el:20093246.
Hayati, M., Zarghami, S., & Kazemi, A. H. (2018). Very sharp roll-off ultrawide stopband low-pass filter using modified flag resonator. IEEE Transactions on Components, Packaging and Manufacturing Technology, 8(12), 2163–2170. https://doi.org/10.1109/TCPMT.2018.2797211.
Vaezi, A., & Geran Gharakhili, F. (2017). Design and fabrication of microstrip lowpass filter using asymmetric hairpin resonator. International Journal of RF and Microwave Computer-Aided Engineering, 53(11), 734–735. https://doi.org/10.1002/mmce.21733.
Jiang, S., & Xu, J. (2017). Sharp roll-off planar lowpass filter with ultra-wide stopband up to 40 GHz. Electronics Letters, 53(11), 734–735. https://doi.org/10.1049/el.2017.1238.
Hong, J. S. G., & Lancaster, M. J. (2001). Microstrip filters for RF/microwave applications. New York: Wiley.
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Hayati, M., Zarghami, S. & Shama, F. Compact microstrip lowpass filter with very sharp roll-off using meandered line resonators. Wireless Netw 27, 1203–1213 (2021). https://doi.org/10.1007/s11276-020-02509-7
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DOI: https://doi.org/10.1007/s11276-020-02509-7