In this paper, a method of designing a SIW (Substrate Integrated Waveguide) bandpass filter with high selectivity is proposed. Four resonant cavities of the proposed filter are arranged in straight line. The microstrip gradient line is directly fed into the cavities. Two U-shaped slots are etched on the top face of each cavity which will result in the resonant modes reduced and the high modes of SIW cavity pushed far away from the dominant resonant mode. Thus the filter will have both the features of compact size and wide stopband. The center frequency of the filter is designed at 5.2 GHz. The measured results are highly matched with the simulated ones.
"Design of Compact SIW Bandpass Filter with High Selectivity," Progress In Electromagnetics Research Letters,
Vol. 112, 35-40, 2023. doi:10.2528/PIERL23071003
1. Yang, Z., Z. Wang, J. Dong, Y. Liu, and T. Yang, "Compact wideband HMSIW bandpass filter with defected ground structure," 2015 IEEE International Conference on Signal Processing, Communications and Computing (ICSPCC), 1-4, Ningbo, China, 2015.
2. Jin, B., P. Zhang, J. Mu, M. Zhang, and M. Li, "A miniaturized bandpass filter basing on HMSIW loaded dual-mode CSRR," 2021 IEEE MTT-S International Wireless Symposium (IWS), 1-3, Nanjing, China, 2021.
3. Pelluri, S., M. Fasil, and M. Kartikeyan, "Compact bandpass filter using QMSIW cavity with slot resonator," 2019 International Conference on Electrical, Electronics and Computer Engineering (UPCON), 1-4, Aligarh, India, 2019.
4. Zheng, Y., Y. Zhu, Z. Wang, and Y. Dong, "Compact, wide stopband, shielded hybrid filter based on quarter-mode substrate integrated waveguide and microstrip line resonators," IEEE Microwave and Wireless Components Letters, Vol. 31, No. 3, 245-248, Mar. 2021. doi:10.1109/LMWC.2020.3049048
5. Dong, Y., C.-T.-M. Wu, and T. Itoh, "Miniaturised multi-band substrate integrated waveguide filters using complementary split-ring resonators," IET Microw., Antennas Propag., Vol. 6, No. 6, 611-620, 2012. doi:10.1049/iet-map.2011.0448
6. Salim, A. J., A. N. Alkhafaji, T. A. Elwi, H. T. Ziboon, S. Mutashar, and J. K. Ali, "Miniaturized SIW wideband BPF based on folded ring and meander line slot for wireless applications," 2017 Second Al-Sadiq International Conference on Multidisciplinary in IT and Communication Science and Applications (AIC-MITCSA), 136-139, Baghdad,.
7. Zhang, H., W. Kang, and W. Wu, "Miniaturized dual-band SIW filters using E-shaped slotlines with controllable center frequencies," IEEE Microwave and Wireless Components Letters, Vol. 28, No. 4, 311-313, Apr. 2018. doi:10.1109/LMWC.2018.2811251
8. Zhu, Y. and Y. Dong, "Stripline resonator loaded compact SIW filters with wide suppression and flexible response," IEEE Microwave and Wireless Components Letters, Vol. 30, No. 5, 465-468, May 2020. doi:10.1109/LMWC.2020.2982773
9. Azad, A. R. and A. Mohan, "Substrate integrated waveguide dual-band and wide-stopband bandpass filters," IEEE Microwave and Wireless Components Letters, Vol. 28, No. 8, 660-662, Aug. 2018. doi:10.1109/LMWC.2018.2844103
10. Jia, D., Q. Feng, Q. Xiang, and K. Wu, "Multilayer substrate integrated waveguide (SIW) filters with higher-order mode suppression," IEEE Microw. Wireless Compon. Lett., Vol. 26, No. 9, 678-680, Sep. 2016. doi:10.1109/LMWC.2016.2597222
11. Li, R., X. Tang, and F. Xiao, "Design of substrate integrated waveguide transversal filter with high selectivity," IEEE Microw. Compon. Lett., Vol. 20, No. 6, 328-330, Jun. 2010. doi:10.1109/LMWC.2010.2047518
12. Khan, A. A. and M. K. Mandal, "Narrowband substrate integrated waveguide bandpass filter with high selectivity," IEEE Microwave and Wireless Components Letters, Vol. 28, No. 5, 416-418, May 2018. doi:10.1109/LMWC.2018.2820605
13. Yun, T.-S., et al., "Harmonics suppressed substrate-integrated waveguide filter with integration of low-pass filter," Microw. Opt. Technol. Lett., Vol. 50, No. 2, 447-450, Feb. 2008. doi:10.1002/mop.23114
15. Chu, P., L. Guo, L. Zhang, F. Xu, W. Hong, and K. Wu, "Wide stopband substrate integrated waveguide filter implemented by orthogonal ports' offset," IEEE Transactions on Microwave Theory and Techniques, Vol. 68, No. 3, 964-970, Mar. 2020. doi:10.1109/TMTT.2019.2947894
16. Wu, Y. D., G. H. Li, W. Yang, and X. X. Yang, "Design of compact wideband QMSIW band-pass filter with improved stopband," Progress In Electromagnetics Research Letters, Vol. 65, 75-79, 2017. doi:10.2528/PIERL16110301