2019-02-12
Ceramic Waveguide Filters with Wide Spurious-Free Stopband Response
By
Progress In Electromagnetics Research M, Vol. 79, 23-31, 2019
Abstract
This work proposes new filter design techniques to improve the out of band spurious performance of integrated ceramic waveguide filters and ceramic loaded filters. Various resonators of different types like non-uniform width, TEM and half ridge were used. The proposed filter designs offer a considerable miniaturization and significantly improved spurious performance up to 85% without compromising the figure of merits of the filters like Q-factor, return loss, etc. Two sixth order filters with best in-band and out-band performance have been fabricated. Measured results of the fabricated filters are in good agreement with the computer simulations, which confirm the validity and accuracy of designs.
Citation
Sharjeel Afridi, Ian Hunter, and Yameen Sandhu, "Ceramic Waveguide Filters with Wide Spurious-Free Stopband Response," Progress In Electromagnetics Research M, Vol. 79, 23-31, 2019.
doi:10.2528/PIERM18120703
References

1. Chi, W., K. A. Zaki, A. E. Atia, and T. G. Dolan, "Dielectric combline resonators and filters," IEEE Transactions on Microwave Theory and Techniques, Vol. 46, 2501-2506, 1998.
doi:10.1109/22.739240        Google Scholar

2. Walker, V. and I. C. Hunter, "Design of cross-coupled dielectric-loaded waveguide filters," IEE Proceedings - Microwaves, Antennas and Propagation, Vol. 148, 91-96, 2001.
doi:10.1049/ip-map:20010332        Google Scholar

3. Cohn, S. B., "Microwave bandpass filters containing high-Q dielectric resonators," IEEE Transactions on Microwave Theory and Techniques, Vol. 16, No. 4, 218-227, April 1968. doi: 10.1109/TMTT.1968.1126654.
doi:10.1109/TMTT.1968.1126654        Google Scholar

4. Nishikawa, T., "Microwave ceramic dielectrics and their applications," 1988 18th European Microwave Conference, 70-80, 1988.
doi:10.1109/EUMA.1988.333799        Google Scholar

5. Salehi, A., R. K. Reddy, T. Lukkarila, and S. Amir, "Spurious suppression of dielectric filters in practical wireless systems," 2008 IEEE MTT-S International Microwave Symposium Digest, 1087-1090, 2008.
doi:10.1109/MWSYM.2008.4633245        Google Scholar

6. Sandhu, M. Y. and I. C. Hunter, "Miniaturized dielectric waveguide filters," International Journal of Electronics, Vol. 103, 1776-1787, Oct. 2, 2016.        Google Scholar

7. Hunter, I. C. and M. Y. Sandhu, "Monolithic integrated ceramic waveguide filters," 2014 IEEE MTT-S International Microwave Symposium (IMS 2014), 1-3, 2014.        Google Scholar

8. Riblet, H. J., "Waveguide filter having nonidentical sections resonant at same fundamental frequency and different harmonic frequencies,", 1964.        Google Scholar

9. Morelli, M., I. Hunter, R. Parry, and V. Postoyalko, "Stop-band improvement of rectangular waveguide filters using different width resonators: selection of resonator widths," 2001 IEEE MTTS International Microwave Sympsoium Digest (Cat. No.01CH37157), Vol. 3, 1623-1626, 2001.
doi:10.1109/MWSYM.2001.967215        Google Scholar

10. Rezaiesarlak, R., P. Loghmannia, and M. Salehi, "Miniaturized waveguide filter with improved stop-band response," Microwave and Optical Technology Letters, Vol. 56, 512-515, Feb. 1, 2014.        Google Scholar

11. Morelli, M., I. Hunter, R. Parry, and V. Postoyalko, "Stopband performance improvement of rectangular waveguide filters using stepped-impedance resonators," IEEE Transactions on Microwave Theory and Techniques, Vol. 50, 1657-1664, 2002.
doi:10.1109/TMTT.2002.800381        Google Scholar

12. Borowiec, R., "Dielectric resonator filters," 2014 20th International Conference on Microwaves, Radar and Wireless Communications (MIKON), 1-4, 2014.        Google Scholar

13. Chi, W., K. A. Zaki, A. E. Atia, and T. Dolan, "Conductor loaded resonator filters with wide spurious free stop band," 1997 IEEE MTT-S International Microwave Symposium Digest, Vol. 2, 1079-1082, 1997.        Google Scholar

14. Weily, A. R. and A. S. Mohan, "Mixed combline and He/sub 11/mode dielectric resonator filter with improved spurious performance," Proceedings of 1997 Asia-Pacific Microwave Conference, Vol. 2, 805-808, 1997.
doi:10.1109/APMC.1997.654664        Google Scholar

15. Matthaei, G. L., L. Young, and E. M. T. Jones, Microwave Filters, Impedance-Matching Networks, and Coupling Structures, Artech House Books, 1980.

16. Afridi, S., M. Sandhu, N. Somjit, and I. Hunter, "Monolithic ceramic waveguide filter with wide spurious free bandwidth," 2016 46th European Microwave Conference (EuMC), 241-244, 2016.
doi:10.1109/EuMC.2016.7824323        Google Scholar

17. Sebastian, M. T., Dielectric Materials for Wireless Communication, Elsevier Science, 2010.

18. Hunter, I. and I. O. E. Engineers, Theory and Design of Microwave Filters, Institution of Engineering and Technology, 2001.
doi:10.1049/PBEW048E

19. Afridi, S., M. Sandhu, and I. Hunter, "Mixed non-uniform width/evanescent mode ceramic resonator waveguide filter with wide spurious free bandwidth," 2016 IEEE MTT-S International Conference on Numerical Electromagnetic and Multiphysics Modeling and Optimization (NEMO), 1-3, 2016.        Google Scholar

20. Hunter, I., S. Afridi, and M. Sandhu, "Integrated ceramic waveguide filters with improved spurious performance," 2015 European Microwave Conference (EuMC), 674-677, 2015.
doi:10.1109/EuMC.2015.7345853        Google Scholar

21. Afridi, S., I. Hunter, and M. Y. Sandhu, "Spurious Free Non Uniform Width Dielectric Loaded Filters," 2018 48th European Microwave Conference (EuMC), 85-88, 2018.
doi:10.23919/EuMC.2018.8541792        Google Scholar