volume | PIER Journals

Abstract

This paper addresses the issue of sidelobe imbalance due to spurious coupling in quasi-elliptic filters designed in groove gap waveguide (GGW) technology using TE₁₀₂ overmoded cavity based resonator to realize the cross coupling in the cascaded quadruplet topology. The filter is designed at 38 GHz with 750 MHz bandwidth (1.97% fractional bandwidth) to demonstrate its potential as a narrow-band, high-power output filter at mm-wave frequencies in next-generation high throughput satellites. The filter is designed for production yield avoiding any complex structures to realize the negative cross coupling and using an all-capacitive iris structure. Systematic studies have been performed to identify and mitigate the sidelobe imbalance issue, and a final design has been proposed with a very low (<1 dB) sidelobe imbalance. The measured results of the realized hardware closely match simulated ones. The proposed design configuration is an ideal filter option for next generation SATCOM applications as it provides benefits of narrowband symmetrical frequency response with low insertion loss, sharp near band rejection, and high-power handling capability along with the benefits of gap waveguide technology in terms of ease of fabrication, low passive intermodulation (PIM) level, and low sensitivity towards surface imperfections and misalignment issues.

1. Kildal, Per-Simon, E. Alfonso, A. Valero-Nogueira, and Eva Rajo-Iglesias, "Local metamaterial-based waveguides in gaps between parallel metal plates," IEEE Antennas and Wireless Propagation Letters, Vol. 8, 84-87, 2008.

2. Kildal, Per-Simon, "Three metamaterial-based gap waveguides between parallel metal plates for mm/submm waves," 2009 3rd European Conference on Antennas and Propagation, 28-32, Berlin, Germany, 2009.

3. Vicente, Carlos and Hans L. Hartnagel, "Passive-intermodulation analysis between rough rectangular waveguide flanges," IEEE Transactions on Microwave Theory and Techniques, Vol. 53, No. 8, 2515-2525, 2005.

4. Zaman, Ashraf Uz, Per-Simon Kildal, and Ahmed A. Kishk, "Narrow-band microwave filter using high-Q groove gap waveguide resonators with manufacturing flexibility and no sidewalls," IEEE Transactions on Components, Packaging and Manufacturing Technology, Vol. 2, No. 11, 1882-1889, 2012.

5. Kant, Rajni, Deepak Ghodgaonkar, Parthasarathi Samanta, Vineet Kumar Dad, and Praveen Kumar Ambati, "An optimum microwave filter design using groove gap waveguide technology for low-loss high-power applications at Ku and Q-band," 2023 IEEE Wireless Antenna and Microwave Symposium (WAMS), 1-5, Ahmedabad, India, 2023.

6. Alós, Esperanza Alfonso, Ashraf Uz Zaman, and Per-Simon Kildal, "Ka-band gap waveguide coupled-resonator filter for radio link diplexer application," IEEE Transactions on Components, Packaging and Manufacturing Technology, Vol. 3, No. 5, 870-879, 2013.

7. Zarifi, Davoud and Marziye Nasri, "Design of a Ku-band filter based on groove gap waveguide technology," Progress In Electromagnetics Research Letters, Vol. 76, 71-76, 2018.

8. Marini, Stephan, Miguel Ferrando-Rocher, Aitor Morales Hernández, Encarnación Gimeno Nieves, Alejandro Jorge López, and Vicente E. Boria, "Ka-band diplexer design based on half-mode groove gap waveguide," AEU --- International Journal of Electronics and Communications, Vol. 175, 155062, 2024.

9. Arezoomand, Masoud, Abbas Pirhadi, and Shokrollah Karimian, "Design and implementation of a Ku‐band cross‐coupled gap waveguide filter using non‐resonating negative coupling node," IET Microwaves, Antennas & Propagation, Vol. 12, No. 8, 1345-1351, 2018.

10. Al-Juboori, Bahaa, Yi Huang, D. Klugmann, M. Hussein, and J. Zhou, "Millimeter wave cross-coupled bandpass filter based on groove gap waveguide technology," 2017 10th UK-Europe-China Workshop on Millimetre Waves and Terahertz Technologies (UCMMT), 1-4, Liverpool, UK, 2017.

11. Rezaee, Morteza and Ashraf Uz Zaman, "Groove gap waveguide filter based on horizontally polarized resonators for V-band applications," IEEE Transactions on Microwave Theory and Techniques, Vol. 68, No. 7, 2601-2609, 2020.

12. Shu, Minjie, Wenxuan Wu, Qian Yang, Jianzhong Chen, Cheng Guo, and Anxue Zhang, "Compact filters based on dual‐mode gap waveguide cavities and 3D printing technology," Microwave and Optical Technology Letters, Vol. 65, No. 3, 727-732, 2023.

13. Xiu, Tao, Yuan Yao, Hang Jiang, Xiaohe Cheng, Caixia Wang, Bin Wang, Junsheng Yu, and Xiaodong Chen, "Design of a compact and low-loss E-band filter based on multilayer groove gap waveguide," IEEE Microwave and Wireless Components Letters, Vol. 31, No. 11, 1211-1214, 2021.

14. Farahani, Hossein Sarbandi and Wolfgang Bösch, "Ku-band gap waveguide filter with negative coupling structure," 2019 European Microwave Conference in Central Europe (EuMCE), 290-293, Prague, Czech, 2019.

15. Yao, Beini, Nengcai Huang, Gang Zhang, Xin Zhou, Jing Lu, Kam Weng Tam, Wenfei Zhang, and Wanchun Tang, "Dual‐band bandpass filter with high selectivity based on 3D printable groove gap waveguide," IET Microwaves, Antennas & Propagation, Vol. 17, No. 10, 827-831, 2023.

16. Kant, Rajni, Deepak Ghodgaonkar, Abhishek Jindal, Parthasarathi Samanta, Hitesh Modi, and Praveen Kumar Ambati, "Design of a quasi-elliptic filter in groove gap waveguide technology using overmoded cavity for low-loss high-power applications at Q-band," 2023 IEEE Microwaves, Antennas, and Propagation Conference (MAPCON), 1-5, 2023.

17. Valero-Nogueira, Alejandro, Esperanza Alfonso, Jose I. Herranz, and Per-Simon Kildal, "Experimental demonstration of local quasi-TEM gap modes in single-hard-wall waveguides," IEEE Microwave and Wireless Components Letters, Vol. 19, No. 9, 536-538, 2009.

18. Shaterian, Zahra, Ali K. Horestani, and Michal Mrozowski, "Design guidelines for microwave filters in gap waveguide technology," 2021 IEEE MTT-S International Microwave Filter Workshop (IMFW), 182-184, Perugia, Italy, 2021.

19. Thomas, J. Brian, "Cross-coupling in coaxial cavity filters-a tutorial overview," IEEE Transactions on Microwave Theory and Techniques, Vol. 51, No. 4, 1368-1376, 2003.

20. Rosenberg, Uwe, "Newplanar'waveguide cavity elliptic function filters," 1995 25th European Microwave Conference, Vol. 1, 524-527, 1995.

21. Cameron, Richard J., "General coupling matrix synthesis methods for Chebyshev filtering functions," IEEE Transactions on Microwave Theory and Techniques, Vol. 47, No. 4, 433-442, 1999.

22. Cameron, Richard J., "Advanced coupling matrix synthesis techniques for microwave filters," IEEE Transactions on Microwave Theory and Techniques, Vol. 51, No. 1, 1-10, 2003.

23. Ness, John B., "A unified approach to the design, measurement, and tuning of coupled-resonator filters," IEEE Transactions on Microwave Theory and Techniques, Vol. 46, No. 4, 343-351, 1998.

24. Kudsia, C., K. Ainsworth, and M. Odonovan, "Microwave filters and multiplexing networks for communications satellites in the 1980s," 8th Communications Satellite Systems Conference, 522, Orlando, FL, USA, 1980.

25. Morales-Hernández, Aitor, Miguel Á. Sánchez-Soriano, Miguel Ferrando-Rocher, Stephan Marini, Máriam Taroncher Calduch, and Vicente E. Boria, "Peak power handling capability in groove gap waveguide filters based on horizontally polarized resonators and enhancement solutions," IEEE Microwave and Wireless Components Letters, Vol. 32, No. 7, 859-862, 2022.

Mr. Rajni Kant

Dr. Deepak Ghodgaonkar

Dr. Abhishek Jindal

Dr. Parthasarathi Samanta

Dr. Hitesh Modi

Dr. Praveen Kumar Ambati