Compact dual-band microstrip absorptive (reflectionless) bandstop filter design

Abstract

In this study, designs of dual-band microstrip absorptive (reflectionless) bandstop filters are represented by simulation and experimental studies. Absorptive bandstop filter responses are obtained by adding resistors to the third order bandstop filter designed by loading open circuit meandered stubs to the transmission line connected to the input and output ports. The designed absorptive bandstop filters have low reflection loss at the input port. Reflectionless bandstop filter design can be realized by adding a resistor to the open circuit stub near the input port. In this type of filter, depending on the position of the resistor, bandstop filter with only first or only second absorptive stopband can be designed. The dual-band bandstop filter response having two absorptive stopbands can be obtained by adding two resistors to the stub located near the input port and to the open circuit stub located in the middle. Three dual-band bandstop filters having first absorptive stopband, second absorptive stopband and two absorptive stopbands were fabricated and measured. The center frequencies of the stopbands were measured at 1.18 GHz and 3.5 GHz. The measured results have been obtained in a very good agreement with the simulations.

Keywords

• Absorptive (reflectionless)
• Bandstop
• Microstrip filter

Kompakt çift bantlı mikroşerit soğurucu (yansımasız) bant durduran filtre tasarımı

Öz

Bu çalışmada çift bantlı mikroşerit soğurucu (yansımasız) bant durduran filtre tasarımları, simülasyon ve deneysel çalışmalarla sunulmaktadır. Giriş ve çıkış portlarına bağlı iletim hattına açık devre kıvrımlı saplamalar yüklenerek tasarlanan üçüncü dereceden bant durduran filtreye dirençler eklenerek soğurucu bant durduran filtre cevapları elde edilmektedir. Tasarlanan soğurucu bant durduran filtreler giriş portunda düşük yansıma katsayısına sahiptir. Giriş portu yakınındaki açık devre saplamaya sadece birine direnç eklenerek tek durdurma bandı soğurucu bant durduran filtre tasarımı gerçekleştirilebilmektedir. Bu filtre türünde direncin konumuna bağlı olarak sadece birinci veya sadece ikinci durdurma bandı soğurucu olan bant durduran filtre tasarlanabilir. Giriş portuna yakın saplamaya ve ortadaki açık devre saplamaya direnç eklenmesiyle iki durdurma bandı da soğurucu olan çift bantlı bant durduran filtre cevabı elde edilmektedir. Sadece birinci durdurma bandının, sadece ikinci durdurma bandının ve her iki durdurma bandının birden soğurucu olarak elde edildiği üç filtre imal edilmiş ve ölçümleri gerçekleştirilmiştir. Durdurma bantlarının merkez frekansları 1.18 GHz ve 3.5 GHz’de ölçülmüştür. Ölçüm sonuçları simülasyonlarla oldukça uyumlu bir şekilde elde edilmiştir.

Anahtar Kelimeler

• Soğurucu (yansımasız)
• Bant durduran
• Mikroşerit filtre

Kaynakça

1. [1] Gorur A, Karpuz C. "Uniplanar compact wideband bandstop filter". IEEE Microwave and Wireless Components Letters, 13(3), 114-116, 2003.
2. [2] Hong JS. "Microstrip dual-mode band reject filter". IEEE MTT-S International Microwave Symposium Digest, 2005, Long Beach, CA, USA, 17 June 2005.
3. [3] Gorur A. "Bandstop filter with a wider upper passband using microstrip open-loop resonator". APMC 2001. 2001 Asia-Pacific Microwave Conference (Cat. No.01TH8577), Taipei, Taiwan, 03-06 December 2001.
4. [4] Eryilmaz GM, Gunturkun E, Gorur A, Karpuz C. "Microstrip bandstop filter using a dual-mode square loop resonator". Microwave and Optical Technology Letters, 51, 147-150, 2009.
5. [5] Gorur A, Gunturkun E, Karpuz C, "Dual-mode microstrip bandstop filters using square loop resonators". 2014 44th European Microwave Conference, Rome, Italy, 06-09 October 2014.
6. [6] Jachowski DR. “Passive enhancement of resonator Q in microwave notch filters”. 2004 IEEE MTT-S International Microwave Symposium Digest, Fort Worth, TX, USA, 06-11 June 2004.
7. [7] Morgan MA, Boyd TA. "Theoretical and experimental study of a new class of reflectionless filter". IEEE Transactions on Microwave Theory and Techniques, 59(5), 1214-1221, 2011.
8. [8] Lee J, Lee TC, Chappell WJ. "Lumped-Element realization of absorptive bandstop filter with anomalously high spectral ısolation". IEEE Transactions on Microwave Theory and Techniques, 60(8), 2424-2430, 2012.

9. [9] Chieh JCS, Rowland J. "Quasi-Lumped element bridged-T absorptive bandstop filter". IEEE Microwave and Wireless Components Letters, 26(4), 264-266, 2016.
10. [10] Liu G, Xu J, Liu Z. "A narrowband absorptive band-stop filter based on a resistor-loaded compact resonator". 2017 Progress in Electromagnetics Research Symposium-Spring (PIERS), St. Petersburg, Russia, 22-25 May 2017.
11. [11] Lee J, Kim B, Lee K, Chappell WJ. "Bandwidth-enhanced lumped-element absorptive bandstop filter topology and its application to LTCC bandstop filter design". International Journal of Microwave and Wireless Technologies 7(6), 691-698, 2015.
12. [12] Yang CH, Wu CH, Tang CW. "Design of a wideband microstrip bidirectional absorptive bandstop filter". 2019 IEEE Asia-Pacific Microwave Conference (APMC). IEEE, Singapore, 10-13 December 2019.
13. [13] Chen Z, Li K, Qu D, Zhong X, Sun L, Ma W. "A novel microstrip absorptive bandstop filter". 2017 IEEE 2nd Advanced Information Technology, Electronic and Automation Control Conference (IAEAC), Chongqing, China, 25-26 March 2017.
14. [14] Chien SH, Lin YS. "Novel wideband absorptive bandstop filters with good selectivity". IEEE Access, 5, 18847-18861, 2017.
15. [15] Liu C, Li M, Zhu Q. "Lumped-element absorptive bandstop filter based on dual composite right/left handed transmission line". 2017 Sixth Asia-Pacific Conference on Antennas and Propagation (APCAP), Xi'an, China, 16-19 October 2017.
16. [16] Karpuz C, Görür A, Güntürkün E, Görür AK. "Asymmetric response dual-mode dual-band bandstop filters having simple and understandable topology," 2009 Asia Pacific Microwave Conference, Singapore, 07-10 December 2009.
17. [17] Karpuz C, Eryilmaz GM, Gorur A. "Dual-mode dual-band microstrip square loop resonators and filters". 2008 Asia-Pacific Microwave Conference, Hong Kong, China, 16-20 December 2008.
18. [18] Karpuz C, Gorur AK, Emur M. "Quad-Band microstrip bandstop filter design using dual-mode open loop resonators having thin film capacitors". IEEE Microwave and Wireless Components Letters, 26(11), 873-875, 2016.
19. [19] Gorur AK, Basmaci FAN, Dogan E, Karpuz C, Gorur A. "Dual-Mode dual-band microstrip bandstop filter design with independently tunable center frequencies". Microwave and Optical Technology Letters, 59(10), 2542-2547, 2017.
20. [20] Chang EW, Lin YS. "Miniature multi-band absorptive bandstop filter designs using bridged-T coils". IEEE Access, 6, 73637-73646, 2018.
21. [21] Chaudhary G, Qi W, Lim J, Jeong Y. "Arbitrary terminated negative group delay circuit with constant signal attenuation and its application to absorptive bandstop filter". 2019 49th European Microwave Conference (EuMC), Paris, France, 01-03 October 2019.
22. [22] Chen Z, He L, Qu D, Zhong X, Li K. "Design of absorptive bandstop waveguide filter without lumped-element". 2017 IEEE 3rd Information Technology and Mechatronics Engineering Conference (ITOEC), Chongqing, China, 03-05 October 2017.
23. [23] Hagag MF, Abdelfattah M, Peroulis D. "Balanced octave-tunable absorptive bandstop filter". 2018 IEEE 19th Wireless and Microwave Technology Conference (WAMICON), Sand Key, FL, USA, 09-10 April 2018.
24. [24] Kong M, Wu Y, Zhuang Z, Liu Y, Kishk AA. “Compact wideband reflective/absorptive bandstop filter with multitransmission zeros". IEEE Transactions on Microwave Theory and Techniques, 67(2), 482-493. 2018.
25. [25] Cho YH, Park C, Yun SW. “4-Pole Tunable absorptive bandstop filters using folded coupled-lines with an ınductor”. IEEE Access, 10, 120191-120199, 2022.
26. [26] Sahin KO, Gorur AK, Gorur A. "Design of a compact dual-band microstrip bandstop filter with high rejection levels". 2021 13th International Conference on Electrical and Electronics Engineering (ELECO), Bursa, Turkey, 25-27 November 2021.