Increasing Quality Factor of Two-Stub Resonator
DOI:
https://doi.org/10.20535/RADAP.2023.94.58-63Keywords:
resonator, transmission line, open-circuited stub, short-circuited stubAbstract
Introduction. Narrowband filters and oscillators based on resonators are used in radiolocation, wireless and mobile communications, testing and measuring equipment. Coupled resonators form a bandpass characteristic. Resonance structures based on transmission line stubs are widely used, in particular, a two-stub resonator with open-circuited stubs. The advantages of such a resonator are a high steepness of the transmission response and the presence of zeros near the passband. The purpose of this paper is to increase two-stub resonator quality factor by replacing conventional open-circuited one-section stubs with two-section ones.
1 Conditions for comparing the characteristics of stubs. The frequency dependence of the resonator's reactive conductivity determines both the quality factor and the level in the resonator's suppression bands. It is shown that at a given level in the suppression bands, one-section and two-section stubs should have the same low-frequency capacities.
2 Comparison of reactive characteristics of open-circuited two-section and one-section stubs. The frequency dependences of reactive conductivity of open-circuited two-section and one-section stubs are given. The steepness of the reactive conductivity of the two-section stub is higher, which makes it possible to increase the quality factor of the two-stub resonator. Rise in steepness increases with the decrease in the length of the two-section stub and reaches 23%. The two-section stub is shorter than the one-section stub.
3 Resonator based on open-circuited two-section stubs. The transmission response of a two-stub resonator with open-circuited two-section stubs is presented. The resonator has a 15% higher quality factor and half the length compared to a resonator with one-section stubs.
4 Resonator based on open- and short-circuited stubs. The transmission response of a two-stub resonator with open-circuited two-section and short-circuited one-section stubs is given. In such a resonator, there are no parasitic responses at zero and doubled frequencies. The disadvantages are the short length of the short-circuited stub (which complicates its constructive implementation), the worse steepness of frequency response on the side of lower frequencies and only one zero.
5 Results discussion. A two-stub resonator with one-section stubs is half-wave. The length of the two-stub resonator with two-section stubs is much shorter. The quality factor of this resonator increases with decreasing length, since the steepness of its reactive conductivity increases with decreasing stub length. The limitations are the minimum acceptable length of the stub section and the maximum acceptable difference in the characteristic impedances of the sections, which increases as the length decreases.
Conclusion. The frequency dependence of the reactive conductance of an open two-section stub has a steeper slope compared to an open one-section stub. Increase in steepness reaches 23%.
Given the frequency response parameters, the considered resonator with open-circuited two-section stubs has a 15% higher quality factor and half the length. Making one of the resonator stubs short-circuited allows you to expand the suppression bands.
The development of the research is the consideration of the formation of the bandpass characteristic by the proposed resonators.
References
References
Hong J.-S. (2011). Microstrip Filters for RF/Microwave Applications, 2nd ed. N. Y., Wiley, 656 p.
Joines W. T., Palmer W. D. and Bernhard G. T. (2013). Microwave Transmission Line Circuits. Norwood, MA, Artech House, 320 p.
Makimoto M. and Yamashita S. (2001). Microwave Resonators and Filters for Wireless Communication: Theory, Design and Application. Berlin, Heidelberg, Springer-Verlag, 162 p. DOI: 10.1007/978-3-662-04325-7.
Feng W., Ma X., Shi Y., Shi S. and Che W. (2020). High-Selectivity Narrow- and Wide-band Input-Reflectionless Bandpass Filters with Intercoupled Dual-Behavior Resonators. IEEE Transactions on Plasma Science, Vol. 48, Iss. 2, pp. 446–454. DOI: 10.1109/TPS.2020.2968481.
Yang Z., Cheng J., Wang J., Shang H., and Gao Q. (2021). A DBR Microstrip Duplexer Based on Improved Microstrip Cross-Shaped Resonators. 2nd China International SAR Symposium (CISS), pp. 1–8. DOI: 10.23919/CISS51089.2021.9652311.
Wu Z., Shi G., Lu X., Liang R., Wen X., Wang J., et al. (2021). A W-band air-filled coaxial bandpass filter employing micro metal additive manufacturing technology. Int. J. RF Microw. Comput.-Aided Eng., Vol. 31, Iss. 1, e22768. DOI:10.1002/mmce.22768.
Allanic R., Berre D. Le, Quendo C., Chouteau D., Grimal V., Valente D. and Billoué J. (2021). Switchable DBR Filters Using Semiconductor Distributed Doped Areas (ScDDAs). Electronics, Vol. 9, Iss. 12, 2021. DOI: 10.3390/electronics9122021.
Raguénès C., Fourn E., Quendo C., Allanic R. and Le Berre D. (2022). Application of chalcogenide glass to DBR filter reconfiguration. Journées Nationales Microondes, Limoges, France, hal-03986677.
Johnson L., Bouazzaoui H., Meyer E., Meyer P., Potelon B., Quendo C. and Allanic R. (2022). Novel High-Q Partially Air-Filled Pedestal Resonator and Filter Integrated in a Printed Circuit Board (PCB). IEEE Access, Vol. 10, pp. 10160–101167. DOI: 10.1109/ACCESS.2022.3208351.
Nisamol T. A., Abdulla P. and Rekha T. K. (2022). Modified Inverted Microstrip Integrated Filter. 2022 11th International Conference on Modern Circuits and Systems Technologies (MOCAST), pp. 1–4. DOI: 10.1109/MOCAST54814.2022.9837743.
Wu W.-J. and Zhao W.-S. (2022). A Quality Factor Enhanced Microwave Sensor Based on Modified Split-Ring Resonator for Microfluidic Applications. IEEE Sensors Journal, Vol. 22, Iss. 23, pp. 22582–22590. DOI: 10.1109/JSEN.2022.3215149.
Manzoor Z., Sinanis M. D., Mkhitaryan V., Yesilyurt O., Kildishev A. V. and Peroulis D. (2022). A Miniaturized X-band High-Index Supercavity Resonator in Microstrip Technology. 2022 52nd European Microwave Conference (EuMC), pp. 568–571. DOI: 10.23919/EuMC54642.2022.9924352.
Downloads
Published
How to Cite
Issue
Section
License
Copyright (c) 2023 Юрій Васильович Непочатих
This work is licensed under a Creative Commons Attribution 4.0 International License.
Authors who publish with this journal agree to the following terms:
- Authors retain copyright and grant the journal right of first publication with the work simultaneously licensed under a Creative Commons Attribution License that allows others to share the work with an acknowledgement of the work's authorship and initial publication in this journal.
- Authors are able to enter into separate, additional contractual arrangements for the non-exclusive distribution of the journal's published version of the work (e.g., post it to an institutional repository or publish it in a book), with an acknowledgement of its initial publication in this journal.
- Authors are permitted and encouraged to post their work online (e.g., in institutional repositories or on their website) prior to and during the submission process, as it can lead to productive exchanges, as well as earlier and greater citation of published work (See The Effect of Open Access).
