A.O. Afonin1, I.V. Govorun2, Al.A. Leksikov3, A.V. Ugryumov4

1-4 Kirensky Institute of Physics SB RAS (Krasnoyarsk, Russia)
2 Reshetnev Siberian State University of Science and Technology (Krasnoyarsk, Russia)
1,4 JSC «NPP «Radiosvyaz» (Krasnoyarsk, Russia)
1 nord2492@mail.ru; 2 govorun-ilya@mail.ru; 3 leksikov@iph.krasn.ru; 4 dark24@bk.ru

The article deals with the development of a compact narrowband band-stop filter. The filter consists of a dielectric substrate suspended in a metal case. The distance from the substrate to the upper screen is several times greater than to the lower one. Strip conductors forming a common line and resonators are located on one side of the substrate. The resonators are electromagnetically connected to a common line. The device's input and output ports are connected to the ends of the line. The topology of the resonator conductors forming the filter is chosen in such a way that the magnitude of the coupling due to the magnetic interaction is almost equal to the magnitude of the coupling due to the electrical interaction, but they have different signs. At a certain distance between the resonators, there is no electromagnetic coupling between them due to mutual compensation of magnetic and electrical coupling. Rectangular strip conductors are inserted between the resonators, which disrupt the compensation of electromagnetic interactions. This allows you to form a narrow bandwidth of the filter. The developed band-stop filter is made on a substrate with a relative dielectric constant εr = 80 and a substrate thickness of 0.5 mm. The internal dimensions of the enclosure are 48.8×18.0×6.3 mm3. Central frequency of the stop-band: f0 = 1483.7 MHz; attenuation at this frequency: L0 = 60.6 dB; bandwidth of the stop-band at −25 dB level: Δf = 35.9 MHz; at −50 dB level: Δf = 17 MHz. Low-frequency passband ranges from 0 to 1440 MHz, while high-frequency passband extends from 1530 MHz to 2147 MHz. The losses in these bands do not exceed 2 dB, and VSWR does not exceed 1.5.

Afonin A.O., Govorun I.V., Leksikov Al.A., Ugryumov A.V. Narrow-band band-stop filter with a suspended substrate and weakly coupled strip resonators. Achievements of modern radioelectronics. 2026. V. 80. № 3. P. 146–154. DOI: https://doi.org/10.18127/j20700784-202603-17 [in Russian]

1. Hong J.-S., Lancaster M.J. Microstrip Filters for RF. Microwave Applications. Wiley. New York. 2001.
2. Bell H.C. L-Resonator bandstop filter. IEEE Trans. MTT. 1996. № 44. Р. 2669.
3. Han X., Li C.X., Zhou Y., Zheng P.P., Cui H. Microstrip bandstop filter for preventing conduction electromagnetic information leakage of high power transmission line. Int. Journ. Ant. Prop. 2022. № 12.
4. Nizam M.M., Soh P.J., Suhaizal A.H.M. Design of a modified L-shaped bandstop filter for UWB application. IEEE MTT-S Int. Microwave & Optoelectronic Konf. (IMOK 2009). 2009. Р. 177.
5. Leksikov A.A., Afonin A.O., Aleksandrovsky A.A., Ugryumov A.V., Serzhantov A.M., Govorun I.V. Microstrip rejecting bandstop filter. 2022 IEEE International Multi-Conference on Engineering, Computer and Information Sciences (SIBIRCON). Yekaterinburg. Russian Federation. 2022. Р. 1200.
6. Lu Q., Wu X., Wang C. Compact broadband absorptive bandstop filter based on microstrip. J. Phys. Сonf. Ser. 2020. V. 1651. P. 012104.
7. Belyaev B.A., Leksikov A.A., Trusov Yu.N., Tyurnev V.V., Shepov V.N., Shihov Yu.G. Miniatyurizirovannye mikropoloskovye SVCh-fil'try. Preprint №730F. Institut fiziki SSSO AN RF. Krasnoyarsk. 1993. № 63 (In Russian).
8. Wu C.-H., Tang C.C., Tang C.W. Design of the microstrip bandstop filter with high insertion loss. IEEE Transactions on Components, Packaging and Manufacturing Technology. 2018. № 9. Р. 122.
9. Tyurnev V.V. Coupling coefficients of resonators in microwave filter theory. PIER B. 2010. V. 21. № 47.
10. Belyaev B.A., Laletin N.V., Leksikov A.A. Coupling coefficients of irregular microstrip resonators and frequency-selective properties of two-section irregular microstrip filter. Journ. of Comm. Thech. and Electron. 2002. V. 14, № 47 (1).
11. Belyaev B.А., Govorun I.V., Leksikov А.А, Serzhantov А.М., Leksikov Аn.А. Reflective power limiter for X-band with HTSC Switching element. IEEE Transactions on applied superconductivity. 2016. № 26. Р. 7407639.
12. Govorun I.V., Leksikov А.А. New method for observation ferromagnetic resonance spectra. Actual Problems of Electronics Instrument Engineering (APEIE). 2018 14th International Scientific-Technical Conference. 2018. № 4. Р. 41.