Investigation of Band-Pass Filters of K-Range on Rectangular Concentric Resonators

Introduction. Simple-shaped cavity resonators: rectangular, cylindrical and coaxial, are widely applied in modern microwave engineering in design of different functional devices of middle and high power levels. Parameters of resonators can be obtained analytically by using expressions from literature. Concentric resonators, performed on the basis of classical simple-shaped cavities with a central metallic core represent a new class of electrodynamic systems of microwave range, the properties of which remain poorly studied. One of these structures, named a rectangular concentric resonator (RCR) is proposed in the paper as a basic unit of K-band bandpass filters (18...26 GHz).

Aim. To study potential possibilities of RCR for creation electromagnetic signals filtration devices of micro wave range.

Materials and methods. The finite element method implemented in the package COMSOL was used to investigate electrodynamic characteristics of RCR and scattering matrix parameters of the microwave filters on RCR basis.

Results. Simple polynomial expressions for computation of normalized resonant wavelengths of RCR were obtained at the first stage of modeling. Next, two models of passband microwave filters by RCR with different sizes were built and their EM characteristics were studied. Cavities sizes were determined numerically and practical recommendations on the realization of a new type bandpass microwave filters were formulated.

Conclusion. New results of the finite-element analysis of spectral characteristics of two models of bandpass Krange filters on rectangular concentric resonators were represented. The advantages of the filters were indicated. Simple analytical expressions for calculation of the resonance wavelengths of the considered concentric resonators were obtained.

1. SVCh-fil'try i mul'tipleksory dlya sistem kosmicheskoi svyazi [Microwave Filters and Multiplexers for Space Communications Systems], ed. by V. P. Meshchanov. Moscow, Radiotekhnika, 2017, 256 p. (In Russ.)

2. Cameron R. J., Kudsia C. M., Mansour R. R. Microwave Filters for Communication Systems. New York, Wiley, 2007, 772 p.

3. Broun T. M. Satellite Communication Payload and System. Boston, Wiley-IEEE, 2012, 400 p.

4. Doumanis E., Goussetis G., Kosmopoulos S. Filter Design for Satellite Communications. Boston, Artech House, 2015, 203 p.

5. Shang X., Li J., Guo C., Lancaster M. J., Xu J. 3D Printed Filter based on Helical Resonators with Variable Width. Proc. of the IEEE MTT-S Intern. Symp. Honolulu, USA, 2017, pp. 1587–1590. doi: 10.1109/MWSYM.2017.8058936

6. San-Blas A., Vidal A., Muller A. A., Soto P., Mira F., Perez-Soler F. J., Gimeno B., Boria V. E. Flexible and Efficient Computer-Aided Design Tool for Advanced CombLine Rectangular Waveguide Filters. Intern. J. of RF and Microwave Computer-Aided Engineering. 2015, vol. 25, no. 8, pp. 696–708. doi: 10.1002/mmce.20908

7. Ossorio J., Melgarejo J. C., Boria V. E., Guglielmi M., Bandler J. W. On the Alingment of Low-Fidelity and HighFidelity Simulation Spaces for the Design of Microwave Waveguide Filters. IEEE Trans. on Microwave Theory and Techniques. 2018, vol. 66, no. 12, pp. 5183–5196. doi: 10.1109/TMTT.2018.2871022

8. Mira F., San Blas A. A., Boria V. E., Rogla L. J., Gimeno B. Wideband Generalized Admittance Matrix Representation for the Analysis and Design of Waveguide Filters with Coaxial Excitation. Radio Science. 2013, vol. 48, no. 1, pp. 50–60. doi: 10.1002/rds.20013

9. Bastioli S., Snyder R. V., Macchiarella G. Design of InLine Filters with Strongly Coupled Resonator Triplet. IEEE Trans. on Microwave Theory and Techniques. 2018, vol. 66, no. 12,pp. 5585–5592. doi: 10.1109/TMTT.2018.2867004

10. Bastioli S., Marcaccioli L., Sorrentino R. Compact Dual-Mode Rectangular Waveguide Filters using Square Ridge Resonators. Intern. J. of Microwave and Wireless Technologies. 2009, vol. 1, no. 4, pp. 241–247. doi: 10.1017 /S1759078709990286

11. Fahmi M. M., Ruiz-Cruz J. A., Mansour R. R., Zaki K. A. Compact Ridge Waveguide Filters with Arbitrary Placed Transmission Zeros using Nonresonanting Nodes. IEEE Trans. on Microwave Theory and Techniques. 2009, vol. 57, no. 12, pp. 3354–3361. doi: 10.1109/TMTT.2009.2034423

12. Davidovich M. V. Iteratsionnye metody resheniya zadach elektrodinamiki [Iterative methods for solving electrodynamics problems]. Saratov, Izd-vo Sarat. un-ta, 2014, 240 p. (In Russ.)

13. Komarov V. V., Bushanskiy S. K. Microwave Filters on Concentric Cavity Resonators. Radioengineering, 2018, no. 8, pp. 140–143. doi: 10.18127/j00338486-201808-26 (In Russ.)

14. Wu Y.-M., Zhou S.-Y., Lin J.-Y., Zhou L. W., Wong S.-W., Zhu L., Chu Q.-X. Design of Wideband Bandpass Filter using Quadruple-Mode Rectangular Cavity Resonator. Proc. of the IEEE Asia-Pacific Conference on Antennas and Propagation. 2017, Xian, China, 16–19 Oct., 2017, pp. 1–3. doi: 10.1109/APCAP.2017.8420607

15. Komarov V. V., Bushanskiy S. K. The Quality Factor of Concentric Resonators. Radioengineering, 2019, no. 7, pp. 32–37. doi: 10.18127/j00338486-201907(10)-06

16. Sharov G. A. Volnovodnye ustroistva santimetrovykh i millimetrovykh voln [Waveguide Devices of Centimeter and Millimeter Waves]. Moscow, Goryachaya Liniya – Telekom, 2016, 640 p. (In Russ.)