Abstract
In this article, we present a rigorous design method for a symmetric reflectionless bandstop filter with coupled lines. Analytic design equations and the detailed procedure for formulating narrowband reflectionless bandstop filter structures are given in this article. The presented design theory allows us to design a symmetric reflectionless bandstop filter with a predefined transmission response and an excellent impedance matching performance over a wide frequency range. Using the circuit formulation process with the closed-form design equations presented in this article, all circuit element values and the detailed physical dimensions of a filter can be obtained in a straightforward manner. In order to verify the design equations and the filter structure, a third-order Butterworth filter example has been designed, fabricated, and measured. Overall, the return loss was measured to be larger than 10 dB over a wide frequency range from dc to 4f{0} ( f{0} : center frequency).
Original language | English |
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Article number | 9153911 |
Pages (from-to) | 4381-4389 |
Number of pages | 9 |
Journal | IEEE Transactions on Microwave Theory and Techniques |
Volume | 68 |
Issue number | 10 |
DOIs | |
Publication status | Published - 2020 Oct |
Bibliographical note
Funding Information:Manuscript received June 10, 2020; accepted June 27, 2020. Date of publication July 31, 2020; date of current version October 5, 2020. This work was supported by the National Research Foundation of Korea (NRF) through the Korea Government (MSIT) under Grant NRF-2018R1A2B6006095. (Corresponding author: Juseop Lee.) The authors are with the Department of Computer and Radio Communications Engineering, Korea University, Seoul 02841, South Korea (e-mail: juseoplee@gmail.com).
Publisher Copyright:
© 1963-2012 IEEE.
Keywords
- Absorptive filter
- reflectionless filter
ASJC Scopus subject areas
- Radiation
- Condensed Matter Physics
- Electrical and Electronic Engineering