Dual-band Bandpass Filter for S-band
ZHAO Yinyuan
ZHANG Binzhen
DUAN Junping
WANG Jiayun
Abstract：The BPF proposed in this article consists of a cross finger coupling structure and five E-type resonator units.The equivalent circuit model of this structure is constructed and analyzed by using odd and even mode theory.By adjusting the length of the E-type resonator branches,the center frequency of the two differential mode(DM)passbands can be controlled.The cross fin-ger coupling structure achieves the required external coupling between two frequency bands and adds out of band suppression.Ac-cording to the measurement results,relative bandwidths of 38.5%and 10.63%are obtained at 2.7 GHz and 4 GHz frequencies,re-spectively,and the DM return loss of both bands is greater than 15.6 dB.
Keywords：dual-band BPFodd even mode theoryE-type resonatorinterdigital coupling
Publication Date：2025-02-20
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：4( 74-77 )