A novel capacitive loaded U-slot defected ground structure (DGS) is presented in this letter to provide narrowband rejection property. The principles for the selective rejection and the strategies for size-reduction and external Q-factor improvement are detailed based on transmission line equivalent model and the lumped parallel RLC model developed from transmission line model at resonance frequency. The design concept is well validated by the design and measurement of an exemplary high Q BSF.
"Capacitive Loaded U-Slot Defected Ground Structure for Bandstop Filter with Improvement q
Factor," Progress In Electromagnetics Research Letters,
Vol. 65, 31-36, 2017. doi:10.2528/PIERL16111002
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