Spoof Surface Plasmon Polaritons with Defected Ground Structure for Bandstop Filter

In this paper, a bandstop filter based on spoof surface plasmon polaritons with defected ground structure (DGS) is proposed, which can be realized waveguide based on stripline circuits. By adjusting the geometric structure of the U-slot of the DGS, the operating stopband frequency of the filter can be flexibly adjusted. The effect of the bandstop filter is verified through the S parameter and electric field distribution diagram. The stopband width can reach about 2 GHz with good suppression characteristics. The influence of the key parameters of the defected ground structure on the bandstop performance is analyzed, which has guiding significance for the subsequent improvement and optimization.