Spoof surface plasmon-based bandpass filter with extremely wide upper stopband
Liu Xiaoyong1, 2, Zhu Lei2, †, 
, Feng Yijun1, ‡,
, Feng Yijun1, ‡, (a) Schematic diagram of the symmetric spoof SPPs structure with input and output microstrip line sections. (b) Schematic diagram of a shunt stepped-impedance resonator. (c) Calculated dispersion curve. (d) Simulated results of a spoof-SPPs based lowpass filter and the bandpass filter with stepped-impedance resonators added.
