Narrow-band rejection filter based on spoof surface plasmons polariton

In this article, a narrow-band rejection plasmonic filter based on spoof surface plasmons polariton is reported. The structure is composed of a coplanar waveguide constructed with two defects at the bottom, periodic arc branches and metal strips. Varying the radian of the arc branch controls the frequency range of the filter's narrow band and the change of metal strip height enhances the rejection ability of filter. The filter is simulated and fabricated. Its simulation daters are consistent with the experimental daters. The proposed rejection filter exhibits a strong stopband in 4.8-5.0 GHz, whose transmission coefficient is less than - 35 dB in simulation. In the passband, the transmission loss is around 1 dB. It is hoped that this filter may have better application prospect in integrated circuits and microwave communication devices.