On-chip bandpass filters based on spoof surface plasmon polaritons

In the article, a miniaturized on-chip bandpass filter based on SSPPs (spoof surface plasmon polaritons) with SIW (substrate integrated waveguide) is designed. is designed. The bandpass filters mentioned in this paper utilizes the characterization of low-frequency pass-through of SSPPs to generate a high-frequency cutoff, and the high-pass characteristic generated by the capacitive effect between the two partial metal lands on the back to generate a low-frequency cutoff, combining the two to form a bandpass effect. Results of the simulation show that the filter has an insertion loss of less than -2dB in the 61GHz-95GHz band, while the out-of-band isolation is greater than 20dB.The bandpass filter has the benefits of transmission loss, wide bandwidths, and compact structure. In addition, the low-frequency cutoff is simpler in terms of process as the solution of not connecting the metal ground at the back does not require a perforation operation.