A plasmonic bandpass filter based on meander-slotted substrate integrated waveguide

In this paper, we propose a bandpass filter based on hybrid spoof surface plasmon polaritons (SSPPs) and substrate integrated waveguide (SIW). This filter consists of meandered slots arrays etched on the top metal layers of an SIW to support spoof surface plasmon polariton (SSPP) modes. We simulated dispersion characteristic of the unit cell, and find that we can engineer the filter's dispersion characteristics at will by tuning the parameters of the unit cell. By introducing the tapered transitions, a back-to-back microstrip to SIW to plasmon waveguide to SIW to microstrip structure is designed to realize impedance matching and momentum matching. This filter shows great filtering characteristics within a passband from 7 to 13 GHz with high return loss (> 10 dB), low insertion loss (< 3 dB), and high out-of-band rejection (> 30 dB).