Properties Studies on a Novel Spoof Surface Plasmon Polaritons Transmission Line

In this paper, a novel slow-wave transmission line based on Spoof Surface Plasmon Polaritons (SSPP) is presented with low loss. The whole structure consists of two coplanar waveguides (CPW) feeding structure, two transition parts between CPW and SPPP structure and the SSPP transmission line. The SSPP unit cell is composed of a horseshoe-shaped metal single wire. The dispersion relationship of SSPP unit cell is discussed to demonstrate the slow-wave transmission effect. The flaring metal ground and tapered horseshoe-shaped single conductor help match the impedance between CPW and SSPP transmission line. Simulated results show that the proposed transmission line has an excellent transmission property. The insertion loss is lower than 0.7dB over the frequency bandwidth of 2 - 7 GHz. Also, in this operating frequency range, the reflection coefficient is less than - 10 dB. Moreover, compared with the convention “H-shaped” SSPP transmission line, the more stable insertion loss is realized. And when this novel structure is fabricated on the Silicone media layer, the transmission characteristics can be easily changed with the stretching.