Miniaturized spoof SPPs filter based on multiple resonators or 5G applications

Abstract

This paper presents a novel and compact band-pass filter based on spoof surface plasmon polaritons (SSPPs) concept for 5G applications. In the first place, an SSPPs unit cell including L-shaped grooves and its equivalent circuit model are introduced. The obtained results from dispersion analysis shows that cut-off frequency of the cell can be considerably decreased thanks to its geometrical configuration. In the second place, a miniaturized SSPP transmission line (TL) consisting of the proposed unit cell with cut-off frequency of 29.5 GHz is designed. Two mode convertors have been employed for efficient connection between coplanar waveguides and SSPP TL. Moreover, a new method based on loading one unit cell of SSPP TL by stub resonators is proposed in order to block a specific frequency band. An equivalent circuit model for the cell with the resonators is proposed to predict rejected frequency range. Thereafter, as an example of our method, a SSPPs filter operating at 26.5–29.5 GHZ is designed by means of connecting stub resonators with different lengths to provide close resonance frequencies. The circuit model, full wave simulation, and measurement results are in a good agreement. The results of proposed groundless SSPP TL and filter structures are promising to make groundless 5G applications possible.

Compact Broadband Low-pass Filter with Novel Fishbone Structure Based on Spoof Surface Plasmon Polariton

“…Table 2 shows a comparison of the proposed SSPP filter and several other SSPP filters described in different references. Compared with the filters presented [40][41][42][43][44][45], the proposed compact SSPP lowpass filter has better performance in terms of size.…”

Independently controllable dual band filtering characteristics of a spoof surface plasmonic waveguide employing compound slot structure

“…Until 2004, Pendry et al proposed designed SPPs for working at microwave or terahertz bands by the periodically structured surface [12]. Since then, various surface plamonic filters have been reported thanks for the flexible dispersion engineering by shaping the artificial grooves or holes in metals [13][14][15][16][17][18][19][20][21][22][23]. For example, Xu et al proposed a simple low-pass plasmonic filter, whose cut-off frequency can be tailored by the depth of the groove [16].…”

“…In addition, how to realize the miniaturization of spoof surface plasmon polaritons (SSPPs) devices has attracted a lot of attention, which is necessary for large-scale advanced microwave and terahertz integrated devices. T-shaped, fishbone-shaped and other various kinds of corrugated groove structure were proposed in order to further miniaturize physical size of plasmonic filters [17][18][19][20][21][22][23]. A novel band-pass filter based on SSPPs composed of SSPPs unit structure with L-shaped grooves was proposed, which can greatly reduce the size of SSPPs structure [23].…”

“…T-shaped, fishbone-shaped and other various kinds of corrugated groove structure were proposed in order to further miniaturize physical size of plasmonic filters [17][18][19][20][21][22][23]. A novel band-pass filter based on SSPPs composed of SSPPs unit structure with L-shaped grooves was proposed, which can greatly reduce the size of SSPPs structure [23].…”