基于人工表面等离子体激元的多频带滤波器设计

Design of Multiband Filter Based on Spoof Surface Plasmon Polaritons

基于人工表面等离子体激元(SSPPs)设计了具有陷波功能的多频带滤波器。首先,在波导结构上引入了渐变槽形单元结构,以获得更好的色散特性,并在此基础上构建了截止频率为7.1 GHz的低通滤波器。然后,通过加载E形谐振器激发陷波,形成多频带滤波器,该谐振器有奇偶模两种谐振模式。当奇偶谐振模式同时被激发时,构成了插入损耗为3 dB、截止频率为2.83 GHz的低通滤波器和插入损耗为3 dB,带宽为2.94~4.37 GHz和4.40~7.10 GHz的两个带通滤波器。在偶模式下的谐振退化消失时,构成了插入损耗为3 dB、截止频率为2.83 GHz的低通滤波器和插入损耗为3 dB、截止频率为2.94~7.10 GHz的带通滤波器。证明了基于E型谐振器的多频带滤波器结构对SSPPs在微波领域的拓展具有重要意义。

In this paper,a multiband filter with notch function based on spoof surface plasmon polaritons(SSPPs)is designed.First,a gradualy slot unit structure is introduced into the waveguide structure to obtain better dispersion characteristics,and a low-pass filter with a cut-off frequency of 7.1 GHz is built on this basis.Then,the multiband filter is formed though exciting the stuffing wave by loading an E-shaped resonator.When the odd and even resonance modes are excited at the same time,two low-pass filters with insertion loss of 3 dB and cut-off frequency of 2.83 GHz and two band-pass filters with insertion loss of 3 dB and bandwidth of 2.94-4.37 GHz and 4.40-7.10 GHz are formed.When the resonance degradation disappears in even mode,a low-pass filter with 3 dB insertion loss and 2.83 GHz cut-pass frequency,and a band-pass filter with insertion loss of 3 dB and bandwidth of 2.94-7.10 GHz are formed.It is proved that the structure of multiband filter based on E-shaped resonator is of great significance to the development of SSPPs in microwave field in the microwave field.