基于频率选择表面的双层改进型互补结构太赫兹带通滤波器研究

通过仿真计算和实验研究了一种基于频率选择表面的双层改进型互补结构太赫兹带通滤波器.对四裂缝互补型电感电容式谐振单元结构进行了改进,可以在提高滤波性能的同时增加单晶石英介质衬底的厚度.利用电磁仿真技术设计并加工了中心频率为0.28 THz的带通滤波器,并利用太赫兹时域光谱仪测试了在0.1—0.6 THz范围内此滤波器的传输频谱特性,实验结果与仿真结果基本一致.结果表明,利用双层改进型互补结构可以设计出对于入射角度不敏感、带外抑制佳、边带陡峭度大、能有效抑制寄生谐振的宽带太赫兹带通滤波器,并降低了加工难度.

Terahertz bandpass filter using double-layer reformative complementary frequency selective surface structures

The simulation and experimental study of a bandpass frequency selective surface filter in terahertz (THz) range using double-layer modified complementary structures are conducted in this paper. The modified four-split complementary electric inductive capacitive (CELC) structure is introduced as the resonant cell of the filter. The primary design objective is to improve the filtering performances of double-layer complementary metamaterial structures built on intensified thickening quartz substrate. The bandpass filter centered at 0.28 THz is simulated, fabricated and measured. Experimental results from 0.1 to 0.6 THz measured by THz time-domain spectroscopy are in excellent agreement with simulation. The reformative CELC bandpass filter has the advantages of a low cost, low loss, steepness of skirts, out-of-band rejection, and etalon resonance rejection.
Keywords： frequency selective surfaces reformative complementary metamaterial structures terahertz bandpass filter transmission characteristics