太赫兹mesh带通滤波器的设计与仿真

基于太赫兹波的大气吸收窗口，设计了一款四级级联的太赫兹mesh带通滤波器。此滤波器的中心频率为0.25 THz，在3 dB处带宽为0.1 THz，在通带内的插入损耗为1.5 dB，纹波系数小于0.5 dB，在室温下通带内的透过率能达80%以上，且此滤波器的中心工作频率和带宽可以通过缩放mesh槽孔的尺寸来调节。利用电磁仿真软件HFSS，结合周期边界条件及理想匹配层吸收边界条件模拟了太赫兹mesh带通滤波器的mesh排列方式、介质衬底及不同入射角度的入射波、不同极化方式等因素对滤波器透过率、插入损耗的影响。

Design and simulation of terahertz mesh bandpass filter

A fourstage cascade terahertz mesh bandpass filter has been designed according to the atmospheric absorption windows of terahertz waves. The center frequency of the filter is 0.25 THz, the bandwidth is 0.1 THz at 3 dB, the transmittance is greater than 80%, the ripple factor is less than 0.5 dB in the passband, and both of the center frequency and the bandwidth can be adjusted by scaling the size of mesh slot. The HFSS simulation conducted under periodic boundary conditions and absorbing boundary condition of perfectly matched layers shows the transmittance and insertion loss of this filter with different mesh arrangements anddielectric substrates, under incident waves of different incidence angles and different polarizations.