一种准光带阻滤波器的仿真与实验研究

Simulation and Experiment Study of Quasi-optical Band-stop Filter

对中心频率为225GHz的谐振环结构(SRR)带阻滤波器进行了仿真分析和实验研究。采用HFSS仿真模拟技术,研究了SRR开口宽度、线宽、加载介质以及极化角度等相关参量对其谐振特性的影响。结果表明,该带阻滤波器的频率响应特性对场极化角度的敏感性很低,具有较好的稳定性;实验中测试到样品的中心频率为225.6GHz,与仿真结果有一定的偏差。通过进一步分析发现,影响频率偏移的主要因素是样品的实际尺寸偏小和介质的介电常数偏大,导致实际测试响应频率小于设计值。

A band-stop filter based on split ring resonances （SRR） was studied. The influences of related parameters and incidence wave polarization of split ring resonances on frequency response characteristics were investigated by using HFSS code. The simulation results show that the frequency response characteristics of split ring resonances have little changed with the incidence wave polarization direction. Band stop filter based on split ring resonances is fabricated and tested. The center resonant frequency of 2-95.6GHz for this filter is observed in experiment. The result in experiment deviates about 6.4GHz comparing to design value 232GHz. There are two reasons. First, the actual size of sample is smaller than that of the design. Second, the dielectric constant of the substrate is larger than that used in simulation.