基于互补开口环谐振器的超宽带低通滤波器

Novel Compact Ultra Wideband Low-pass Filters Using Complementary Split Ring Resonators(CSRRs)

为有效抑制寄生通带和高次谐波的影响,采用互补开口环谐振器结构设计了三种紧凑的新型超宽带低通滤波器。研究了互补开口环谐振器级联的阻带特性,并用来改善滤波器的通带、阻带性能。通过对比第一种滤波器的仿真结果,表明加载互补开口环谐振器的低通滤波器具有更好的裙边衰减和更优的阻带特性。在此基础上,还设计了另外两种新型的超宽带低通滤波器,并对三种滤波器进行了加工和测量,实测结果与仿真结果均较吻合。相关结果表明,三种滤波器具有紧凑的结构、超宽的通带,并在较宽阻带内具有良好的衰减性能。

In order to suppress the spurious passbands and harmonics which appear at high frequencies, three compact ultra wideband （UWB） low-pass filters （LPFs） using the complementary split ring resonators （CSRRs） are proposed in this paper. The stopband characteristics of the microstrip lines with cascaded CSRRs are studied firstly. Then the uses of CSRRs to improve the passband and stopband performances of LPFs are studied. Compared the frequency response characteristics of the first type of LPF with and without CSRRs, the filter with CSRRs has better attenuation skirt and better stopband characteristics. Then other two types of UWB LPFs are designed respectively. Three types of LPFs are fabricated and measured. The measured results are in good agreement with the simulated ones, which shows that three LPFs with CSRRs all have compact dimensions, ultra wideband passbands and excellent attenuation characteristics in the wide stopband.