多口三环CSRR微带低通滤波器的研究与设计

提出一种新型的多口三环CSRR结构,利用CSRR谐振器的单极点低通特性和环与微带线之间的耦合,构成低通滤波器.分析该结构的等效电路模式,指出谐振频率的计算公式.使用HFSS适当优化参数,可以得到性能良好的低通滤波器.其-3 dB截止频率8.76 GHz,通带内插入损耗小于0.3306 dB,通带内回波损耗小于-13.810 2 dB,衰减15 dB以上阻带带宽达到10.31 GHz.为了改善通带内的回波损耗,在微带线两侧加载并联开路枝节.其-3 dB截止频率8.385 GHz,通带内插入损耗小于0.174 7 dB,通带内回波损耗小于-19.707 7 dB,衰减15 dB以上阻带带宽达到10.7 GHz.

Research and Design of Microstrip Low-Pass Filter based on Multi-Slit Tricyclic CSRR

A novel multi-slit tricyclic Complementary Split Ring Resonator (CSRR) is proposed in this paper. By using single-pole low-pass characteristic of CSRR and the coupling between the ring and the microstrip line can constitute the microstrip low-pass filter (LPF). Analysis of the equivalent circuit model of the structure and the calculation formula of resonant frequency is pointed out. Appropriate optimization parameters by using HFSS can get a good performance of the low-pass filter. Its -3dB cut-off frequency is 8.76GHz, the insertion loss is less than 0.3306dB and the reflection loss is less than -13.8102dB in the pass-band. The stop-band width with 15dB attenuation can be up to 10GHz. In order to improve the return loss in the pass-band, the shunt branch was added on both sides of the microstrip line. Its -3dB cut-off frequency is 8.385GHz, the insertion loss is less than 0.1747dB and the reflection loss is less than -19.7077dB in the pass-band. The stop-band width with 15dB attenuation can reach 10.7GHz.