一种新型SRR缺陷地面结构低通滤波器

A Novel SRR Defected Ground Structure for Lowpass Filter

该文提出一种新型开口谐振环(Split-Ring Resonator,SRR)缺陷地面结构(Defected Ground Structure,DGS)。这种结构与传统哑铃形DGS结构相比,具有陡峭的带隙和平坦的低通特性。文中详细分析了开口谐振环DGS单元的等效电路以及结构参数与电参数之间的关系。在此基础上提出一种加载开路枝节的SRR DGS单元模型以提高带外抑制,采用这种单元的级联周期结构设计并制作了一种紧凑的S波段低通滤波器。测试结果表明,该滤波器带内插损小于0.5dB,带外抑制度在30 dB以上。

A novel Split-Ring Resonator （SRR） Defected Ground Structure （DGS） is presented. Compared with the conventional dumbbell DGS, this structure has a sharp band-gap and flat low-pass characteristic. A detailed analysis of the equivalent circuit of the cell model and the relationship between physical sizes and electrical parameters is made. Then an improved SRR DGS cell model loaded with open stubs is proposed in order to improve the out-band suppression. Based on this structure, a compact S-band microstrip lowpass filter is designed and fabricated. The measured results show that, this filter has a low insertion loss of below 0.5dB and a high out-band suppression of more than 30dB.