基于齿状缺陷地的宽阻带交叉耦合SIW滤波器

Wide Stopband Cross-Coupled SIW Filter Based on Tooth-Shaped Ground Defect

提出了一种齿状缺陷地低通传输线结构,该低通传输线由多级齿状缺陷地构成,通过调节齿状缺陷地枝节长度,可以有效调节低通和阻带频率范围。利用该齿状缺陷地结构,级联交叉耦合扇形基片集成波导(SIW)滤波器,该文设计了一款高带外抑制的宽阻带滤波器,与传统SIW带通滤波器相比,其矩形系数K 40 dB=2,阻带范围大于2倍的中心频率,具有较好的通带和阻带选择特性。测试结果表明,滤波器的中心频率为10.35 GHz,3 dB和40 dB带宽分别为507 MHz和1.05 GHz,插入损耗优于1.47 dB,与仿真结果基本一致。

A low-pass transmission line structure with multi-level,tooth-shaped defects is proposed.The low-pass frequency and attenuation-band range could be effectively adjusted by varying the length of the branch of atooth-shaped defect.A wide-stopband filter with high out-of-band suppression was designed by cascading cross-coupled fan-shaped SIW filters using this tooth-shaped defect ground structure.Compared to traditional SIW bandpass filters,the rectangular coefficient,K 40 dB,had a value of two,and the stopband range was greater than twice the center frequency,demonstrating good passband and stopband selection characteristics.The test results showed that the filter s center frequency was 10.35 GHz,with 3 dB and 40 dB bandwidths of 507 MHz and 1.05 GHz,respectively.The insertion loss was better than 1.47 dB,which was consistent with the simulation results.