基于CSRR的小型化低通滤波器的研究

Miniaturization of Low-pass Filter Based on CSRR

提出了一种采用互耦环缝谐振器(CSRR)结构实现小型化低通滤波器的方法,根据等效电路研究了环缝的半径、开口间距和径向间距对低通滤波器性能的影响。研究表明,增大环缝半径和减小开口间距可降低截止频率,增大径向间距可提高带外抑制能力,这样在不增大滤波器体积的基础上降低了滤波器的截止频率,从而实现低通滤波器的小型化。

A method using the complementary split ring resonators (CSRR) to miniaturize low-pass filters is presented in this paper. According to the equivalent circuits, the impacts of the radius, width of the open gap and width of the gap between the outer and inner rings are investigated. It is found that increasing the radius of the ring and decreasing the width of the open gap lowers the cut-off frequency, and that widening the gap between the outer and inner rings results in better suppression of the band. The cut-off frequency of the low-pass filter is, thereby, decreased without enlarging its size, and the miniaturization of the low-pass filter is realized.