一种基于SIFW的小型化宽带带通滤波器

摘要

In order to realize the miniaturized RF system, this paper presents a compact and broadband bandpass filter based on folded substrate integrated waveguide (SIFW), and the simulated results are given. In order to improve the band rejection at the low passband, a cross coupling structure is introduced and two transmission zeros in the low passband are obtained. Also, a pair of CSRR slot is etched on the top and bottom microstrip to improve the characteristics in the high passband. The simulated result shows that the center frequency of the proposed filter is at 7.1 GHz, the relative bandwidth is about 47% , and the return loss and insertion loss in the passband is better than - 15 dB and 0. 7 dB, respectively.%为实现射频系统的小型化,本文设计出一种基于基片集成折叠波导( Substrate integrated folded waveguide,简称SIFW)的小型化宽带带通滤波器,并给出了仿真结果.为了改善带外抑制,滤波器通过交叉耦合,在通带低端引入两个传输零点.为改善通带高端滤波特性,在顶层和底层金属微带上刻蚀互补型开口谐振环(Complementary Split Ring Resonators,简称CSRR).仿真结果表明,所实现的滤波器中心频率在7.1 GHz,相对带宽约为47％,通带内回波损耗优于-15dB,插入损耗小于0.7dB.