The Youth Program of National Natural Science Foundation of China (61701211)
为了解决具有陷波特性的超宽带滤波器陷波深度不够和阻带抑制能力不强等问题，设计了一款结构紧凑的双陷波超宽带滤波器，将设计的新型多模谐振器与输入、输出馈线进行耦合完成超宽带滤波器的设计，在输入馈线端加载2个开路枝节，实现了具有双陷波特性的超宽带滤波器。该滤波器通带为2.42~10.98 GHz，带内插入损耗较小，分别在5.31 GHz和8.1 GHz处产生了2个陷波，有效阻断了无线局域网(wireless local area network，WLAN)和X波段卫星通信频段窄带信号对超宽带通信系统的干扰。该滤波器不仅结构简单，并且具有很好的带外抑制能力(-66.28 dB)和足够的陷波深度(-39.71~-35.12 dB)，同时能够达到超宽带系统对滤波器插入损耗和回波损耗的要求。
In order to solve the problems of insufficient notch depth and weak stopband suppression ability of ultra-wideband filter with notch bands, a compact ultra-wideb and filter with dual notched bands is proposed in this paper. The design of the new multi-mode resonator couples with the input and output feeder to complete the design of ultra-wideband filter, and two open-circuit stubs are loaded at the input feeder, and the ultra-wideband filter with dual notched bands is realized. The pass band of the filter is 2.42~10.98 GHz, and the in-band insertion loss is small. Two notch bands are generated at 5.31 GHz and 8.1 GHz respectively, which effectively blocks the interference of narrow-band signal in wireless local area network and X-band satellite communication band to ultra-wideband communication system. The filter is not only simple in structure, but also has outstanding out-of-band suppression (-66.28 dB) and enough notch depth (-39.71~-35.12 dB). At the same time, it satisfies the requirements of ultra-wideband system for insertion loss and return loss of the filter.