三陷波微带超宽带滤波器设计

Design of triple notch microstrip ultra-wideband filter

旨在解决超宽带滤波器存在的尺寸偏大、陷波个数不足的问题,采用改进的多模谐振器以及新型缺陷接地结构,提出了一种具有三陷波和较好选择性的微带超宽带滤波器。设计谐振器在阶梯阻抗谐振器两侧和下方加载枝节,构建了超宽带滤波器的通带和两个陷波,并设计缺陷地面结构,在增加陷波的同时对陷波特性加以改善。经仿真显示,该滤波器通带带宽为2.8~10.6 GHz,在3.8,5.9,8.2 GHz处形成了三个陷波,且三个陷波深度均达到了-20 dB。对于几种窄带信号有着较好的抑制,适用于电路的集成。

The purpose of this paper is to solve the problem of large size and insufficient number of the notch in ultra-wideband filters.An improved multimode resonator and a new defect grounding structure were adopted and a microstrip ultra-wideband filter with three notches and better selectivity was proposed.The resonator was loaded with dendrites on both sides and below the stepped-impedance resonator,and the passband and two notches of the ultra-wideband filter was formed.The defective ground structure was designed to improve the notch characteristics while increasing the notch.The simulation results indicate that the filter has a passband from 2.8 GHz to 10.6 GHz,with three notches at 3.8 GHz,5.9 GHz and 8.2 GHz.And the depths of all three notches reaches-20 dB.It has good rejection for several narrowband signals,which is suitable for the circuit integration.