新型中心开圆形槽的带通滤波器设计

The Design to Novel Bandpass Filter with Circular Slot

设计了一种新型带有两个三角形切角和中心开圆形槽的双模椭圆函数带通滤波器,并对该滤波器结构进行了仿真研究和分析。该滤波器在中心频率2.28GHz处,最小插入损耗为0.25dB,通带内在2.24~2.35GHz之间插入损耗小于1dB,在2.27~2.47GHz之间回波损耗大于20dB,3dB相对带宽为7.37%。在通带两侧2.04GHz和2.55GHz处有2个衰减极点,衰减分别是61.85dB和45.64dB,另外,在通带右侧3.28GHz处还有一个65.15dB的衰减极点。研究表明,该结构能够减小滤波器的体积,更有利于器件的小型化,同时还能够有效减小辐射损耗,使通带两侧的衰减变得更好。

A novel planar dual mode bandpass filter with two triangle corner cuts and a circular slot is designed.A simulation research and analysis to the structure of this filter have been made.The center frequency is about2.28GHz and the minimum insertion loss is0.25dB.This filter has an insertion loss<1dB within2.242.35GHz,return loss>20dB within2.272.47GHz,and the3dB fractional bandwidth is7.37%.There are two attenuation poles on both sides of the pass band.They are61.85dB and45.64dB at the frequency of2.04GHz and2.55GHz,respectively.There is also a attenuation pole on the right side of the pass band.It is65.15dB at the frequency of3.28GHz.The simulated results show that the size of designed filter is reduced,so it makes easy miniaturization.In addition,this filter can reduce radiation loss effectively,and make a better development on the attenuation on both sides of the pass band.