一种高滚降宽阻带低通微带滤波器

普通的阶梯阻抗低通滤波器滚降系数一般低于80 dB/GHz,阻带抑制小于20 dB,使其应用受到较大限制;文中首先从理论上分析并设计了具有宽阻带优势的阶梯阻抗滤波器,然后引入扇形短截线结构提高滚降系数,设计了一款通带为0~6 GHz的高滚降宽阻带的微带低通滤波器。利用ADS和HFSS分别对滤波器进行了建模、仿真和优化;最后采用RO4003板材加工并对实物进行了测试。测试结果显示,所设计的滤波器3 dB截止频率为6.02 GHz,滚降系数为123 dB/GHz,阻带6.24~20 GHz,阻带抑制大于30 dB。

Wide Stopband Microstrip Low-Pass Filter with Sharp Roll-Off

Commonly, the roll-off factor of the stepped impedance low-pass filters is lower than 80 dB/ GHz and the stopband suppression is less than 20 dB, which limits its application. First, in this paper, a stepped impedance filter with wide stopband is analyzed and designed. Then, by introducing the fan-shaped stub to improve roll-off coefficient, a sharp roll-off and wide stopband microstrip low-pass filter with passband of 0-6GHz is designed. The filter is modeled, simulated, and optimized by using ADS and HFSS. Finally, the filter is fabricated on RO4003 plate and it is tested for verification. The measured results show that the 3 dB cut-off frequency is 6.02 GHz, the roll-off factor is 123 dB/GHz, the stopband is from 6.24 to 20 GHz, and the stopband suppression is greater than 30 dB.