具有陷波特性的超宽带带通滤波器设计

Design of ultra-wideband bandpass filter with notched band

提出了一种超宽带微带带通滤波器。该滤波器结构简单,仅由单级平行耦合线和两个对称的1/4波长的短路截线构成。连接至平行耦合线两端的短路截线在通带两端各产生一个衰减极点,增强了该超宽带滤波器的选择性。为了消除无线网络的干扰,在提出的滤波器结构上添加开路短截线,使该滤波器具有通带内陷波特性。利用电磁仿真软件进行优化仿真,本文设计的超宽带带通滤波器的通带范围为3.1~10.6 GHz,插入损耗小于1 d B,陷波频段为5.8~5.9 GHz,陷波深度达到–40 d B。

A microstrip bandpass filter with ultra-wideband passband was proposed. The structure of this filter is very simple. It is consist of only one parallel coupled line and two short-circuited stubs which are quarter wavelength long at the center frequency. The short-circuited stubs which are connected at the input/output ends of the parallel-coupled lines obtain one pair of transmission zeros on both sides of the passband and improve the selectivity of this filter. In order to inhibit the wireless local area network signal, the rejection band was introduced by adding a loaded stub resonator. Electromagnetic simulations was carded out. The filter has a pass band of 3.1-10.6 GHz, a insertion loss of less than 1 dB, and a notched band of-40 dB at 5.8-5.9 GHz.