一种微带-槽线型宽边耦合结构超宽带滤波器设计

Design of a UWB filter with microstrip-slotline broadside coupling structure

设计了一种微带-槽线型宽边耦合结构超宽带(ultra wide band,UWB)滤波器,该滤波器采用多层结构设计,谐振器由3个微带-槽线型宽带谐振器构成,每个谐振器由上下层面上的弯曲T型微带贴片和中间层的圆形耦合槽构成,并且在带内可以产生2个传输极点。通过多个谐振器的级联,不仅可以增加带内传输极点,增强电路耦合,而且还增大了电路带宽,实现UWB滤波器设计。该UWB滤波器3 dB分数带宽能够达到96%,带内群时延可以达到0.22 ns。仿真数据表明:该UWB滤波器性能优良,具有5G通信低频段应用前景。

This paper introduces a ultra wide band(UWB)filter with microstrip-slotline broadside coupling structure.The filter is different from the structure of the traditional single-layer microstrip planar,and adopts a multi-layer structure.This consists of three bandwidth resonators using microstrip-slot line coupling structure,and each resonator is composed of two curved T-shaped microstrip patches at the top and bottom layers and a circular coupling slot at the mid layer.Two transmission poles can be generated in band.The series connection of multiple resonators not only increases the in-band transmission poles and enhances circuit coupling degree,but also enlarges the circuit bandwidth to realize UWB filter design.The UWB filter has a 3B fractional bandwidth of 96%and an in-band group delay of 0.22 ns.The simulation data shows that the UWB filter has excellent performance and has a prospect of being applied in 5G communication low frequency band.