基于多模谐振器的超宽带滤波器设计

Ultra-wideband Filter Design based on Multi-mode Resonator

基于多模谐振器理论设计一款结构新颖的超宽带(ultra wide band,UWB)带通滤波器,通过在传统的双模谐振器上加载阶跃阻抗枝节得到。该滤波器尺寸为23.8 mm×9.7 mm,测试的3 dB带宽范围为2.60~10.62 GHz,相对带宽约为121%,中心频率6.61 GHz处的插入损耗为-2.1 dB,通带内群延时小于0.78 ns。此外,滤波器的上下阻带均能产生传输零点,有效地提高了滤波器的频率选择性。该滤波器适宜用在超宽带系统中。

An Ultra Wide Band(UWB) bandpass filter with a novel structure was designed based on the theory of multimode resonator,which is obtained by loading the step impedance branches on the basis of the traditional dual-mode resonator.The size of the filter was 23.8 mm×9.7 mm,and the tested 3 dB bandwidth range was 2.60-10.62 GHz,the relative bandwidth is about 121%,the insertion loss at the center frequency of 6.61 GHz is-2.1 dB,and the group delay in the passband is less than 0.78 ns.In addition,the upper and lower stopbands of the filter can generate transmission zeros,which effectively improves the frequency selectivity of the filter.The filter is suitable for use in the UWB systems.