基于组合多通带谐振器的三频滤波器设计

Design of Triple-Band Filter Based on Assembled Multiband Resonator

为得到三个通带中心频率及带宽均可独立调节的三频滤波器,提出了一种基于组合多通带谐振器的三频滤波器设计方法.首先采用阶跃阻抗谐振器和半波长谐振器构建组合多通带谐振器;然后分别采用级联型和伪交指型的耦合结构设计了两种三频滤波器,每种结构都有足够的自由度来获得所需的带宽和中心频率;最后设计并加工了两个工作在2.45、3.50和5.25GHz的三频滤波器.测量结果与仿真结果吻合良好,验证了文中三频滤波器设计方法的有效性.

In order to obtain triple-band bandpass filters with independently-controlled center frequencies and bandwidths, this paper presents a novel design method of triple-band filters based on the assembled multiband resonator. In this method, first, a stepped impedance resonator and a half-wavelength resonator are both employed to construct an assembled muhiband resonator. Then, two kinds of triple-band filter configurations with cascaded and pseudo- interdigital formats are designed, both of which possess sufficient freedom to satisfy the requirements of bandwidth and center frequency. Finally, two filters operating at 2.45, 3.50 and 5.25 GHz are designed and fabricated. The measured results of the filters accord well with the simulated ones, meaning that the proposed design method is feasible.