根据频率变换，以阶跃阻抗谐振器作为腔体滤波器的基本谐振单元设计了一种带有交叉耦合的双通带腔体滤波器. 根据设计指标，用频率变换方法得到双通带腔体滤波器的设计参数，利用三维仿真软件HFSS 对双通带滤波器进行建模并仿真. 仿真结果与ADS 中原理电路得到的理论结果基本吻合，证明了该方法的可行性. 仿真
结果还表明，不仅滤波器的实际尺寸明显减小，而且由于引入了交叉耦合，滤波器的带外抑制能力得以提高，满足了滤波器体积小以及带外选择性好的设计要求.
Using stepped impedance resonators (SIR) as a basic resonator unit of cavity filter, a cross-coupling dual-band cavity filter is designed based on frequency transformation. According to the filter specifications,the design parameters of dual-band filter are calculated using frequency transformation. A model of SIR
cross-coupling dual-band cavity filter is then established and simulated by the 3D simulation software HFSS.Simulation results show good agreement with the result of schematic circuit in ADS, indicating that the method is valid and feasible. The simulation shows that the filter size is significantly reduced, while the restrain ability of stop-band is enhanced due to cross coupling. Thus the requirements of small size and good stop-band performance of the filter are met.
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