一种微波及毫米波滤波器的精确设计方法

One Kind of Rigorous Design Method for Microwave and Millimeter-wave Filters

介绍了一种微波及毫米波滤波器精确设计方法:由滤波器的原型参数,导出滤波器的广义阻抗变换系数;采用模匹配法或耦合积分方程技术等数值算法精确计算各个耦合结的S参数,进而转换成广义阻抗变换系数;通过插值,获得满足原型要求的滤波器各个耦合结的结构尺寸以及谐振腔长度,将结构参数代入模匹配程序、HFSS或CST软件进行分析,分析结果与预期值一致。设计了26GHz矩形波导带通滤波器,模匹配法和HFSS以及CST软件的仿真结果、测试数据与设计要求一致,说明该种设计方法是有效的。

A kind of rigorous design method for microwave and millimeter-wave filters is presented. The element values for distributed low-pass prototype filter are transformed into general K-inverters. Coupling junctions are computed by Mode-Matching Technique （MMT） or Coupled Integral Equations Technique （CIET） to achieved the exact S parameters and K-inverters corresponding. All dimensions of coupling junctions and the length of resonators are obtained by using interpolation, and the filter is simulated by MMT program, HFSS or CST software, the simulation result agree well with the predicted values, and optimization is not needed during the design progress. A 26GHz rectangular waveguide band-pass filter is designed, both the simulation result by MMT, HFSS and CST and measured date keep good agreement with prototype values. This show that the design method is valid.