一种基于曲线拟合的微波滤波器参数提取方法

摘要

传统的微波滤波器参数提取方法依赖复杂的优化算法,或不适用于有耗情况.针对该问题,提出了一种新的微波滤波器参数提取方法.首先采用曲线拟合技术提取出滤波器端口的加载相位,并对谐振腔的无载品质因数进行估计,然后根据滤波器的全波仿真数据,利用最小二乘法拟合出其对应的导纳参数,进而得到所需的耦合矩阵.采用该方法对两种复杂结构微波滤波器的仿真数据进行了参数提取,结果吻合良好.%The traditional pamieter extraction for microwave filters usually depends on complicated optimization, or it is not suitable for lossy condition. This paper presents a new parameter extraction method for microwave filter design. The phase loading effect is analyzed and removed by using curve fitting technology, and then the unloaded quality factor of lossy microwave resonator is estimated. By making use of the least squares fitting method, admittance parameters of the filter can be extracted according to the EM simulation data, and then the coupling matrix is obtained from these parameters. The proposed approach is used to extract the parameters from EM simulation data of two kinds of microwave filters with a complicated structure. Extracted results aggree well with the simulation.