摘要
传输线理论分析法由于未考虑到滤波器中不连续性结构所带来的传输损耗,往往其分析结果不够准确。针对这一问题,提出了一种新的平行耦合带状线带通滤波器的分析方法。在已获得的带状线不连续性等效电路模型基础上,运用传输线基本理论推导出了附加开路线的平行耦合带状线传输矩阵计算公式,将平行耦合带状线带通滤波器等效成单根带状传输线子网、阶梯跳变子网以及附加开路线的平行耦合带状线子网的级联,通过上述多个级联子网的传输矩阵相乘得到该滤波器的散射参数。实例验证结果表明,该方法计算结果与IE3D软件仿真结果吻合较好,且该滤波器散射参数的平均误差小于2%。
The analytical method of the transmission line theory is not accurate because the transmission loss of the discontinuous structure in the filter is not taken into account,and a new analytical method of the parallel coupled stripline band-pass filter is proposed for this problem.The formulas for calculating transmission matrix of the parallel coupled striplines with open lines are derived based on the obtained stripline discontinuity equivalent circuit model.The parallel coupled stripline band-pass filter is equivalent to the cascade of single stripline subnet,step subnet and parallel coupled stripline subnet with open lines,and the scattering parameters of the filter are obtained by multiplying the transmission matrix of the above cascaded subnets.Through the practical example,it is found the results of obtained method in this paper are in good agreement with IE3 D software simulation results,and the average error of scattering parameters for the filter is less than 2%.
引文
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