【摘要】 介绍二次有限元法分析波导本征值问题的基本原理和计算过程,编制相应的程序,实例计算了矩形波导的截止频率,并与理论值进行比较;计算了EMC/EM I工程测试中TEM Cell高次模式的截止频率,所获得的计算结果与相关文献中所报道的数据吻合较好,表明该方法的有效性。同时还分析计算了十字形截面的方形同轴电缆线的高阶模式的截止频率。更多还原

【Abstract】 This paper presented the elementary principle and the method of computation for waveguide eigenvalues by using quadric-FEM.In order to demonstrate the availability and the precision in calculation of the method,we calculated the cut-off wavelength of TE-mode in rectangular waveguide and had a comparison with the analytic solution.As an application,we computed the cut-off frequencies of higher order modes in the TEM Cell for EMI/EMC,and the results agreed well with those of the literature [7].From Tab.1 and Tab.2,we see that the quadric-FEM is an effective approach for the calculating waveguide eigenvalues in engineering.At last,we evaluated the cut-off frequencies of higher order modes in transmission line consisting of crisscross and rectangular conductors.更多还原