在计算任意波导截面TM波截止波数的问题上,矩量法不可避免的要处理奇异点的问题,因此在快速性和简洁性上均存在很大不足。本文提出了一种便捷的计算方法:首先推导出相应截止波数下波导的电场积分方程,采用Gauss-Legendre公式将积分数值化,然后运用矩量法进行处理后得到一个矩阵方程,最后利用迭代法找出这个矩阵的特征值,从而避开了奇异点使得问题的求解更加便捷。 In calculating the wave number of the TM wave of an arbitrary waveguide cross section, the moment method inevitably needs to deal with the problem of singular points. Therefore, there is a great deficiency in the quickness and simplicity. In this paper, a convenient method of calculation is proposed. Firstly, the electric field integral equation of the waveguide at the cut-off wave number is deduced. The Gauss-Legendre formula is used to quantize the integral and then a matrix equation is obtained by the method of moment method. Finally, Finding the eigenvalues ​​of this matrix avoids the singularities that make solving the problem easier.