The variational problem related to the coupled vector wave equations and boundary conditions of circular dielectric waveguide with arbitrary refractive index profile is solved using the finite element method ( fem ) 应用有限元方法求解了任意径向非均匀折射率分布圆柱对称介质波导中纵向场耦合波动方程定解问题所对应的变分问题，该方法不受弱导或高斯模场分布等限制。
