An accelerating technique by same meshes in FEM

An accelerating technique by same meshes in finite element method(FEM) is introduced. By the characteristic of base function depending on geometric form the computing quantities of base function and coefficients matrix are reduced by constructing the same meshes. And farther coefficients matrix of fem quick filling is realized and the quick solving of aim problem is achieved as well. The algorithm is demonstrated by eigen modes solving of the rectangle filling waveguide. The novel method can be extended to the fem solving of other problems.