The domain decomposition FDTD method (DD-FDTD) is presented for solving complex problems and improving the accuracy of solutions.Based on this idea

the original domain is decomposed into several sub-domains according to the features of the problem.In each sub-domain

the conformal meshes are created in local coordinates and the FDTD computation is carried out independently in local meshes and local time step

and there is no stability concern.In the iteration procedure of FDTD

the data are exchanged between adjacent sub-domains with overlapped meshes.A suitable data-exchanging scheme proposed here integrates the sub-domains and leads to a more exact solution.This greatly increased the calculation efficiency.A 2-D scattering problem is calculated by using this method and the accuracy of the solution validates the usefulness and exactness of this method.