Abstract:The Domain Decomposition FDTD (DD-FDTD) method is presented for solving complex 3-D problems and improving the accuracy of solutions. According to the features of the problem, the original domain is decomposed into several sub-domains. In each sub-domain, the conforrnal meshes are created in local coordinates and the FDTD computation is carried out independently in local meshes. In the iteration procedure of FDTD, the data are exchanged between adjacent sub-domains with overlapped meshes. An interpolating and error-modifying scheme proposed here integrates the sub-domains and leads to a more exact solution. A complex 3-D aperture antenna problem is calculated by using this method and the accuracy of the solution validates the usefulness and exactness of this method.