FDTD Simulation of Very Large Domains Applied to Radar Propagation over the Ocean

摘要

A domain decomposition method for analyzing very large FDTD domains, tens of thousands of wavelengths long, is demonstrated by application to the problem of RADAR scattering in the maritime environment. Success depends on the elimination of artificial scattering from the "sky" boundary and this is ensured by an ultra-high performance absorbing termination that eliminates this reflection at angles of incidence from normal down to less than 0.2 degrees off grazing. The results are cross-validated at S-Band by comparison to Method of Moments over a 3.6 km flat conducting plane with an inhomogeneous atmosphere, and at X-Band by comparing to another parabolic equation method on propagation through an inhomogeneous atmosphere over a 4km long sea surface. Details of the method are given for the two-dimensional problem (2D). The same techniques used in 2D are being applied to three dimensions (3D).