Accurate and efficient evaluation of spatial electromagnetic responses of large scale targets

An error controllable algorithm is proposed to efficiently evaluate two-dimensional (2-D) monostatic radar cross section (RCS) from electrically large and complex targets. The algorithm employs interpolative decomposition (ID) to conduct lowrank decomposition on the excitation matrix consisting of multiple right-hand-sides (RHS's) to figure out the so-called skeleton incidents. After the solutions corresponding to skeletons are obtained, the complete angular responses can be recovered efficiently. The proposed algorithm is error controllable because the accuracy/resolution of the excitation matrix and ID can both be manipulated. The algorithm is efficient in terms of CPU time due to the high efficiency of ID. For large scale problems, the number of unknowns and that of incidents become large, which, in turn, would lead to a huge excitation matrix. A multiinterval variation is proposed to overcome the possible bottle-neck on memory usage. The proposed method is user-friendly because all the tunable parameters are problem independent. Numerical experiments on electrically large and complex targets have been performed to show the performance of the proposed algorithm.