Adaptive multiscale moment methods for analyzing em scattering from electrically large perfectly conducting objects

Three types of adaptive multiscale moment methods are presented here for analyzing electromagnetic scattering from perfectly conducting two-dimensional electrically large objects. The conducting structures are assumed to be in a free-space medium and is illuminated by a TM plane wave. The three algorithms decompose the conventional method of moment matrix into a scaled-block matrix through a matrix multiplication. The numbers of unknowns corresponding to the linear equations at increasing scales can be automatically reduced by using a suitable threshold and the solution obtained from previous scales. Numerical results for the monostatic as well as bistatic radar cross section of several electrically large objects are presented. Comparison has been made with respect to the numerical solution obtained by the moment method. The objective of this paper is to illustrate that a possibility exist for efficiently reducing the size of the linear equations in an automatic fashion utilizing the adaptive multiscale moment methods.