Efficient Electromagnetic Scattering Computation Using the Random Auxiliary Sources Method for Multiple Composite 3-D Arbitrary Objects

The electromagnetic (EM) scattering problem from three-dimensional (3-D) arbitrary composite objects is proposed using the random auxiliary sources (RAS) method. Based on direct application of the boundary conditions with the uniqueness theorem and the use of random equivalent problems concept, more degrees-of-freedom to the sources´ positions are added resulting in significantly efficient solutions with lower memory requirements. The technique does not require any singularity treatment due to placing the equivalent sources away from the boundaries. While boundary conditions are not enforced exactly, an iterative framework is introduced that can achieve an acceptable level of error in their satisfaction for an arbitrary, randomly generated set of equivalent sources. The presented technique promises a significant reduction in the execution time and memory requirements compared to the surface-equivalent-based method of moments (MoM). The solution stability, repeatability, and numerical noise susceptibility are investigated thoroughly through this work. Also, a novel edge correction scheme has been implemented to extend the capabilities of this procedure to structures with sharp edges. The results of the presented technique are compared to series solutions for conducting spheres and a commercially available MoM code for arbitrarily shaped objects and combinations of different materials.