Hybrid IE-DDM-MLFMA with forward-backward method for conducting body of translation

In this paper, a hybrid scheme named IE-DDM-MLFMA with forward-backward method is proposed to calculate the scattering from the perfectly electric conducting body of translation. The computational body of translation can be partitioned into translational non-overlapping subdomains. Each of integral equation systems are solved separately, thus reducing the complexity of the original problem Moreover, by applying two sets of MLFMA grids, a more efficient matrix-vector multiplication is implemented because of the translation invariant feature of each subdomain. The main advantage offered by this technique is a reduction in memory requirements. For the solution of the resulting linear systems we describe appropriate iterative solution strategies using generalized forward-backward method. At the same time, the iterative procedure for each subdomain is accelerated by block-diagonal preconditioner and parallel strategy based on OpenMP. Numerical examples are presented to demonstrate the efficiency of the present method.