摘要
多层快速多极子法是基于矩量法的快速算法,具有较低的计算复杂度和存储复杂度,被广泛应用于目标电磁散射特性分析。对于复杂结构电磁目标,由于矩阵条件数较差,往往存在迭代收敛慢甚至不收敛的问题。针对这一情况,文中利用快速多极子的近区矩阵,结合稀疏矩阵方程求解构造了一种高效预条件。数值实例表明该方法相比于块对角预条件效果更好,能有效加速多层快速多极子迭代过程。
Based on the method of moment(MoM), the multilevel fast multipole algorithm(MLFMA) has the property of low computation and storage complexity, and it is widely used in calculating electromagnetic scattering problems. However, for a target with complex structure, there will be an ill-conditioned matrix, making the iteration time too long or the problem non-convergence. Considering such situation, we propose a kind of preconditioner combining the near-field matrix and sparse matrix solver for MLFMA. Compared with the block diagonal preconditioned methods, this method has better convergence characteristic.
引文
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