Abstract: A novel sparse recursive Cholesky factorization preconditioning technique is proposed for accelerating analyses of radiation problems of wire antennas mounted on large complex platforms with a hybrid method of physical optics and moments (PO-MoM).Based on the physical meanings of the electric field integral equation (EFIE) kernel and neglecting coupling between MoM and PO regions, an approximate sparse matrix of the coefficient matrix derived from the PO-MoM hybrid method is obtained.Inverse of the sparse matrix is then factorized recursively with Cholesky factorization. Thereafter, a preconditioner in a form of successive multiplication is constructed.It is used in a preconditioned generalized minimal residual (GMRES) method to iteratively solve the systems of linear equations.The proposed preconditioning technique is applied to solve radiation problems of antennas mounted on a satellite model and a ship model in electrically large size.Numerical results demonstrate that the new preconditioning technique is efficient in reducing the number of iterations in solving the linear systems derived from PO-MoM.

Key words: wire antenna, PO-MoM, Cholesky factorization, preconditioning, complex platform