A hybrid KA‐MoM algorithm for computation of scattering from a 3‐D PEC target above a dielectric rough surface

Abstract

[1] A new hybrid analytical-numerical iterative algorithm, which combines the Kirchhoff approximation (KA) and the Method of Moment (MoM), is developed for computing the electromagnetic scattering from a three-dimensional (3-D) perfect electric conducting (PEC) target above a 2-D infinite randomly rough dielectric surface. The equations of difference scattering due to the target presence above the rough surface are derived. The induced difference fields on the rough surface due to the interactions between the target and the rough surface are calculated by using the KA method. The excitation term on the right-hand-side (RHS) of target's surface integral equation (SIE), which contains the difference scattering of the rough surface, is then updated for calculating new target currents with the Conjugate Gradient (CG) procedure. Then the target currents are used to compute the difference field induced on the rough surface with the KA method. Multiple iterations take account of the multiorder interactions between the target and the underlying rough surface. Numerical quadrature upon the rough surface is performed only once to compute the coupling scattering field from the rough surface to the target, and it takes N steps (N is the discretized mesh number of rough surface). By using this hybrid KA-MoM algorithm, the requirements of memory and CPU time can be reduced significantly. Moreover, the validity conditions and the convergence performance of this hybrid algorithm are also discussed. With Monte-Carlo generations of randomly rough surfaces, bistatic scattering from different-shaped targets above a Gaussian rough surface is numerically simulated. Finally, dependence of bistatic scattering pattern on the surface dielectric property and the target geometry is discussed.

Sampling point selections scheme of the MBPE for calculating the monostatic RCS by the objects on a rough surface

“…( ) _N(s)_ No+NIS+N2S 2 + ... N n s n Is--2 d l d D(s) Do +D1s+D2s +···D d _ IS -+s (1) where I represents the equivalent electrical current and magnetic current, and S denotes the incident angle or wave's frequency. The total number of the sample points is m, where m=n+d+l…”

An Investigation on Numerical Characterization of Scattering From Target in a Dielectric Rough Soil Surface

“…For the targets and rough surface composite scattering, considerable contributions have been made and several methods have been presented during these years, such as MOM [14,15], parallel MOM [16], finite-element (FEM) method [17], finite difference time domain (FDTD) method [18], hybrid SPM/MOM technique [19], hybrid KA/MOM technique [20], hybrid PO/MOM technique [21], reciprocity theorem [22], Generalized forward-backward method (GFBM) [23,24], Mode-expansion method [25], fast iterative approach [26], bidirectional analytic ray tracing method [27], etc. Although the aforementioned numerical methods are of respective important advantages, but some of them are fast but not exact enough, or some of them are exact but not fast enough, therefore, it should be make sense in contributing efforts to investigate and attempt to improve the efficiency and accuracy of the adoptive scheme.…”

Electromagnetic Interactions Analysis Between Two 3-D Scatterers Using the E-Pile Method Combined With the Po Approximation

“…Some methods have been developed for the efficient analysis of composite scattering for a two-dimensional problem (2-D) [1][2][3][4][5][6][7][8][9]. Other examples for a three-dimensional problem (3-D) can be found in [10][11][12][13][14][15][16][17]. However it is important for practical application to study the case of 3-D problem.…”

“…For example Ye et al proposed a hybrid method combining analytic Kirchhoff Approximation (KA) and MoM to study the scattering from 3-D perfect electric target above a 2-D dielectric rough surface [10]. In [11] a half-space Green function with the rough surface interface is first derived from the KA, then the method of moments is applied to analyze the scattering for a 3-D problem.…”