The MOM Solution Combining Hybrid Domain Bases and Wire-grid Model for Scattering by Complex Targets

Abstract

An e-cient basis function is described in this paper for computation of RCS of PEC wire-grid model of aircraft in the resonance domain based on the method of moment (MoM). Al- though many achievements on the wire-grid model had been obtained (1), the numerical solutions of this problem are given based on a new hybrid domain basis function and Galerkin method. The aircraft shape is approximated by a grid of thin wires, the length and the radius of this thin wires must be satisfled some special requirements. Computational results for RCS of canonical wire-grid models of targets are enclosed. The flnal results show that with this hybrid domain basis functions, good agreement with experimental data can be obtained by this technique. DOI: 10.2529/PIERS061205084945 The MoM for the wire-grid model was flrstly presented by J. H. Richmond in 1966. In (1), the RCS of a sphere and a circular plate were calculated by wire-grid model for continuous conducting surfaces using pulse bases and point matching. The reaction technique subsequently proposed in (2) was also a moment method with sinusoidal bases and Galerkin's method, where several wire-grid models of an airplane with increasing details were used to demonstrate the accuracy of the wire-grid reaction technique by comparing computational results with measured data. So, the technique of wire-grid model combined with subdomain bases was widely used in the computation of the RCS for some complex targets in the past years. This paper discusses the use of MoM based on the hybrid domain basis functions in wire-grid models, which comes from the thought of almost-entire-domain described in reference (3). The computational results obtained by this method are compared with experimental data. It is shown that a high e-ciency of calculation could be achieved by using wire-grid models to approximate continuous PEC surfaces, and the feasibility is also verifled by applying this hybrid domain basis functions to accurately model the thin wire structures' axial current. 2. FORMULATION 2.1. Wire-grid model (1{3)