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The next example involves a large square metal (PEC) plate of dimensions 5λ₀ × 5λ₀ illuminated by an obliquely incident, plane wave source with θ = 30° measured from the zenith. For this electrically large plate, the physical optics method yields very good results at the main laobe lobe and the first few side lobes. Figures 5 and 6 show the normalized bi-static RCS of the large plate as simulated by [[EM.Libera]] and [[EM.Illumina]]. The two figures correspond to the incident TMz and TEz polarizations, respectively. Note that the maximum RCS is observed at 30° as one would expect. At the grazing angles, one can see significant discrepancies between the asymptotic PO and full-wave Surface MoM results. For comparison, Figure 7 shows a reproduction of the physical optics results given by Ref. [3], which have been calculated analytically using a simple PO approximation of uniform surface currents on the metal plate.

Next, we examine scattering from a large metallic sphere. For this case, we consider a PEC sphere of radius 477.465 mm corresponding to k₀a = 10, at the frequency f = 1GHz. Figure 13 shows the triangular surface mesh of this sphere generated by the [[EM.Libera]] or [[EM.Illumina]] mesh generators. A mesh density of 100 samples/λ₀² has been used for this mesh. Figure Figures 14 and 15 show the bistatic RCS of the metallic sphere as a function of the elevation angle θ for the two cases of TMz and TEz polarizations, respectively. The two figures compare the results computed by [[EM.Libera]]'s surface MOM solver and [[EM.Illumina]]'s Physical Optics (PO) solverand compare them with the simulated results given by Ref. [6], which presents two sets of data, one based on the method of moments (MoM) and the other based on a hybrid PO/MoM/Fock technique. The two data sets in Ref. [6] are almost identical. Like in the previous example, physical optics predicts the RCS over the main beam (or maximum RCS angles) adequately; however, its accuracy degrades over the side lobes.[[EM.Libera]]'s results almost exactly match those of Ref. [6].

Figures 20 19 and 21 20 show the computed bistatic RCS of the cylindrical rod as a function of the elevation angle when the target is illuminated from the bottom by a normally incident plane wave source. The two figures correspond to the bistatic RCS in the two principal planes YZ (φ = 90°) and ZX (φ = 0°), respectively. These figures compare the results simulated by [[EM.Libera]] and [[EM.Tempo]] with those reported in Ref. [7] based on a method of moments (MOM) formulation of bodies of revolution (BOR).

[[Image:ART RCS25.png|thumb|left|480px|Figure 25: Variation of normalized bistatic RCS (σ/λ²) of a long metallic cylindrical rod conesphere illuminated by a normally incident plane source with rounded ends TEz (horizontal) polarization as a function of elevation angle θ in ZX plane (φ = 0°), solid red line: [[EM.Libera]] results, solid blue line: [[EM.Tempo]] results.]]

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