=== Radar Cross Section ===
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[[File:wire_pic49.png|thumb|300px|[[MoM3D Module]]'s RCS dialog]]
When the wire-frame structure is excited by a plane wave source, the calculated far field data indeed represent the scattered fields. EM.CUBE calculates the radar cross section (RCS) of a target, which is defined in the following manner:
:<math> \sigma = 4\pi R^2 \cdot \frac{|E_{scat}|^2}{|E_{inc}|^2} </math><!--[[File:rcs_equation.png]]-->
EM.CUBE calculates three RCS quantities: the φ and θ components of the radar cross section as well as the total radar cross section: σ<sub>θ</sub>, σ<sub>φ</sub>, and σ<sub>tot</sub>. In addition, EM.CUBE [[MoM3D Module]] calculates two types of RCS for each structure: '''Bi-Static RCS''' and '''Mono-Static RCS'''. In bi-static RCS, the structure is illuminated by a plane wave at incidence angles θ<sub>0</sub> and φ<sub>0</sub> and the RCS is measured and plotted at all θ and φ angles. In mono-static RCS, the structure is illuminated by a plane wave at incidence angles θ<sub>0</sub> and φ<sub>0</sub> and the RCS is measured and plotted at the echo angles 180°-θ<sub>0</sub> and φ<sub>0</sub>.It is clear that in the case of mono-static RCS, the Wire MoM simulation engine runs an internal angular sweep, whereby the values of the plane wave incidence angles θ<sub>0</sub> and φ<sub>0</sub> are varied over the intervals [0°, 180°] and [0°, 360°], respectively, and the backscatter RCS is recorded.
NOTE: Computing the 3-D mono-static RCS may take an enormous amount of computation time.
[[File:wire_pic49.png]] [[File:wire_pic50_tn.png]]
The [[MoM3D Module]]'s RCS dialog and a Figure: A half-wave wire connected to a metal plate illuminated by an obliquely incident plane wave.
[[File:wire_pic51_tn.png|260px]] [[File:wire_pic52_tn.png|260px]] [[File:wire_pic53_tn.png|260px]]