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Radar cross-section (RCS), denoted σ, also called radar signature, is a measure of how detectable an object is by radar. A larger RCS indicates that an object is more easily detected. A larger RCS indicates that an object is more easily detected.
Optical cross section of a flat mirror with a given reflectivity at a particular wavelength () can be expressed by the formula = Where is the cross sectional diameter of the beam. Note that the direction of the light has to be perpendicular to the mirror surface for this formula to be valid, else the return from the mirror would no longer go ...
Taflove and Umashankar developed the first FDTD electromagnetic wave scattering models computing sinusoidal steady-state near-fields, far-fields, and radar cross-section for two- and three-dimensional structures. [14] [15] 1984: Liao et al reported an improved ABC based upon space-time extrapolation of the field adjacent to the outer grid ...
For example, assessing the value of the radar cross section of a plate with the analytical formula: =, where A is the surface of the plate and is the wavelength. The next curve presenting the RCS of a plate computed at 35 GHz can be used as reference example.
The cross-section is the minimum apparent surface area observed in the direction of the radar that must be detectable.. Radar cross section changes with aspect angle. Cross section for anything except a perfect sphere depends upon the aspect angle, which how far the reflector is rotated with respect to the radar pulse.
Radar cross-section – the study of vehicle signature apparent to remote sensing by radar. Fluid mechanics – the study of fluid flow around objects. Specifically aerodynamics concerning the flow of air over bodies such as wings or through objects such as wind tunnels (see also lift and aeronautics).
A simple calculation reveals that a radar echo will take approximately 10.8 μs to return from a target 1 statute mile away (counting from the leading edge of the transmitter pulse (T 0), (sometimes known as transmitter main bang)). For convenience, these figures may also be expressed as 1 nautical mile in 12.4 μs or 1 kilometre in 6.7 μs.
Radar scatterometers use radio or microwaves to determine the normalized radar cross section (σ 0, "sigma zero" or "sigma naught") of a surface. They are often mounted on weather satellites to find wind speed and direction, and are used in industries to analyze the roughness of surfaces.