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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 ...
For basic considerations of the strength of a signal returned by a given target, the radar equation models the target as a single point in space with a given radar cross-section (RCS). The RCS is difficult to estimate except for the most basic cases, like a perpendicular surface or a sphere.
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.
These variations can be exploited to estimate the sea surface wind, i.e. its speed and direction. This estimate process is sometimes termed ' wind retrieval' or ' model function inversion' . This is a non-linear inversion procedure based on an accurate knowledge of the GMF (in an empirical or semi-empirical form) that relates the scatterometer ...
Different radar artifacts cluttering the radar display. Clutter [1] [2] is the unwanted return (echoes) in electronic systems, particularly in reference to radars.Such echoes are typically returned from ground, sea, rain, animals/insects, chaff and atmospheric turbulences, and can cause serious performance issues with radar systems.
This is because the signal strength at the DF receiver, due to a radar transmission, is proportional to 1/R 2 whereas that at the radar receiver from the reflected return is proportional to σ/R 4, where R is the range and σ is the radar cross-section of the DF system. [36]
where Q is the efficiency factor of scattering, which is defined as the ratio of the scattering cross-section and geometrical cross-section πa 2. The term p = 4πa( n − 1)/λ has as its physical meaning the phase delay of the wave passing through the centre of the sphere, where a is the sphere radius, n is the ratio of refractive indices ...