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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 ...
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]
The radar mile is the time it takes for a radar pulse to travel one nautical mile, reflect off a target, and return to the radar antenna. Since a nautical mile is defined as 1,852 m, then dividing this distance by the speed of light (299,792,458 m/s), and then multiplying the result by 2 yields a result of 12.36 μs in duration.
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.
Consider the following example : if the radar antenna is located at around 15 m above sea level, then the distance to the horizon is pretty close, (perhaps 15 km). Ground targets further than this range cannot be detected, so the PRF can be quite high; a radar with a PRF of 7.5 kHz will return ambiguous echoes from targets at about 20 km, or ...