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  2. Radar cross section - Wikipedia

    en.wikipedia.org/wiki/Radar_cross_section

    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.

  3. Optical cross section - Wikipedia

    en.wikipedia.org/wiki/Optical_cross_section

    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 ...

  4. Finite-difference time-domain method - Wikipedia

    en.wikipedia.org/wiki/Finite-difference_time...

    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 ...

  5. Pulse-Doppler radar - Wikipedia

    en.wikipedia.org/wiki/Pulse-Doppler_radar

    σ = radar cross section, or scattering coefficient, of the target, F = antenna pattern propagation factor, D = Doppler filter size (transmit pulses in each Fast Fourier transform), k B = Boltzmann constant, T = absolute temperature, B = receiver bandwidth (band-pass filter), N = noise figure.

  6. Radar engineering - Wikipedia

    en.wikipedia.org/wiki/Radar_engineering

    The radar frequency is also chosen in order to optimize the radar cross-section (RCS) of the envisioned target, which is frequency-dependent. Examples of propagation windows are the 3 GHz (S), 10 GHz (X), 24 GHz (K), 35 GHz (Ka), 77 GHz (W), 94 GHz (W) propagation windows.

  7. Envelope (radar) - Wikipedia

    en.wikipedia.org/wiki/Envelope_(radar)

    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.

  8. Radar - Wikipedia

    en.wikipedia.org/wiki/Radar

    σ = radar cross section, or scattering coefficient, of the target; F = pattern propagation factor; R t = distance from the transmitter to the target; R r = distance from the target to the receiver. In the common case where the transmitter and the receiver are at the same location, R t = R r and the term R t ² R r ² can be replaced by R 4 ...

  9. Aerospace engineering - Wikipedia

    en.wikipedia.org/wiki/Aerospace_engineering

    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).