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Contemporary radar systems can distinguish chaff from legitimate targets by measuring the Doppler effect; [4] chaff quickly loses speed after leaving an aircraft, and the resulting shift in wavelength of the radar return can be measured. To counter this, a chaff cloud can be illuminated by the defending vehicle with a doppler-corrected ...
A Doppler radar is a specialized radar that uses the Doppler effect to produce velocity data about objects at a distance. [1] It does this by bouncing a microwave signal off a desired target and analyzing how the object's motion has altered the frequency of the returned signal.
The ship then escapes in another direction. The decoy (chaff cloud) should have a larger radar cross-section (RCS) than the target, so the radar tracks it. Corner reflectors have the same effect as chaff but are physically very different. Corner reflectors are many-sided objects that re-radiate radar energy mostly back toward its source.
This is an issue only with a particular type of system; the pulse-Doppler radar, which uses the Doppler effect to resolve velocity from the apparent change in frequency caused by targets that have net radial velocities compared to the radar device. Examination of the spectrum generated by a pulsed transmitter, shown above, reveals that each of ...
Debris and chaff are transient and move in height with time. They are all indicating something actually there and either relevant to the radar operator and/or readily explicable and theoretically able to be reproduced. Doppler radars and Pulse-Doppler radars are extracting the velocities of the targets. Since anomalous propagation comes from ...
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.
If the radar was locked on to the aircraft, it will hopefully remain locked to this second pulse as the aircraft moves away from the original location. Eventually, the aircraft will fall outside the range gate and disappear, while the radar continues tracking the false signal. Thus, the false signal is said to "pull the range gate off the target".
This ability was rendered obsolete by radar. [10] Chaff was invented in Britain and Germany early in World War II as a means to hide aircraft from radar. In effect, chaff acted upon radio waves much as a smoke screen acted upon visible light. [11] The U-boat U-480 may have been the first stealth submarine.