![]() ![]() Doppler has maximum detrimental effect on moving target indicator systems, which must use reverse phase shift for Doppler compensation in the detector.ĭoppler weather effects (precipitation) were also found to degrade conventional radar and moving target indicator radar, which can mask aircraft reflections. ![]() Fast-moving objects cause a phase-shift on the transmit pulse that can produce signal cancellation. The reason was traced to Doppler effects that degrade performance of systems not designed to account for moving objects. The earliest radar systems failed to operate as expected. Besides the above conventional surveillance applications, pulse-Doppler radar has been successfully applied in healthcare, such as fall risk assessment and fall detection, for nursing or clinical purposes. In air traffic control, they are used for discriminating aircraft from clutter. Pulse-Doppler radar is also the basis of synthetic aperture radar used in radar astronomy, remote sensing and mapping. Pulse-Doppler techniques also find widespread use in meteorological radars, allowing the radar to determine wind speed from the velocity of any precipitation in the air. A secondary advantage in military radar is to reduce the transmitted power while achieving acceptable performance for improved safety of stealthy radar. This gives pulse-Doppler radars " look-down/shoot-down" capability. As the ground moves at the same speed but opposite direction of the aircraft, Doppler techniques allow the ground return to be filtered out, revealing aircraft and vehicles. However, this only worked when the radar antenna was not pointed down in that case the reflection off the ground overwhelmed any returns from other objects. Earlier radars had used pulse-timing in order to determine range and the angle of the antenna (or similar means) to determine the bearing. Pulse-Doppler systems were first widely used on fighter aircraft starting in the 1960s. The first operational pulse-Doppler radar was in the CIM-10 Bomarc, an American long range supersonic missile powered by ramjet engines, and which was armed with a W40 nuclear weapon to destroy entire formations of attacking enemy aircraft. It combines the features of pulse radars and continuous-wave radars, which were formerly separate due to the complexity of the electronics. Type of radar system Airborne pulse-Doppler radar antennaĪ pulse-Doppler radar is a radar system that determines the range to a target using pulse-timing techniques, and uses the Doppler effect of the returned signal to determine the target object's velocity. ![]()
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