Pulse-Doppler Radar
Pulse-Doppler is a 4D radar system capable of detecting a target 3D location and its radial velocity (range-rate). The radar transmit short pulses of radio frequency which are partially bounced back by airborne objects or spacecrafts. In a typical operation, the energy returned from a dozen or more pulses are combined using Pulse-Doppler signal processing, based on the Doppler effect, to extract the information. The use of short pulses instead of a continuous wave avoids the risk of overloading computers and operators as well as reduce power consumption. In particular, it reduces enough the microwave power emission and the weight of the radar to make it safe and effective for use on aircraft.
Pulse-Doppler radar has fundamental characteristics that differentiate it from conventional pulse radar, and continuous-wave Doppler radar, which makes it ideal for different applications: improved detection in high-clutter environments, greater track reliability using feedback, passive vehicle type classification, and unattended operation.
In meteorological radars, pulse-Doppler measures instantaneous speed of precipitations at discrete range intervals as the beam is slewed across the sky. Pulse-Doppler radar is also the basis of synthetic aperture radar used in radar astronomy, remote sensing and mapping. In air traffic control, they are used for discriminating aircraft from clutter. This type of radar is crucial for military applications such as airspace surveillance, targeting and look-down/shoot-down, which allows small fast-moving objects to be detected near terrain and weather. It permits detection of targets while eliminating hostile environmental influences, such as reflections from weather, the surface of the earth, and biological objects like birds, and electronic interference, which hide reflected signals from aircraft but which move much slower. A secondary adavantage in military radars is to reduce transmit power while achieving acceptable performance for improved safety of stealthy radar.
Read more about Pulse-Doppler Radar: History, Principle, Signal Processing, Special Consideration, Aircraft Tracking Uses
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