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A simple calculation reveals that a radar echo will take approximately 10.8 μs to return from a target 1 statute mile away (counting from the leading edge of the transmitter pulse (T 0), (sometimes known as transmitter main bang)). For convenience, these figures may also be expressed as 1 nautical mile in 12.4 μs or 1 kilometre in 6.7 μs.
An object at height h above the ground and slant range R forms an angle α that can be calculated through sin α = h / R.By re-arrangement, R = h / sin α, or R = h csc α. The radar equation states that the signal received from an object, P e, varies inversely with the 4th power of range and directly as the square of the antenna gain, G, such that P e ~ G 2 / R 4.
Radar is a system that uses radio waves to determine the distance (), direction (azimuth and elevation angles), and radial velocity of objects relative to the site. It is a radiodetermination method [1] used to detect and track aircraft, ships, spacecraft, guided missiles, motor vehicles, map weather formations, and terrain.
However, since humans reflect far less radar energy than metal does, these systems require sophisticated technology to isolate human targets and moreover to process any sort of detailed image. Through-the-wall radars can be made with Ultra Wideband impulse radar, micro- Doppler radar , and synthetic aperture radar (SAR).
The frequency of radio waves used by most radars, in the form of microwaves, propagate in straight lines.This generally limits the detection range of radar systems to objects on their horizon (generally referred to as "line of sight" since the aircraft must be at least theoretically visible to a person at the location and elevation of the radar transmitter) due to the curvature of the Earth.
The mooring systems contain a large winch with 25,000 feet (7,600 m) of tether cable. Operational availability is generally limited only by the weather (60 percent standard) and routine maintenance downtime. The aerostats are stable in winds below 65 knots (120 km/h). Aerostat and equipment availability averages more than 98 percent system-wide.
Optimized as a mobile radar for uncrewed remote-controlled applications as a "gap-filler" in air defense early warning systems concentrating on small, low-flying targets over a long distance. It can be employed as a coastal surveillance radar where targets are small surface vessels and sea-skimming missiles or aircraft. A new antenna extends ...
The bandwidth of a chirped system can be as narrow or as wide as the designers desire. Pulse-based UWB systems, being the more common method associated with the term "UWB radar", are described here. A pulse-based radar system transmits very short pulses of electromagnetic energy, typically only a few waves or less.