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In a conical system, as the rotating flow moves towards the narrow end of the cyclone, the rotational radius of the stream is reduced, thus separating smaller and smaller particles. The cyclone geometry, together with volumetric flow rate, defines the cut point of the cyclone. This is the size of particle that will be removed from the stream ...
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.
A radar system uses a radio-frequency electromagnetic signal reflected from a target to determine information about that target. In any radar system, the signal transmitted and received will exhibit many of the characteristics described below.
An airborne engine drives the generator, supplied by a 100-gallon diesel fuel tank. Beginning in the late 1990s, the aerostat sites were equipped with Lockheed Martin 420K aerostats. This version carries the Lockheed Martin L-88, a surveillance radar with a range of 370 km (200 nm), as its primary payload.
The civilian microwave landing system uses PESA transmit-only arrays. A PESA contrasts with an active electronically scanned array (AESA) antenna, which has a separate transmitter and/or receiver unit for each antenna element, all controlled by a computer; AESA is a more advanced, sophisticated versatile second-generation version of the ...
AN/APN-81 Doppler radar navigation system, mid-1950s. Doppler radar tends to be lightweight because it eliminates heavy pulse hardware. The associated filtering removes stationary reflections while integrating signals over a longer time span, which improves range performance while reducing power. The military applied these advantages during the ...
Most small engines use a governor to maintain a constant engine speed under varying loads. Some engines also have a mechanism for the user to adjust the engine speed. Rather than directly controlling the opening of the carburetor throttle, this is usually achieved by adjusting the governor, which in turn regulates the engine speed higher or lower.
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.