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Old 12th Mar 2014, 11:17
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awblain
 
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Radars can give elevation (not directly height), return time lag (not directly distance) and frequency shift (not directly line-of-sight speed), if they can form a 2D beam on the sky from a phased-array, broadcast a series of beams at different stacked elevations, or do an old WWII-Freya scan with a dish.

Analysis of this information, and the measured motion on the sky between scans then gives 3-D velocity, distance and height, correcting for refraction, Earth curvature and trigonometric coupling of height and distance to elevation.

Standard rotating antennas with dipole array transmitters, like the old iconic Heathrow radar on the concrete pillar by the tunnel entrance on the terminal island, don't do elevation, and rely on transponder broadcasts.
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