Terrestrial Guidance
TERCOM, for "terrain contour matching", uses altitude maps of the strip of land from the launch site to the target, and compares them with information from a radar altimeter on board. More sophisticated TERCOM systems allow the missile to fly a complex route over a full 3D map, instead of flying directly to the target. TERCOM is the typical system for cruise missile guidance, but is being supplanted by GPS systems and by DSMAC, Digital Scene-Matching Area Correlator, which employs a camera to view an area of land, digitizes the view, and compares it to stored scenes in an onboard computer to guide the missile to its target.
DSMAC is reputed to be so un-robust that destruction of prominent buildings in the internal map of the system (by preceding cruise missiles, among other things) will spoil navigation.
Read more about this topic: Missile Guidance, GOLIS Systems
Famous quotes containing the word guidance:
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