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An acoustic signature can be pinpointed by triangulation

Author: Martin Su
Date: 06-13-12 17:05

To finish the discussion of precisely locating the position of a DDG-1000 or any other large capital ship, the use of triangulation from multiple acoustic detectors (whether buried in the seabed like the American SOSUS/"Sound Surveillance System" system, buoys, or submarines) can easily pinpoint a DDG-1000.

A simpler method is to use satellites with infrared detectors and look at the ocean. You can't miss the hot infrared signature of 78-MegaWatt engines from a DDG-1000 against the background of cold ocean water.

Assuming the U.S. shoots down all Chinese infrared satellites, it is a simple matter to see a DDG-1000 with the infrared detectors on a fighter aircraft or UAV. See FLIR (forward looking infrared) citation below).

Excerpt for FLIR: "detect warm objects against a cooler background"

I think 78 MegaWatts blazing against a background of cool ocean water is impossible to miss.

Also, see IRST (infra-red search and track) citation below. The IRST on a jet fighter can detect the small heat emissions from an enemy fighter or helicopter. Detecting a 78-MegaWatt 15,000-ton ship is like looking at the Sun. You have to be blind not to see it.

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http://en.wikipedia.org/wiki/Forward_looking_infrared

"Forward looking infrared (FLIR) cameras, typically used on military aircraft, use an imaging technology that senses infrared radiation.[1]

http://i.imgur.com/EQgeu.jpg
Navigation infrared pod by Thales

The sensors installed in forward looking infrared cameras, as well as those of other thermal imaging cameras, use detection of infrared radiation, typically emitted from a heat source, to create the "picture" assembled for the video output, they can be used to help pilots and drivers steer their vehicles at night, and in fog, or detect warm objects against a cooler background. The wavelength of infrared that thermal imaging cameras detect differs significantly from that of night vision, which operates in the visible light and near infrared ranges (0.4 to 1.0 μm)."

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http://en.wikipedia.org/wiki/Infra-red_search_and_track

"An infra-red search and track (IRST) system (sometimes known as infra-red sighting and tracking) is a method for detecting and tracking objects which give off infrared radiation such as jet aircraft and helicopters.[1]

http://i.imgur.com/EQM2Y.jpg
IRST sensor on the Su-27.

IRST is a generalized case of forward looking infrared (FLIR), i.e. from forward-looking to all-round situational awareness. Such systems are passive, meaning they do not give out any radiation of their own, unlike radar. This gives them the advantage that they are difficult to detect.

However, because the atmosphere attenuates infra-red to some extent (although not as much as visible light) and because adverse weather can attenuate it also (again, not as badly as visible systems), the range compared to a radar is limited. Angular resolution at short ranges is better than radar due to the shorter wavelength."

Martin Su

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