- Infrared signature
The term infrared signature is used by defense scientists and the
military to describe the appearance of objects toinfrared sensors . An infrared signature depends on many factors, including the shape and size of the object,temperature andemissivity , the background against which it is viewed and the waveband of the detecting sensor. As such there is no all-encompassing definition of infrared signature nor any trivial means of measuring it. For example the infrared signature of a truck viewed against a field will vary significantly with changing weather, time of day and engine loading.A military aim in studying infrared signatures is to understand the likely infrared signature of threats (and develop the equipment required to detect them) and to reduce the infrared signature of their own assets to threat sensors. In practice this might mean equipping a warship with sensors to detect the exhaust plumes of incoming anti-ship missiles while also having an infrared signature below the detection threshold of the infrared sensor guiding the missile.
Two fairly successful examples of defining the infrared signature of an object are the apparent temperature difference at the sensor and the contrast radiant intensity (CRI) definitions.
Free Software
* [http://sourceforge.net/projects/osmosis-project/ osmosis] a high performance, free software package for infrared signatures simulations for complex targets
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