An ongoing challenge for many military imaging systems is the detection and classification of weak target signatures in a cluttered environment. In such cases, the use of image contrast and relative target motion alone does not always provide a sufficient level of target discrimination to give operational confidence and it is therefore necessary to consider the use of other discriminatory scene information. Polarisation is one such source of information and this paper reports on an extensive series of polarimetric trials undertaken across the visible, NIR, SWIR, MWIR and LWIR spectral bands. Using this data, the benefits and limitations of polarisation discrimination are reviewed in the context of practical military scenarios. It is shown that polarisation signatures vary with viewing geometry and atmospheric conditions. This would lead to an unpredictable performance level if the sensor discrimination was based solely on polarisation. However, by carefully combining polarisation with other scene information, useful operational benefits can be obtained and this is illustrated through a consideration of different data fusion approaches.
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