Potential approaches for the simulation of the effect of atmospheric turbulence and target speckle on active imaging systems are considered. In particular, computationally tractable methods of applying representative degradation to simulated burst illumination laser imagery are investigated. This is motivated by the fact that the traditional phase screens approach for the simulation of the effect of a turbulent atmosphere on light propagation can require large computing resources to implement parameter sets approaching those appropriate for realistic scenarios. This is undesirable for scene simulation applications where there are typically already considerable demands on computing resources. This is the context in which the various options considered are assessed.
Several of the sensor technologies employed for producing hyperspectral images make use of dispersion across an array to generate the spectral content along a 'line' in the scene and then use scanning to build up the other spatial dimension of the image. Infrared staring arrays rarely achieve 100% fully functioning pixels. In single-band imaging applications 'dead' elements do not cause a problem because simple spatial averaging of neighboring pixels is possible (assuming that a pixel is similar in intensity to its neighbors is a reasonably good approximation). However, when the array is used as described above to produce a spectral image, dead elements result in missing spatial and spectral information. This paper investigates the use of several novel techniques to replace this missing information and assesses them against image data of different spatial and spectral resolutions with the aim of recommending the best technique to use based on the sensor specification. These techniques are also benchmarked against naive spatial averaging.
This paper describes algorithm development work undertaken out for the long-range detection and tracking of air targets in an air to air scenario. Algorithm developments to operate in the search, detect and track modes of an IR search and track equipment are described. In particular, recent work in a variation of the technique known as track before detect has demonstrated good performance in this role. The result of some of this work, derived from demonstration of the algorithms against imagery from airborne trials of flying IRST equipment are presented here.