  A submarine's sonar team is responsible for detecting, localising and
classifying targets using information provided by the platform's sensor suite.
The information used to make these assessments is typically uncertain and/or
incomplete and is likely to require a measure of confidence in its reliability.
Moreover, improvements in sensor and communication technology are resulting in
increased amounts of on-platform and off-platform information available for
evaluation. This proliferation of imprecise information increases the risk of
overwhelming the operator. To assist the task of localisation and
classification a concept demonstration decision aid (Horizon), based on
evidential reasoning, has been developed. Horizon is an information fusion
software package for representing and fusing imprecise information about the
state of the world, expressed across suitable frames of reference. The Horizon
software is currently at prototype stage.
