Forward Looking Sonar

Contact: A/Prof Paul Teal

Most sonars are used in a ``downward looking'' or ``side scan'' mode, and as a result of boat movement, any area being surveyed is only viewed once. Thus these contrast with forward looking sonar, usually used for collision avoidance, in which the same general area is ensonified multiple times. The fact that an area is ensonified several times means that Bayesian estimation tools can be used for interpreting the returned data -the information gained from one ping being used as the prior for the next. A prototype 30 channel sonar system has been constructed, and trials are in progress. The project is developing and applying mutli-target tracking algorithms to the data. Techniques include the use of the probability hypothesis density (PHD) filter. The projects is also enhancing the techniques to deal with the additional complication of reverberation in shallow water between the sea bottom and sea surface.