A high frequency sonar simulator for accurate prediction of acoustic system performance in the underwater environment

High frequency (250 kHz-2 MHz) acoustic systems have recognised potential for many areas of underwater working. Currently, much equipment functions at the extreme end of physical limits and all only satisfy part of the operational requirements. Under such circumstances, minor alterations to key parts of any sonar equipment can result in major practical improvements. Conversely, such adjustments can result in catastrophic malfunction unless implemented with a comprehensive understanding of the interactive processes that occur within what is an extremely complex electromechanical system. Clearly, cost effective design and equipment optimisation would be enhanced by the availability of a relevant computer simulator describing the acoustic front end and its interaction with the operating environment, electrical interfacing, processing and subsequent display. This work describes the current development status of such a simulator, as a "state of the art" aid to sonar design engineers. Directed towards multielement array based systems, the work has addressed major inherent difficulties such as the front end transducers and their distribution, spatial field characteristics (including beam steering and focusing), propagation and beam interaction with realistic target structures, in addition to the system electronics and influence of constituent noise on sonar performance.