In order to protect Swedish waters and coasts, new experimental methods and systems are being developed for the recording of acoustic and electromagnetic signals. These signals may originate from either surface shipping or underwater vessels, as well as from divers or marine life. The systems may be stationary, for example when taking measurements over prolonged periods, or they may be mobile and therefore capable of covering large areas, for example systems designed for autonomous craft. Results of the experimental research are also applicable to areas such as prospecting and oceanography.
In order to extract information from signals recorded by the experimental systems, the signals must be represented, manipulated and transformed by means of various signal processing algorithms. Developments in the field of computer technology mean that ever more advanced signal processing algorithms can be used, which in turn means that existing systems can be improved and given new capabilities. Signal processing is also employed to make reconnaissance systems more robust by making them more resistant to various naturally occurring or deliberate forms of interference.
The development of new sensor systems continues and it is possible to simulate and model signal propagation in the environment where the sensors are designed to operate. Typical Baltic Sea environments are often complicated due to the shallow depth and the many skerries, islands and islets in the coastal waters. The research covers the development of software for acoustic, elastic, and electromagnetic wave propagation. An important component of this work is to understand the source and this involves advanced signature calculations which in many cases may have to take specific account of the environment concerned. The propagation of these waves towards various targets, for example submarines, divers and buried mines, is also modelled using the tools we are developing. Simulation and modelling is also a cost-effective way of assessing the performance and effectiveness of the design of new underwater systems, which is very useful, for example for the Swedish Armed Forces in equipment modernisation and the procurement of new materiel.