Thesis (MScEng (Electrical and Electronic Engineering))--Stellenbosch University, 2008. / There is currently a disparity in the amount of research done in underwater communication when compared to terrestrial communication. Therefore, it was the goal of this work to try and make an initial step towards bridging that gap. To start with, an introductory analysis was made of the ocean as a communications medium, focusing on any areas where the ocean characteristics could negatively affect communication. Furthermore, an overview was conducted of current communication schemes, to determine where ocean communication would differ from terrestrial communication, with the idea of determining the limiting parameters of such communication, specifically in terms of protocol design for swarms and sensor networks. Using this research, a n-ary tree-based routing algorithm was designed and incorporated into an overall protocol in line with current ISO convention. The strategy was simulated using the Erlang platform and it was found that underwater communication can be achieved with favourable results. It was however also found that using Erlang as a communications tool is currently not the best option and has various shortcomings, although with further work it could be more usable. The implemented strategy appears eminently feasible and should provide a basis for further research and practical implementation

Operational time is becoming an increasingly important aspect in electronic devices and is also highly relevant in Underwater Acoustic Sensor Networks (UWSN). This thesis contains a study which explores what can be done to de-crease power consumption while maintaining the same functionality of an FPGA inside an underwater sensor-node network. A longer operational time means a more effective system since reconnaissance is one of UWSN’s area of application. The thesis will also cover the implementation of a new sensor-node ‘mode’ which will add new features and increase operational time.