Underwater Acoustic Networks Discovery Protocol and Localization

Knowledge of node location in sub-sea networks is essential for many applications for which sensor networks can be used. The use of GPS that position determination above the sea surface is easily resolved. Unfortunately, using GPS in the sub-sea environment is impossible and positioning requires the use of special methods. One of the major challenges in the underwater acoustic networks (UANs) area of research is the development of a networking protocol that can cope with the management of a dynamic sub-sea network. We propose a scheme to perform node discovery, using only one seed node (primary seed) in a known position. The discovery protocol can be divided into two parts: First, building up the relative co-ordinate system. Second, involving more remote nodes becoming seed nodes for further discoveries. Four different algorithms have been investigated; (i) Farthest/Farthest Algorithm, (ii) Farthest/Nearest Algorithm, (iii) Nearest/Farthest Algorithm and (iv) Nearest/Nearest Algorithm. We investigated the performances of random and fixed (grid) network topologies. Different locations of the primary seed node were exercised and statistics for node discovery are reported.