Research On Localization Algorithm In Underwater Wireless Sensor Networks With Self-healing

As the marine environment ideal media, underwater wireless sensor network inherits the characteristics of the wireless sensor network, which has low-cost, flexibility, fault tolerance, and robustness, etc. It extends the applications of wireless sensor network to underwater environment. The information collected by nodes in underwater wireless sensor network will make sense in case the locations of corresponding nodes can be obtained, this is the premise to achieve the underwater wireless sensor network application. Hence node localization is viewed as a key technology that has been widely studied.Underwater acoustic channel has many characteristics, for example, big propagation delay, less bandwidth, serious path loss, and multi-path effects, etc,in addition, the nodes in network are more likely to be able to move, and it is difficult to obtain its moving rules. These characteristics make a lot of research achievement of wireless sensor network based on land cannot not perfectly suitable for underwater.Based on the research at home and abroad of localization algorithm in underwater wireless sensor networks, this paper has presented a localizationalgorithm in underwater wireless sensor networks with self-healing(SLA). When deploying nodes, there is no difference between every node in this algorithm, we find the anchor nodes through k-node coverage algorithm to make maximum common sensor nodes covered by four anchor nodes. Anchor nodes are capable of communicating with surface buoys and localizing themselves, then common nodes obtain at least four anchors nodes’ location information to localize themselves through quadrilateration, these four anchors nodes are not in the same plane. This algorithm also can find substitutes for a low-energy or sudden-crash anchor node to localize the ordinary nodes covered by this anchor node, this is done in order to avoid repeating the step: find the anchor nodes, and reduce the location error cause by the anchor nodes since they are being exhausted or sudden crash.Through using the MATLAB tool to simulate the SLA localization algorithm and comparing the localization algorithm for large-scale underwater sensor networks(LSL). The simulation results show that the SLA algorithm can improve the positioning accuracy and localization coverage comparing with LSL algorithm, and the SLA algorithm is suitable for the slow flow velocity of underwater environment.