Research On Localization Algorithm In Underwater Acoustic Sensor Networks

Wireless sensor networks (WSN) are self-organized networks with a great deal of small random distributed nodes, which are composed of sensor, data processing and communication modules. In recent years, WSN, especially underwater wireless sensor networks (UWSN) technology has been developed rapidly in military defense, environmental monitoring and many other fields. The research on UWSN has important scientific value and practical value. Nodes localization of WSN is the basis of most of uses in WSN. Target tracking is an important application of WSN, therefore nodes localization and target tracking has been important research direction in the study of WSN. Meanwhile, Compass Navigation Satellites System (CNSS), which started to work in April 2004, is operating stably in mapping, water conservancy, transportation, exploration, national security and many other fields. The system has been playing an important role gradually.The research of this paper is focus on UWSN nodes localization and target tracking algorithm. Considering of the development of CNSS and the particularity of water environment, CNSS is set up as the base of UWSN nodes localization. Methods of nodes localization and target tracking are researched to fit in with the system. The main work includes:A UWSN position system based on CNSS is put forward according to the advantage of CNSS and particularity of UWSN. The framework and function of CNSS-based UWSN position system is described in the article. The feasibility and advantage of the system is analyzed by introducing relevant knowledge of CNSS, development situation and existing problems of UWSN.A cooperative localization method (CL) of nodes based on roundtrip time of flight (RTOF) is used for UWSN. The cost of network is reduced obviously, because many unknown nodes are used for refining the localization precision. Simulation results show that the localization precision is satisfied.A kind of UWSN target tracking method, Voronoi-based cluster and hierarchy (VC-HP) method is presented. Through the layered network management in three-dimensional underwater environment, network can be recovered from failure. Besides that, the lost target can be found again. Simulation shows that this method can get trade-off between track quality and energy consumption and it is fit for application requirements.