Localization for anchor-free underwater sensor networks

For Underwater Wireless Sensor Networks (UWSN), identifying the location of each sensor node is an important issue, which is also a challenging task. Most of the existing localization schemes assume that the network has a plurality of anchor nodes to assist positioning. Usually, they make use of Autonomous Underwater Vehicle (AUV) or node with special equipment as anchor node, because Global Positioning System (GPS) is invalid in underwater environment. High cost and poor flexibility make them not well suitable for UWSN. In order to overcome this disadvantage, we propose an Anchor-Free Localization Algorithm, called AFLA. It is designed for active-restricted underwater sensor networks. AFLA does not need anchor node’s information, and makes use of the relationship of adjacent nodes. It could be used in both static and dynamic networks. The obtained simulation results indicate that AFLA is an effective localization scheme for UWSN.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► An anchor-free localization algorithm (called AFLA) is designed. ► AFLA is designed for active-restricted underwater sensor networks. ► The localization mechanism for dynamic underwater sensor networks is proposed. ► It solves the problem of lacking anchor nodes in underwater environment.