Node Localization Techniques in Underwater Sensor Networks

The localization of non-localized sensor nodes is considered as a vital task in underwater communication, as it functions as the basic building block for several other capabilities, including tracking underwater nodes, coordinating the movements of an array of nodes and locating the underwater targets. Moreover, the localization also plays a key role in optimizing the medium access and routing protocols that facilitates the successful execution of Georouting, which in turn helps to get useful location-aware data. However, the localization is not an easy task as it faces several challenges, such as displacement of sensor nodes by water currents, multipath interference, high propagation delay, and fluctuations in the amplitude, etc. Another major challenge is the accurate determination of sensor node's 3D position coordinates in actual water environment. In this paper an attempt has been made in studying various approaches of existing localization and deployment techniques.