The Localization Algorithm Based on Symmetry Correction for Underwater Acoustic Networks

Underwater localization is an important and fundamental part of the Underwater Acoustic Networks (UANs). The problem we must face is that radio waves and optical waves are heavily attenuated underwater, so acoustic signals become the most common form of communication. However, the speed of sound wave is not constant and will be affected by the environmental factors. The inaccurate sound velocity will have a serious impact on the traditional positioning results. Therefore, the symmetry correction based on least square estimation (SC-LSE) is proposed in this paper. SC-LSE mitigates the influence of the imprecise velocity estimation on the localization by means of a special symmetrical relationship. We consider a realistic case, where the actual speed of sound is uncertain and the unknown nodes may be moving. The simulation results exhibit that our algorithm can achieve good performance and is not sensitive to the change of sound velocity and node movement.