In addition, mobility of nodes is considered as another parameter in this solution. Simulation results on prototype data showed the effectiveness of the proposed method. In addition, it is compared with another well-known method and the results show the outperforming results for the proposed method. | International Journal of Computer Networks and Communications Security VOL. 2, NO. 12, DECEMBER 2014, 414–422 Available online at: ISSN 2308-9830 A Combined Localization-Synchronization Method for Underwater Communication ZAHRA MOUSAVI1 and REZA JAVIDAN2 1, 2 Department of Computer Engineering and Information Technology, Shiraz University of Technology E-mail: 1zmousavi1386@, ABSTRACT In underwater communication usually localization and time synchronization of nodes are important processes which are treated separately. However in Wireless Sensor Networks (UWSNs) saving energy of nodes is another important factor. To save energy, it is an increasing interest to do these works together. In this paper a new method for combined localization and synchronization for communications in UWSNs is proposed. In this method the attribute of sound wave has been considered and stratification effect is used to compensate the bias in range estimates. This is a main important factor that is not considered in other related researches. In addition, mobility of nodes is considered as another parameter in this solution. Simulation results on prototype data showed the effectiveness of the proposed method. In addition, it is compared with another well-known method and the results show the outperforming results for the proposed method. Keywords: Synchronization, Localization, Stratification effect, Underwater Wireless Sensor Network. 1 INTRODUCTION In most underwater communications, localization and clock synchronization are two key elements. Especially in most Wireless Sensor Network (WSN) applications, it is a need for these two services. For instance, TDMA (Time Division Multiple Access), one of the commonly used Medium Access Control (MAC) protocols, often requires precise time synchronization between sensor nodes. Furthermore, most geographic routing algorithms assume the availability of location information [1], [2]. As another .
