Conference Paper

Target Localization in Underwater Acoustic Sensor Networks

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Abstract

The underwater target localization problem is one important application for underwater acoustic sensor networks. This paper, based on "underwater acoustic transmission theory", solves the target localization problem. The proposed algorithm firstly studies the principle of underwater acoustics and applies it to set up the model of underwater signal energy transmission. According to the model, the maximum likelihood (ML) method is used to estimate the target position based on measuring the received signal energy by sensor node. We also derivate the Cramer-Rao lower bound (CRB) based signal model in this paper. Lastly, our numerical simulation results have verified the feasibility of the proposed localization algorithm, and have studied the precision performance of the algorithm.

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... Finally, much research deals with the use of wireless sensor networks for target detection, localization and tracking [5], [15]: the nature of the considered sensors (often bearingsonly or range-only) converts the problem into an estimation and deployment problem where the quality of the localization depends strongly on the sensor placement. Such systems are suited to monitor dynamic events, i.e., those that appear to move, whereas we are concerned with the detection and localization of stationary sources. ...
... [6] drive the AUVs according to the sensed measures, directing the vehicles to the detecting targets: the approach provides finer localization of targets than systematic sampling. Finally, much research deals with the use of wireless sensor networks for target detection, localization and tracking [5], [15] : the nature of the considered sensors (often bearingsonly or range-only) converts the problem into an estimation and deployment problem where the quality of the localization depends strongly on the sensor placement. Such systems are suited to monitor dynamic events, i.e., those that appear to move, whereas we are concerned with the detection and localization of stationary sources. ...
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... In underwater acoustic communications, especially at short range, distance measurement is crucial in tracking [1] and sensor localization [2]. Techniques for this on land include Time Difference of Arrival (TDoA), Time of Arrival (ToA), Received Signal Strength (RSS), and Angle of Arrival (AoA). ...
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... Therefore, RSS-based target localization is preferred by researchers due to its low complexity and easy implementation [9][10][11][12]. Based on the received signal strength measurements, the maximum likelihood (ML) method is used to estimate the target position [13], and this method is robust in underwater environments. Although the ML estimator has asymptotically optimal performance, it is non-convex and has multiple local optimal solutions. ...
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This paper addresses the target localization problems based on received signal strength (RSS) measurements in underwater acoustic wireless sensor network (UWSN). Firstly, the problems based on the maximum likelihood (ML) criterion for estimating target localization in cases of both known and unknown transmit power are respectively derived, and fast implementation algorithms are proposed by transforming the non-convex problems into a generalized trust region subproblem (GTRS) frameworks. A three-step procedure is also provided to enhance the estimation accuracy in the unknown target transmit power case. Furthermore, the Cramer-Rao lower bounds (CRLBs) in both cases are derived. Computer simulation results show the superior performance of the proposed methods in the underwater environment.
... Finally, much research deals with the use of wireless sensor networks for target detection, localization and tracking [Liu02,Biao08]: the nature of the considered sensors (often bearingsonly or range-only) turns the problem into an estimation problem and a deployment problem where the quality of the localization depends strongly on the sensor placement. Such systems are suited to monitor dynamic events, i.e. that evolve overtime. ...
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... There are different levels of power absorption in underwater environment that change with depth, frequency and temperature. When an underwater source propagates an acoustic sound, its power intensity will diminish to some extent because of this mentioned absorption [4]. Xavier [11] shows that the attenuation increases rapidly with frequency ...
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