L-MAC: Localization packet scheduling for an underwater acoustic sensor network

This article concerns the problem of scheduling the localization packets of the anchors in an underwater acoustic sensor network (UASN). Knowing the relative positions of the anchors and their maximum transmission range, we take advantage of the long propagation delay of underwater communication to minimize the duration of the localization task. First, we formulate the concept of collision-free packet transmission for localization, and we show how the optimum solution can be obtained. Furthermore, we propose two low-complexity algorithms, and through comprehensive simulations we compare their performances with the optimal solution as well as other existing methods. Numerical results show that the proposed algorithms perform near optimum and better than alternative solutions.