Wireless Sensor Networks (WSNs) attract a large variety of applications. The physical localization of sensors is one of the fundamental tasks in such networks. This task is challenging due to technical and financial constraints of nodes that need sophisticated solutions. Existing satellite-based methods might be cost, require high-energy consumption with no guarantee of full coverage of that area. Therefore, other methods, which use the local connectivity information to deduce sensors position, provide an approximate or a relative localization. In this work, we propose a new localization protocol called SL-Free protocol (Self Localization protocol based range-free), which provides a fine localization for node. The main goal of this proposal is to give the most precised coordinates with less cost. The performance study shows that, SL-Free outperforms its peers in terms of precision and energy use.

无线传感器网络（WSN）吸引了各种各样的应用。传感器的物理定位是此类网络中的基本任务之一。由于需要复杂解决方案的节点的技术和财务限制，此任务具有挑战性。现有的基于卫星的方法可能成本高昂，需要消耗大量能源，而不能保证对该区域的完全覆盖。因此，使用本地连接信息推断传感器位置的其他方法可提供近似或相对定位。在这项工作中，我们提出了一种新的本地化协议，称为SL-Free协议（基于自由范围的自我本地化协议），它为节点提供了良好的本地化。该提案的主要目标是以更低的成本提供最精确的坐标。效果研究表明，