A practical localization solution for wireless sensor networks deployed in linear topography

In this paper, we propose a practical range-free localization solution for wireless sensor networks (WSNs). Different from existing localization approaches, the proposed solution is specially designed for an ultra sparse mobile WSNs deployed in coal mine tunnels with linear topography. To obtain more reference information requited for localization with limited anchor nodes, the proposed solution sets asymmetrical transmission range for the sensor nodes and makes best use of a priori knowledge about the location of the anchor nodes. Numerous real measurements and real localization experiments were made in a coal mine tunnel in the ShanDong province, China. The experimental results show that our proposed solution achieves a high localization accuracy with an error less than 13% of the transmission range of the anchor nodes, while, the traditional range-free solution, i.e., Ad-Hoc Positioning System, has an error about 44% of the transmission range under the same conditions.