title: Anchor-free localization method for mobile targets in coal mine wireless sensor networks.
abstract: Severe natural conditions and complex terrain make it difficult to apply precise localization in underground mines. In this paper, an anchor-free localization method for mobile targets is proposed based on non-metric multi-dimensional scaling (Multi-dimensional Scaling: MDS) and rank sequence. Firstly, a coal mine wireless sensor network is constructed in underground mines based on the ZigBee technology. Then a non-metric MDS algorithm is imported to estimate the reference nodes' location. Finally, an improved sequence-based localization algorithm is presented to complete precise localization for mobile targets. The proposed method is tested through simulations with 100 nodes, outdoor experiments with 15 ZigBee physical nodes, and the experiments in the mine gas explosion laboratory with 12 ZigBee nodes. Experimental results show that our method has better localization accuracy and is more robust in underground mines.
authors.affiliation: State Key Laboratory of Intelligent Technology and Systems, Tsinghua National Laboratory for Information Science and Technology, Department of Computer Science and Technology, Tsinghua University, Beijing 100084, P.R. China; E-Mail:  x-xu07@mails.tsinghua.edu.cn  (X.X.).
authors.forename: Zhongmin
authors.initials: Z
authors.lastname: Pei
authors.forename: Zhidong
authors.initials: Z
authors.lastname: Deng
authors.forename: Shuo
authors.initials: S
authors.lastname: Xu
authors.forename: Xiao
authors.initials: X
authors.lastname: Xu