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Ultra Wideband Positioning Technology for Accident Ships under Adverse Sea Condition

ABSTRACT Zhang, K.; Shen, C.; Gao, Q.; Zheng, L.; Wang, H., and Li, Z., 2018. Ultra wideband positioning technology for accident ships under adverse sea condition. In: Liu, Z.L. and Mi, C. (eds.), Advances in Sustainable Port and Ocean Engineering. Journal of Coastal Research, Special Issue No. 83, pp. 902–907. Coconut Creek (Florida), ISSN 0749-0208. Aiming at the problem that the current location method has the locating error in the base station and its occlusion region of accident ship nearby, an ultra wideband localization technology for accident ship under adverse sea conditions was proposed. Firstly, this method carried out the NLOS identification of ship accident, and measured and determined the NLOS weighting factor of accident ship through contrasting the proximity of the probability density function of distance measurement under line of sight situation and the probability density function under non line of sight situation. The weighted factor reflected the proportion of NLOS nodes and reference nodes of line of sight in location estimation of accident ship, then the least square algorithm was used to locate the target node. Experimental result shows that the proposed method improves the ship positioning accuracy and improves the time measurement performance.