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Báo cáo hóa học: " Hop-distance relationship analysis with quasi-UDG model for node localization in wireless sensor networks"

Tuyển tập các báo cáo nghiên cứu về hóa học được đăng trên tạp chí hóa hoc quốc tế đề tài : Hop-distance relationship analysis with quasi-UDG model for node localization in wireless sensor networks | Gao et al. EURASIP Journal on Wireless Communications and Networking 2011 2011 99 http jwcn.eurasipjournals.eom content 2011 1 99 o EURASIP Journal on Wireless Communications and Networking a SpringerOpen Journal RESEARCH Open Access Hop-distance relationship analysis with quasi-UDG model for node localization in wireless sensor networks Deyun Gao1 Ping Chen2 Chuan Heng Foh3 and Yanchao Niu1 Abstract In wireless sensor networks WSNs location information plays an important role in many fundamental services which includes geographic routing target tracking location-based coverage topology control and others. One promising approach in sensor network localization is the determination of location based on hop counts. A critical priori of this approach that directly influences the accuracy of location estimation is the hop-distance relationship. However most of the related works on the hop-distance relationship assume the unit-disk graph UDG model that is unrealistic in a practical scenario. In this paper we formulate the hop-distance relationship for quasi-UDG model in WSNs where sensor nodes are randomly and independently deployed in a circular region based on a Poisson point process. Different from the UDG model quasi-UDG model has the non-uniformity property for connectivity. We derive an approximated recursive expression for the probability of the hop count with a given geographic distance. The border effect and dependence problem are also taken into consideration. Furthermore we give the expressions describing the distribution of distance with known hop counts for inner nodes and those suffered from the border effect where we discover the insignificance of the border effect. The analytical results are validated by simulations showing the accuracy of the employed approximation. Besides we demonstrate the localization application of the formulated relationship and show the accuracy improvement in the WSN localization. 1 Introduction In recent years wireless sensor .