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Efficient Sensor Node Deployment Schemes for AOFSN. Limei Peng , Nov. 1, 2010 Korea Advanced Institute of Science and Technology(KAIST), South Korea. Outlines. Abstract Preliminary Works Sensor Node Deployment Schemes Results Conclusions. Abstract. Abstract.
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Efficient Sensor Node Deployment Schemes for AOFSN LimeiPeng, Nov. 1, 2010 Korea Advanced Institute of Science and Technology(KAIST), South Korea
Outlines • Abstract • Preliminary Works • Sensor Node Deployment Schemes • Results • Conclusions
Abstract • Wireless Sensor Networks (WSN) • Weak immunity to electromagnetic interference • Short life time due to lack of power • Bad reliability • All-Optical Fiber Sensor Networks (AOFSN) • Immune to electromagnetic interference • Harsh to hostile environment • Power-efficiency/Passive devices • Long life-time • Can be applied into environment monitoring, home caring or structural monitoring
Motivation & Objective • Motivation • Large-scale based AOFSN can be applied to structural/environment monitoring, home caring, e.g., mansions, bridges, forest, etc. • Objective • This kind of large-scale AOFSN should be optimized in terms of: • High reliability & sensing accuracy • Cost Efficiency
Fiber sensor networks • Reliability • Topologies • Hierarchical/regular topologies with high recoverability/self-healing, such as star-bus-ring • High recoverable switches • Sensing Accuracy • Sensor node deployment or Coverage problem • Full Coverage • Optimal Partial Coverage
Reliability-topologies • Hierarchical AOFSN Architectures • Three levels: • 1st: Interrogation/Server (InS) • 2nd: Remote Node (RN) • 3rd: Sensor Sub-Network (SSN) • Three hierarchical types: • 1st type (Figure 1) • 2nd type(Figure 2) • 3rd type(Figure 3)
Reliability-topologies Figure 2 2nd type AOFSN Figure 1 1st type AOFSN Figure 3 3rd type AOFSN
Reliability/Recoverability • Reliability in the 3rd SSN level • Square-based deployment & switch architecture Figure 4 Recovery process when two link failures happen simultaneously
Accuracy-Node deployment • Efficient node deployment schemes • High sensing accuracy • Good coverage ability, low blinding ratio • Low cost • Low overlapping ratio • High reliability • Good self-healing topology • Inspiring us coming with the close-packing concept..
Accuracy-Node Deployment • Close-packing in Two-dimensional (2-D) & Three-dimensional (3-D) Figure 5 Kissing…coins. In this two-dimensional example of packing, each coin is surrounded by six others. In fact, this is the closest packing arrangement possible, and defines the “kissing number” for two dimentions. Figure 6 Orange arrangement. Greengrocers do it instinctively, but mathematically it is proven that the closest packing in three dimensions is achieved with a kissing number of 12: each orange enclosed inside this stack is in contact with 12 neighbors.
Node Deployment Schemes • Two-Dimension • 2-D Close-Packing Sensor node Deployment(2-D CPSD) • 2-D Closest-Packing Sensor node Deployment(2-D CestPSD) • Figure 7. 2-D CPSD • Figure 8. 2-D CestPSD
Node Deployment Scheme • Three-Dimension • 3-D Closest-Packing Sensor node Deployment(3-D CestPSD) • Figure 9. HCP (Hexagonal Close Packed Structure)
Node Deployment Schemes • Figure 10. a) layer A; b) layer B • Figure 11. a) 3-D CestPSD based HCP: ABABA; • b) Sensor node deployment in AOFSN
Metrics • Definition of Metrics • Coverage (C): The sensing area of AOFSN • Coverage Ratio (CR): Given a coverage area, the area ratio how AOFSN can cover using a node deployment scheme • Blinding Ratio (BR): Given a coverage area, the ratio that AOFSN cannot cover using a node deployment scheme. • Overlapping Ratio (OR): The ratio of the sensing area that is covered by more than one sensor nodes. • Node Density (ND): Given the coverage requirements, the number of sensor nodes that are needed to satisfy the requirement.
Efficient Sensor Node Deployment has been proposed • Optimal partial coverage • Mathematical Closest packing based methods in both two-dimensional and three-dimensional spaces. • Showed to have the optimal coverage ratio considering no overlapping ratio and low node density.