presentation by: drew wichmann paper by: samer hanoun and saeid nahavandi 1
TRANSCRIPT
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Dynamic Route Construction for Mobile Collectors in Wireless Sensor NetworksPresentation by: Drew WichmannPaper by: Samer Hanoun and Saeid Nahavandi
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Wireless Sensor Networks (WSNs)
Set of small nodesDistributed in spaceMonitor conditionsBuilt with
Transceiver Microcontroller Sensor Energy source
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Power Consumption
Biggest Issue
Forwarding
Bottlenecking Unbalanced distribution
Solution Mobile Sinks
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Mobile Sinks
Mechanical data carrier Robot Unmanned Aerial Vehicle (UAV)
Physically approach sensorsRequires routes
Random Static Dynamic
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Problem Formulation
Assumptions Known locations Sensor nodes stationary Uniformly distributed Sleep when full Mobile collector▪ Sufficient energy▪ Sufficient memory
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Problem Formulation (Continued)
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Route Construction Algorithm
1. Build a fully connected graph G(V,E) of all sleeping sensors
2. Select a vertex r (center of sensing field) to be a root vertex
3. Compute a minimum spanning tree T for G from root r
4. Let L be the list of vertices visited in a DFS on T
5. Generate the Hamiltonian cycle H that visits the vertices in the order L
6. Follow the Hamiltonian cycle H as the constructed route
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Example
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Build connected graph
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Select root
Root r
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Compute Minimum Spanning Tree
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Create List
ABFGCDE
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Find Hamiltonian Cycle
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Follow Hamiltonian Cycle
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Simulation
Parameters 150 Sensors (uniformly distributed)
100m x 100m area
1 KB buffer
50000 time units
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Simulation Parameters (continued)
Events occur at centerRi = i * R1
R1 = 10msensingrangei =
[ baserate * (i-1) + 1, baserate * i ]
baserate = 2 seconds
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Results
20 different independent networksCompared with closest neighborMetrics
Sleeping Time Number of Sleeping Sensors Sleeping Time per Request Distance Travelled per Request
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Results
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Results
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Conclusion
No dependency on data generation rates
Minimize sleeping times
Better performance than closest neighbor
Shows effect of speed and number of collectors
Future work Cooperation between collectors Real-time requests