Energy and Coverage Aware Routing Algorithm in Self Organized Sensor Networks

Jakob Salzmann

INSS 2007,07.06.2007, Braunschweig

Institute of Applied Microelectronics and

Computer Engineering University of

Rostock

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Outline

Motivation

Clustering

Routing

Conclusion & Outlook

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Motivation

Photo: Jason Hill, UCB

Cheaper and smaller, but more nodes

Main problem: energy consumption

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Dividing the network into clustersLess Communication

Hierarchical Structure

Clustering I

Clusterhead consumes more energy

Problem: Different position in a cluster Different transmission range

New Clusterheads have to check for connections Communication overhead

Our goal: Limits for clusters which allow unconditional role changes

Lifetime increase by role changing

Sensor node Sink Clusterhead

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Clustering II

Grid with quadratic cells

Max cell size restricted byTransmission rangeSensing range

Transmission Range RT Sensing Range RS

L

2

)2;min( TS RRL

L

L

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Clustering III

Sensor node

Sink

Clusterhead

Switched-off node

Estimation of the virtual

grid

Determining the

Clusterhead in each cell

Temporary switch-off

remaining nodes without

loss of performance

Emerging of clusters with

different lifetimes

Low populated Cluster

Well populated Cluster

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Scale Free Networks

US airline systemInternet

Network results from preferred connection

Many nodes with few connections, few nodes with many connections

Robust against random attacks

Our goal: Adoption of Scale free behavior to our developed

clustering algorithm

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Routing Algorithm

Sink Switched-off node Low populated Cluster

Well populated Cluster

Our approach:Starting with the sinkAfter attending the network, nodes connect with all unconnected nodes in range

Built up a network with scale free behavior

Optimizations:Range ReductionLimited ConnectivityWait and See

Well populated cluster become hubs

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Conclusion & Outlook

ResultsDeveloped a clustering algorithm

Unconditional role changingConsiders coverage and connectivity

Applied a routing algorithmScale free behaviorRobust against random failures

Future WorkImprovement of cell sizesStronger cross linking for improved robustness