Data Gathering Method In Ring-shaped Wireless Sensor Networks

Wireless Sensor Networks (WSNs) is a system which is application-related anddata-centric. Network applications are based on effective data collection. Because ofthe limitations of sensors’ hardware and its application environment, energy-efficienctprotocol plays an important role in WSNs’ data collection. The method ofmany-to-one data stream of data collection often leads to high energy consumption oflocal area network，forming the energy holes problem. The energy holes problemmakes a grave waste of network energy and greatly reduces the network lifetime.Ring-shaped network model is a common applied model by the existing WSNs’ datacollection. Therefore, this paper focused on effectively prolonging network lifetimeand achieving energy balance for ring-shaped network. The main work and innovationare as follows:Firstly, the energy consumption and network lifetime are studied in ring-shapedperiodical data gathering networks. The result shows that the network lifetime equalsto the service time of the node inside the ring that is nearest to the sink node. Thenetworks’ lifetime is up to the width of the nearest ring to sink.Secondly, a data collecting cluster algorithm is proposed depending on thering-shaped data collection network. The number of clusters and the competitivepercentage of cluster heads in each ring can be identified according to the theoreticalanalysis results. The algorithm for cluster head making data fusion and transmission isproposed, which prolongs the network’s service time balancing the energyconsumption of inner ring nodes at the cost of energy consumption in clustertransmission of the outer ring nodes. The simulation results show that the lifetimewith the cluster algorithm is relative with the number of clusters in each ring and thedata fusion ratio. The algorithm can improved the network lifetime nearly by67%inuniformed networks. Considering the application, a simple algorithm of sector clustermethod and timing cycle is proposed in the paper.Thirdly, this thesis applies the cluster algorithm to irregular area network, whichis divided into many sectors. The cluster algorithm can also achieve energy balance inthe irregular networks.