Enhancing data delivery with density controlled clustering in wireless sensor networks

Wireless sensor networks (WSN) are primarily used for sensing and collecting the information from environment. This information is sent to base station (BS), where, it is processed and analyzed by the underlying application. Functioning of WSN highly depend on the deployment strategy and the coordination among the sensor nodes. Preserving the energy is an important goal that must be considered when developing a routing protocol for WSNs. Radio communication in sensor nodes is highly expensive operation in terms of energy usage. Energy can be conserved in an efficient way with specifically customized routing techniques. Data aggregation methods when applied to sensor nodes, clusters are created where data generated from cluster members is aggregated. This kind of data collection strategy results into energy efficient communication. Integration of data aggregation and clustering approach is enabled through customized hierarchical routing strategies. Clustering technique is key to apply and exploit, the advantages in-network data processing offers. This paper compares various clustering protocols like LEACHC, K-means and its variants. The protocols are compared with respect to network lifetime, data delivery and energy consumption. These protocols only consider intra cluster distance of members while doing clustering, due to this non-uniform clusters are created. These kind of clusters do not deliver data periodically and uniformly from every corner of the field. A density control based approach is proposed which does balancing of cluster members assignment in a loose way. A loose density control (LDC) based approach is integrated with K-means clustering method. LDC based approach exhibits improved average data delivery per node, ensuring regular data availability from every corner of the deployment area as long as the nodes are alive. Not only it improves the amount of data delivered, it also improves the network lifetime considerably. This performance improvement is achieved with almost similar energy expenditure compared to other protocols.