Regional Clustering Scheme in Densely Deployed Wireless Sensor Networks for Weather Monitoring Systems

Clustering protocol that is used in wireless sensor network is an efficient method that extends the lifetime of the entire network. However, when this method is applied to an environment in which collected data of the sensor node easily overlap, sensor nodes unnecessarily consumes so much energy. In the case of clustering technique that use a threshold, the lifetime of the network is extended but the degree of accuracy of collected data is low. Therefore it is hard to trust the data and improvement is needed. In addition, it is hard for the clustering protocol that uses multi-hop transmission to normally collect data because the selection of a cluster head node occurs at random and therefore the link of nodes is often disconnected. Considering the whole networks, nodes nearer the sink have to take heavier traffic load. Therefore, nodes around the sink would deplete their energy faster, leading to what is called an energy hole around the sink. Accordingly this paper suggested a cluster-formation algorithm that reduces unnecessary energy consumption and that works with an alleviated link disconnection. According to the result of performance analysis that used environment data, the suggested method lets the nodes consume less energy than the existing clustering method and the transmission efficiency is increased and the entire lifetime is prolonged by about 30%.