Enhanced Self-Organization Clustering in Mobile Wireless Sensor Networks

When the sensor field is too large in self-organization clustering, energy inefficiency may result when cluster-heads broadcast an Advertisement Message over the sensor field area. Limiting the transmission range of the Advertisement Message is a requirement in this case. Detrimentally, when the transmission range is limited, Advertisement Message non-receiving nodes can be generated due to self-organization clustering. In this paper, we analyze the number of non-receiving nodes in relation to the transmission range when selforganization clustering protocols are used in mobile environments and propose a Two-Tier Clustering method. Two-Tier Clustering evenly distributes clusterhead nodes over the network field and prevents any cluster-head clumping generated by self-organization clustering. Accordingly, our Two-Tier Clustering Method can reduce the number of non-receiving nodes that result when the transmission range is controlled.