An energy efficiency semi-static routing algorithm for WSNs based on HAC clustering method

In Wireless Sensor Networks (WSNs), energy efficiency is one of the most important factors influencing the networks' performance. Through a well designed routing algorithm, WSNs' energy efficiency can be improved evidently. Among various routing algorithms, hierarchical routing algorithms have advantages in improving nets' robustness and flexibility, and it is more appropriate for large scale of networks. In this paper, some typical hierarchical routing algorithms are introduced, and their advantages and defects are analyzed. Based on these analyses, a new hierarchical routing algorithm with high energy efficiency named EESSC is proposed which is based on the improved HAC clustering approach. In EESSC, the sensor nodes' residual energy would be taken into account in clustering operation, and a special packet head is defined to help update nodes' energy information when transmitting message among the nodes. When the clusters have been formed, the nodes in cluster would be arrayed in a list and cluster head would be rotated automatically by the order of list. And a re-cluster mechanism is designed to dynamic adjust the result of clustering to make sensor nodes organization more reasonable. At last, EESSC is compared to other typical hierarchical routing algorithms in a series of experiments, and the experiments' result which proves that EESSC has obviously improved the WSNs' energy efficiency has been analyzed.