An Improved Unequal Cluster-Based Routing Protocol for Energy Efficient Wireless Sensor Networks

Wireless sensor networks (WSNs) have been increasingly interested by industry and academic cycles for their potential use in applications such as environmental monitoring and military surveillance and so on. The paper considers the energy constraints of clustered WSNs and proposes an improved routing protocol for such WSNs to achieve a global optimization in energy consumption for all cluster head nodes, which reduce the effects of hot spots in some nodes near the sink node and prevent the hot head nodes to be overloaded for data communication. In such a routing protocol, a time-oriented competition algorithm is used to select cluster head nodes for a running WSN to reduce the dynamic topology of broadcast message among sensor nodes instead of negotiation mechanism, which is aimed at reducing network traffic burdens. Furthermore the distance between nodes and the sink node as a campaign index are taken into account to decline the unequal power distribution of clusters' nodes in WSNs supervise by the protocols, which help to uniform consuming energy of all nodes in a WSN to some extent. The nodes in a cluster decides their head node by considering the distance between their communication position and candidate cluster head nodes, for which the proposed protocol guarantees a rational size of the cluster. The novel protocol algorithm is tested by a Matlab simulation program. Compared with the conventional LEACH (Low-Energy Adaptive Clustering Hierarchy) algorithm and EEUC (Energy-Efficient unequal Clustering) algorithm, the simulation results show that the improved routing protocol is more stable to reduce the whole energy consumption of a WSN with more balanced communication loads and extends the networks' life time.