An Energy Efficient Cluster-Head Rotation and Relay Node Selection Scheme for Farmland Heterogeneous Wireless Sensor Networks

A new routing protocol of wireless sensor network is proposed in this paper. Node residual energy, network topology density and the distance to the sink are all under consideration in the cluster-head election, which could improve the network energy efficiency while doing the power consumption equalization. An energy threshold of cluster-head is applied to reduce the frequency of cluster-head rotation. A relay node selection scheme is used to satisfy the network connectivity in large-scale farmland application and lower the power consumption of far-end cluster-heads. Through extensive performance evaluation, results show that the 10% nodes-die network lifespan of ECRRS (energy efficient cluster-head rotation and relay node selection) is about 1.3 times of HEED (hybrid energy efficient distributed), 2.1 times of CHCS (cluster-head cycling switch) and 4.5 times of LEACH (low energy adaptive clustering hierarchy). The cluster-head selection cost of ECRRS is about 38% of HEED and 33% of CHCS. The energy balance performance of ECRRS is a little better than CHCS and much better than LEACH. The energy efficiency of farmland WSN is improved by using ECRRS.