An Improved Equal Hierarchical Cluster-Based Routing Protocol for EH-WSNs to Enhance Balanced Utilization of Harvested Energy

Enhancing harvested energy utilization and balancing harvested energy consumption are the main challenges in designing routing protocols for energy harvesting wireless sensor networks (EH-WSNs). This paper considers the efficient hierarchical cluster-based routing method for enhancing harvested energy utilization while ensuring harvested energy consumption balancing, reliability and connectivity of EH-WSNs. For these aims, a new hierarchical cluster-based routing protocol for EH-WSNs is proposed. This protocol contains two phases: cluster-route establishment and data transmission. Cluster-route establishment phase including CH selection, next-hop CH selection and joining CMs to a proper CH, is performed using multi-criteria such as residual energy, distance to the BS, node adjacency degree, link statistics and energy harvesting rate of nodes. Moreover, modified sensing radius adjustment scheme is introduced to further improve energy consumption balance of each node from sensing time. In data transmission phase, an adaptive transmission power adjustment scheme is proposed to use more effectively harvested energy considering current residual energy and predicted energy harvested from ambient environment. This phase further improves energy consumption balance by using a mobile sink. Extensive simulations are conducted to demonstrate that the proposed protocol achieves better network performance than the other existing protocols for EH-WSNs.