An Adaptive MAC Protocol for Energy Harvesting Wireless Sensor Networks in Harsh Environment

Research on Energy Harvesting Wireless Sensor Networks (EH-WSN) has received much attention in recent years. However, in practical applications, due to the forced movement of sensor nodes in the deployment environment or the randomness of deployment, the dense and sparse distribution areas of nodes are formed in the monitoring area, and there may also exist isolated nodes. In the dense region, data conflicts are easily generated between nodes, while in the sparse region, the connectivity between nodes is low, the packet loss rate becomes high, and the data of isolated nodes cannot be transmitted normally. To address the above problems, this study proposes an adaptive MAC protocol in EH-WSN in harsh environments. This paper proposes an adaptive MAC protocol for EH-WSN in harsh environments, (AHE-MAC). The main idea of AHE-MAC is that: for the uneven distribution of nodes in harsh environments, this research firstly categorizes the node deployment area into “dense area and sparse area”. Secondly, different data transmission methods are proposed for different regions; in the dense region, the nodes implement the dynamic sleep mechanism, which puts some nodes to sleep and other nodes transmit the data to the next hop nodes, thus reducing the data transmission conflicts. In the sparse region, the isolated nodes adopt the “tentative power increasing“ mechanism to transmit data packets, and the other sparse nodes adopt the improved TDMA algorithm to transmit data, thus increasing the connectivity of the nodes. The simulation results prove that the protocol ensures the effective transmission of data in different network areas and improves the network performance at the same time.