Development of an improved neighboring-based energy-efficient routing protocol for underwater wireless sensor networks

Abstract

Underwater Wireless Sensor Networks (UWSNs) consist of sensor nodes deployed underwater to monitor and collect data on aquatic environments, essential for applications like military surveillance, oil & gas exploration and environmental monitoring. This research tackles the challenges of energy constraint and reliability of data transmission in UWSNs, which face issues such as variable channel conditions, significant signal attenuation, and limited bandwidth due to water currents and temperature variations. The Neighboring-Based Energy-Efficient Routing (NBEER) protocol is one of the techniques that was developed, which utilized a Neighbor Head Nodes (NHNs) selection strategy by considering nodes with high residual energy to collect data from other sensor nodes and sent it to the sink nodes on the water surface which aggregate the data and send it to the base station (BS) offshore, but the protocol do not consider the unpredictable conditions found in aquatic settings such as water currents and temperature variations during the selection of NHNs, resulted to inefficient energy utilization and diminishing network performance. To address this, a Dynamic Neighbor Adaptation (DNA) scheme was developed and integrated into NBEER, allowing the protocol to dynamically select Neighbor Head Nodes (NHNs) based on network conditions, energy level, water current, and temperature variation also, to re-cluster the displaced nodes to the nearest NHN after changes of water currents or temperature variation of the underwater environment. This adaptation improves load balancing and network stability. The proposed technique was simulated using MATLAB R2023b, the improved NBEER protocol achieved a reduced end-to-end delay of 47.55s, lower total energy consumption of 9.16J, a higher packet delivery ratio of 85.67% as performance metrics compared with 53.00s, 12.60J, and 78.80%, respectively as reported in literature. These results indicate improved network stability, more efficient energy utilization, reduced packet loss and prolonged network lifespan of the UWSNs.