A Depth-Distance Based Energy-Efficient and Energy-Balanced Routing Protocol for Underwater Wireless Sensor Networks

Abstract

Underwater Wireless Sensor Networks (UWSNs) are pivotal for ocean monitoring, exploration, and surveillance, comprising sensor nodes with limited battery capacity that rely on acoustic communication and are deployed at the seabed, making battery recharging impractical. Despite the challenges in underwater communication, numerous routing protocols (RPs), such as Energy Balanced Efficient and Reliable Routing (EBER²) and Shifted Energy Efficiency and Priority (SHEEP), have been developed to optimise forwarding node selection and improve communication efficiency by incorporating parameters such as depth information (DI), transmission distance (TD), and residual energy (RE). However, designing energy-efficient (EE) and energy-balanced (EB) RPs for large-scale UWSNs remains an NP-hard problem due to the network's inherent complexity. This study introduces a Depth-Distance-based Energy-Efficient and Energy-Balanced (DDE²) routing protocol, which optimises energy consumption using TD, DI, RE, and additional parameters such as transmission range (TR). The DDE² protocol extends network lifetime while meeting critical quality-of-service (QoS) requirements, including scalability and low latency, and outperforms recent state-of-the-art RPs in energy efficiency, network longevity, and overall QoS for UWSNs.