An Improved Opportunistic Routing Protocol for Underwater Wireless Sensor Networks

Underwater wireless sensor networks (UWSNs) is an effective system to support real-time and continuous data transmission, and much attention has been drawn to routing protocol for UWSNs. However, unreliable communication between nodes is the most challenging for successful data transmission in UWSNs under the complicated underwater environment. Therefore, in order to enhance the stability of data transmission, a credit-based opportunistic routing (COR) protocol is proposed. The value of credit, which is calculated by link quality and distance vector according to their respective weights, is an index used to construct Next-hop forwarding candidate nodes (NFCNs). Subsequently, in order to speed up data transmission, a time allocation strategy is used to configure the waiting time for nodes with different priorities. The simulation results demonstrate that the proposed protocol can enhance the stability of data transmission and reduce the transmission delay.