Fast Data Collection Protocol Design for Underwater Wireless Sensor Networks

The high latency of acoustic transmission in an Underwater Wireless Sensor Network (UWSN) allows multiple transmitters at different distances from the receiver to send concurrently. The high latency feature has been used in many existing MAC protocols to reduce data collection time. How-ever, most of data collection protocols adopt contention-based mechanisms and suffer from transmission collisions when the number of nodes increases. In this paper, a Contention-Free Pipelined Scheduling (CFPS) is proposed to reduce the time for data collection. The core idea of CFPS is to partition nodes into sub-clusters and then design a contention-free transmission scheduling table for different sub-cluster heads. It is expected that the CFPS protocol can reduce data collection time and improve network throughput when compared to the three well-designed data collection protocols, namely DAP-MAC, RHNE-MAC, and NF-TDMA.