Energy-Efficient Data Collection Scheme Based on Value of Information in Underwater Acoustic Sensor Networks

In recent years, underwater acoustic sensor networks (UASNs) have played an increasingly important role in ocean exploration. However, underwater sensor networks suffer from severe propagation attenuation, limited energy, and sensor mobility compared with terrestrial networks. Also, the value of sensing data is quite different in some applications of underwater data collection. To tackle these challenges, this article proposes a hierarchical collection strategy based on Value of Information (VoI). Taking account of the mobility of nodes close to sea level, we divide the network into two layers according to the Ekman drift current model. In the upper layer, the nodes move violently with the sea water. We adopt opportunistic routing to allow these nodes to search for the appropriate next hop nodes actively. Meanwhile, nodes in the lower layer are clustered. According to the rarity of the data received in the historical data, we propose a novel mathematical formula to measure the VoI of the data, and define the ratio of received data value to energy consumption as the evaluation index of network energy efficiency. AUV-aided transmission and multihop transmission are utilized separately to determine the tradeoff between energy consumption and network performance. The choice of transmission mode depends on the VoI in a cluster. Simulation results indicate that the proposed strategy shows satisfactory performance in improving energy efficiency.