Energy-efficient routing protocol in underwater acoustic sensor networks

As the importance of applications, such as ocean sampling, environmental monitoring, disaster prevention, and distribution tactical surveillance, has recently grown, the need for underwater communication has become more pronounced. In order to perform underwater communication effectively for these applications, there are some major impediments which must be overcome in routing protocols, viz. the: 1) underwater channel characteristics including the usage of acoustic waves and long propagation times; 2) severe power limitations imposed by the reliance on battery power. To overcome these obstacles, we propose an energy-efficient, delay-decreasing routing protocol that uses energy-aware data aggregation. This mechanism reconfigures the aggregation tree via a dynamic pruning and grafting function to operate a temporal path from the uw-sources to the uw-sink. The proposed protocol is shown to achieve performance improvements: the energy saving is achieved by minimizing the number of data transmissions, the decrease in the delay is attained through the automatic movement of the aggregation point, and the lifetime extension of underwater sensor networks is also accomplished. In the simulation experiments, we evaluate these performance improvements.¹