Design of sensor nodes in underwater sensor networks

Abstract

Since the mid of 1990s, terrestrial wireless sensor network is developing quickly. However, constrained by certain characteristics of underwater acoustic channel such as limited available bandwidth and large propagation delays, which means development of underwater sensor networks, the extension of the concept of terrestrial wireless sensor network in ocean application, lags behind that of terrestrial wireless sensor network. Besides, due to the fact that the underwater instruments are usually battery-powered, and the power consumption of single node is directly relevant to the life of entire network, the design of low power architecture of nodes and energy-efficient MAC protocol are the highlight in recent research. This paper proposed a design of underwater acoustic network node with low power consumption. By using the ‘Sleep/Wake’ operation mode, the average power dissipation of the node is reduced. And then based on software radio concept, the node project can achieve a better extent of application flexibility. A complete prototype has been tested in a anechoic pond, and the result shows the prototype has features of compact structure, reliable performance and low power consumption. Since the network node is the core section of underwater sensor networks, this design provides good platform for the research and verification of MAC layer of practical underwater sensor network.