Towards energy efficient duty cycling in underwater wireless sensor networks

Underwater Wireless Sensor Networks devices are usually battery powered and thereby their lifetime is limited. This issue leads to lose data measurements and thus to a performance loss of the underlying UWSN application. It also increases the maintenance cost in Internet of Underwater Things scenarios with a huge number of UWSN devices. Additionally, the unique characteristics of UWSNs pose several constraints such as the high energy consumption, long propagation delay, and node mobility. Duty Cycle management is one of the key technologies to solve this issue. In this context, the use of duty cycle based algorithms for opportunistic, autonomous and energy efficient duty cycle management can mitigate the undesirable impact of underwater communications, consequently, improve the overall efficiency of the algorithms designed for the UWSNs. In this article, we study the energy efficient data collection for asynchronous duty cycle MAC protocols for underwater sensor networks. To this end, we improve two previously proposed receiver initiated MAC protocols that use a nodes, (1) residual energy, and (2) its sleep-awake pattern to improve the overall network lifetime. We show that the considerations made in the protocols have a great impact on the performance of the network. Our results show that the protocols minimize the collisions while alleviating the need for excessive handshake and also the average active time of a node is minimized.