Joint Effects of Void Region Size and Sink Architecture on Underwater WSNs Lifetime

Underwater wireless sensor networks (UWSNs) typically suffer from the communication void region problem. A common method to handle the void region problem is to reroute the packets around the void regions. As the size of the void regions increases, packets require more hops to circumvent the large void regions, resulting in a short network lifetime. On the other hand, the void region problem is more destructive in UWSNs utilizing a single-sink architecture than a multisink architecture since nodes consume excessive energy for bypassing the void regions to reach the sink node, which can be positioned in a hard-to-reach area in single-sink UWSNs. In this work, an integer linear programming (ILP) model is developed for maximizing UWSNs lifetime while bypassing the void regions. Solving the ILP model to optimality, the joint impact of the void region size and the sink architecture type on UWSNs lifetime are investigated. The results show that the performance of UWSNs significantly drops as the size of the void region grows such that UWSNs lifetimes shorten by up to 61% as the total void region size is one-quarter of the network size. Moreover, multisink UWSNs yield better performance than single-sink UWSNs in the void region problem.