1 research outputs found
Hierarchical and Nonhierarchical Three-Dimensional Underwater Wireless Sensor Networks
In some underwater sensor networks, sensor nodes may be deployed at various
depths of an ocean making those networks three-dimensional (3D). While most
terrestrial sensor networks can usually be modeled as two dimensional (2D)
networks, these underwater sensor networks must be modeled as 3D networks. This
leads to new research challenges in the area of network architecture and
topology. In this paper, we present two different network architectures for 3D
underwater sensor networks. The first one is a hierarchical architecture that
uses a relatively small number of robust backbone nodes to create the network
where a large number of inexpensive sensors communicate with their nearest
backbone nodes, and packets from a backbone node to the sink is routed through
other backbone nodes. This hierarchical approach allows creating a network of
smaller number of expensive backbone nodes while keeping the mobile sensors
simple and inexpensive. Along with network topology, we also study energy
efficiency and frequency reuse issues for such 3D networks. The second approach
is a nonhierarchical architecture which assumes that all nodes are identical
and randomly deployed. It partitions the whole 3D network space into identical
cells and keeps one node active in each cell such that sensing coverage and
connectivity are maintained while limiting the energy consumed. We also study
closeness to optimality of our proposed scheme