Efficient localized topology control for wireless ad hoc networks.

摘要

While many fundamental ideas existed about twenty to thirty years ago, recent years we see tremendous research activity in wireless ad hoc networks due to its applications in various situations such as battlefield, emergency relief, and so on. Mobile wireless networking enjoys a great advantage over the wired networking counterpart because it can be formed in a spontaneous way for various applications. There are no wired infrastructures or cellular networks in wireless ad hoc network. Each mobile node has an adjustable transmission range. The nodes within each other's transmission ranges can communicate directly. Otherwise, two nodes have to communicate through multi-hop ad hoc wireless links by using intermediate nodes to relay the message.; In this thesis, I focus on discussing one of the central challenges in the design of wireless ad hoc networks: efficient localized topology control. I study how to construct a sparse spanner efficiently as the network topology for a set of static or quasi-static wireless nodes such that, for any given pair of nodes, there is a power-efficient path. I first review previous results for topology control when the network is modeled by unit disk graph. Then, I propose several new localized structures: some bounded degree structures (Chapter 3), one planar spanner (Chapter 4), and one planar spanner with bounded degree (Chapter 5). All of these new topologies can be constructed efficiently and dynamically in wireless ad hoc networks. Moreover, they have some nice properties in improving the performance of the networks. Finally, I also show some simulation results and discuss the possible future works as a conclusion of this thesis.