Topology control for balanced energy consumption in emergency wireless deployments

• Authors: Alaa A. Abdallah;Mohammed Hassan;George S.-C. Kao;Calin D. Morosan
• Venue: PE-WASUN '05 Proceedings of the 2nd ACM international workshop on Performance evaluation of wireless ad hoc, sensor, and ubiquitous networks
• Year: 2005

Wireless networks became an integral component of nowadays communication infrastructure and, due to their mobility and limited battery life, energy efficiency needs an important design consideration. Such networks are usually modeled by so called mobile ad-hoc networks (MANETs) models, further represented as simple graphs where the vertices have precise geometric locations and edges are straight lines.Topology control is concerned with the assignment of different transmission power to wireless devices antenna such that the obtained ad-hoc networks satisfy some specific properties (connectivity, planarity, minimum energy, bounded degree, etc.). In this paper, we study the energy-balanced topology control problem, which is defined as follows: given a set of hosts in an ad hoc network, adjust the transmission power of each host so that the resultant network topology is connected and the maximum energy consumption among all the hosts is minimized. This problem has been solved by Ramanathan et. all [12] for static ad-hoc networks in a 2D environment.We extend the algorithm from [12] for a dynamic environment in both 2D and 3D environment. We describe a communication protocol on top of this algorithm in order to ensure the connectivity and the energy balanced properties.During the movement of nodes, the topology has to be changed. Since, in our protocol, each reconfiguration implies that all the nodes will transmit at maximum power, we study the influence of increasing the transmission radius of each node, by a fixed percent, over the number of reconfiguration needed, in order to maintain the network connectivity. Using an original network simulator, we show that the decreasing in the number of reconfigurations is exponential in terms of percentage of transmission radius increasing, which leads to a trade-off between the energy consumptions due to reconfigurations and due to the increased transmission radius. We also study the implication of other factors over the number of reconfigurations, such as node density, maximum transmission range, and different movement parameters (speed, changing of direction time).