Energy efficient topology for Wireless Mesh Networks

Abstract

Wireless Mesh networks employing the IEEE 802.11 a/b/g standard operate in the unlicensed frequency band. Their deployment has seen a tremendous growth since their introduction particularly for providing community based connectivity services. A number of wireless access points are deployed to provide these connectivity requirements. Due to this controlling the transmit power by the access points has become necessary as it is required to reduce interference and cost of operation and enhance performance. In this paper we study the problem of transmit power control by the access points in a wireless mesh network using computational geometry and coalition formation game theoretic framework from economics. We consider a typical wireless mesh network topology where mesh nodes are placed on the vertices of a two-dimensional lattice. We analyze the power control problem using coalition formation game theory employing utilities based on the coverage areas of the access points by associating a cost function with the utility as the payoff of the coalition members. Our work focuses on the access layer of a wireless mesh local area network. We show that by forming a coalition with fair allocation of payoffs among the members and assigning different radio ranges and coverage areas to the access points, a significant amount of transmit power can be saved while covering the required service area of the network.

Keywords: coalitional game theory, wireless mesh network, power control, core, utility, payoff, Voronoi diagram