Channel assignment and spatial reuse scheduling to improve throughput and enhance fairness in wireless mesh networks

Abstract

In wireless mesh network, by equipped mesh router with multiple radios tuned into orthogonal channels, throughput improvement problem can be alleviated. Efficient channel assignment and link scheduling is essential for throughput improvement. Effective channel assignment schemes can greatly relieve the interference effect between nearby transmissions. However, not only the links in wireless mesh network using different channels can be activated at a time, but some links in the same channel also can be activated concurrently if the SNIR (Signal-to-Noise and Interference Ratio) at their receiver endpoints is not lower than the threshold. In this paper, we investigate the problem of how to schedule a set of feasible transmission under physical interference model by using the Spatial TDMA access scheme and channel assignment in wireless mesh networks. We also consider the fairness enhancement to prevent some border nodes of the network from starvation. By using Minimum Spanning Tree as network subgraph constructed from original network graph, we propose centralized algorithms for scheduling and channel assignment to maximize the aggregate throughput and to provide the fairness of the network. We also evaluate the throughput improvement and fairness enhancement of our algorithms through extensive simulations and the results show that our algorithm can achieve significant aggregate throughput and fairness performance. © Springer-Verlag Berlin Heidelberg 2007.