Throughput-optimal configuration of fixed wireless networks

Abstract—In this paper, we address the following two questions concerning the capacity and configuration of fixed wireless net-works: (i) given a set of wireless nodes with arbitrary but fixed locations, and a set of data flows, what is the max–min achiev-able throughput? and (ii) how should the network be configured to achieve the optimum? We consider these questions from a net-working standpoint assuming point-to-point links, and employ a rigorous physical layer model to model conflict relationships be-tween them. Since we seek capacity results, we assume that the network is operated using an appropriate schedule of conflict-free link activations. We develop and investigate a novel optimization framework to determine the optimal throughput and configura-tion, i.e., flow routes, link activation schedules and physical layer parameters. Determining the optimal throughput is a computa-tionally hard problem, in general. However, using a smart enumer-ative technique we obtain numerical results for several different scenarios of interest. We obtain several important insights into the structure of the optimal routes, schedules and physical layer pa-rameters. Besides determining the achievable throughput, we be-lieve that our optimization-based framework can also be used as a tool, for configuring scheduled wireless networks, such as those based on IEEE 802.16. Index Terms—Capacity, fixed wireless networks, IEEE 802.16, mesh networks, optimal scheduling and routing. I