Abstract

Abstract — We consider the uplink channel assignment problem in a multi-channel access point wireless network, with the goal of attaining maximum system throughput. In this setup, a set of orthogonal channels must be assigned to a set of users, where each user splits its power optimally across the channels allocated to it. While the optimal power allocation solution has a “water-filling” type structure, the optimal channel assignment problem is very challenging due to the non-linear dependence of user throughput on the set of channels assigned to it. Since the optimal channel allocations is computationally intensive to obtain in general, we analyze the system in the two extremal SINR regimes (very high and very low SINR) and show how the optimal solutions can be obtained in these regimes in a computationally efficient manner. Finally, we demonstrate that the best of the optimal solutions obtained for the two extremes show excellent (close to optimal) performance over the entire SINR range. develop solutions that are computationally efficient, practical, and result in a performance that is close to optimal. The paper is structured as follows. In Section II, we discuss the related work in this space and their relationship with our work. Section III describes the assumptions made in our study of the problem and the resulting optimization problem formulation. In Sections IV and V, we analyze the system throughput in extremal SINR regimes. This analysis motivates the development of algorithms that perform excellently in that they achieve close to the optimal system throughput. Detailed simulation results are presented in Section VI which compare the performance of the proposed algorithms to the optimal solution and intuitive greedy heuristics. I.

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