Spectrum Allocation for Distributed Throughput Maximization under Secondary Interference Constraints in Wireless Mesh Networks

Secondary interference constraints are important, because of representing the transmission constraints of the widespread and promising IEEE 802.11 wireless technology. Under secondary interference constraints, distributed link scheduling algorithms for multihop wireless networks can only achieve a fraction of the maximum possible throughput in general, but distributed Greedy Maximal Scheduling (GMS) algorithms can achieve optimal throughput in some network graph structures. It is possibly helpful for the improvement of distributed throughput to partition a network into subnetworks such that the subnetwork assigned to each frequency channel achieves distributed throughput maximization. In this paper, we investigate the structure characteristics of the subnetwork in which GMS achieves optimal throughput under secondary-interference constraints, and define a type of network subgraph structures meeting the requirement - special chordal subgraphs. Based on this, we propose a channel assignment algorithm, including a network partitioning algorithm and a topology balancing algorithm. By simulation, we evaluate the achievable throughput and fairness in a distributed matter using our algorithm, in comparison with the existing Max K-cut based channel assignment algorithm.