The Q1 authors present a distributed opportunistic channel acquisition mechanism in dynamic spectrum access (DSA) networks. A novel graph MAximum SPECTrum packing algorithm (MASPECT) is proposed for a system with N secondary networks, in which each secondary network makes use only of the local topology information (i.e. information about itself and its one-hop neighbours) to resolve contentions during channel access. The proposed algorithm also adapts easily to topological changes. Most approaches to channel acquisition use either centralised graph colouring approaches or distributed approaches that result in under utilisation of spectrum resources. The authors show that the proposed MASPECT algorithm results in improvements by up to one order of magnitude in the spectrum utilisation for the secondary networks and results in Jain's fairness index of about 0.9. The authors further present a modified probabilistic heuristic, PMASPECT, that improves the termination time of the algorithm by up to two orders of magnitude. To the best of the authors' knowledge this is the first heuristic proposed to reduce the termination time, that makes use of the relative degrees of a node and its one-hop neighbours. The authors also study the impact of the proposed MASPECT algorithm on each individual secondary network in the system in the presence of primary activity. For each secondary network, the proposed algorithm is observed to result in up to two orders of magnitude of reduction in the new call blocking and in the call dropping probabilities in the presence of primary activity.
An opportunistic distributed channel graph coloring algorithms for the spectrum access in dynamic spectrum access networks is presented in REF .
MAximum SPECTrum packing : a distributed opportunistic channel acquisition mechanism in dynamic spectrum access networks
Mathematics Computer Science