Cooperative bargaining solution for efficient and fair spectrum management in cognitive wireless networks

This paper studies the fairness among the primary users (PUs) and the secondary users (SUs) for resource allocation in cognitive radio systems. We propose a novel co-opetition strategy based on the Kalai- Smorodinsky bargaining solution to balance the system efficiency and the fairness among users. The strategy formulates the spectrum sharing problem as a nonlinear and integral sum utility maximization subject to a set of constraints describing the co-opetition among the PUs and the SUs. Then, we solve the maximization problem by proposing a heuristical method that consists of four steps: multi-PU competition, PU's subcarrier contribution, multi-SU competition, and SU's subcarrier contribution. Extensive simulation results are presented by comparing the co-opetition strategy with several conventional ones, including the Kalai- Smorodinsky bargaining solution, sum rate maximization as well as the Max-Min. Results indicate that the co-opetition strategy can jointly balance the system efficiency and fairness in multiuser resource allocation, as it is able to support more satisfied users and in the meanwhile improve the utility of those unsatisfied. Moreover, the co-opetition can help enable the coexistence of the PUs and the SUs in cognitive radio systems.