Distributed spectrum-sharing in cognitive ad hoc networks using evolutionary game theory

摘要

As smart portable devices becoming increasingly popular and autonomous, the critical problem of spectrum congestion and inefficiency have drawn people' attention. Cognitive radio ad hoc networks (CRAHNs) is a promising solution to solve this problem. Due to its decentralised architecture, unstable network topology, highly fluctuated available spectrum, CRAHNs impose unique difficulties for spectrum sharing among CR users. A challenging question is how CR users could share vacant spectrum reasonably without centralised control. Hence, we formulate the vacant spectrum sharing among CR users in CRAHNs with evolutionary game theory (EGT). In the proposed game, we define the payoff of each CR user as a function of the achieved transmit rate and the interference to primary users. And we use replicator dynamics to model the strategy adaptation process. Simulation results suggest that the evolutionary equilibrium can be obtained through strategy adaptation and convergence is sensitive to the information latency.