Abstract:

Cognitive radio becomes a promising approach to increase spectrum efficiency, the important of which is dynamic spectrum access. Spectrum allocation based on graph theoretical model is analyzed, and an improved spectrum allocation algorithm is proposed to solve the dynamic spectrum access of cognitive radio networks. On the basis of previous allocation, it reduces the impact of secondary users’ mobility by releasing corresponding conflicted channels and searching for available channels. Further simulation shows that the algorithm can reduce the number of reallocated secondary users without significantly reducing system utilization, and the complexity of dynamic spectrum allocation is also reduced.