Aggregation-based spectrum allocation algorithm in cognitive radio networks

In cognitive radio networks, the idle spectrum bands that cognitive users sensed are usually discontinuous. Only one idle spectrum band may not be able to fulfill cognitive users´ bandwidth requirements. In order to let cognitive users access allocated spectrum bands successfully and further improve the efficiency of spectrum utilization, we propose spectrum aggregation-based graph coloring algorithm (SAGCA), a spectrum allocation algorithm in cognitive radio networks. SAGCA considers bandwidth requirements of cognitive users and limitation of spectrum range that equipment can utilize due to hardware constraint. Numerical results show that the proposed algorithm can achieve greater performance in total bandwidth and percentage of cognitive users that networks can support compared to the original algorithm.