Combinatorial auction based channel allocation in cognitive radio networks

Combinatorial auction with flexible bidding formats is proposed in this paper for the channel allocation problem in cognitive radio networks. Different from other auction mechanisms, our solution includes the channel characteristic and user requirements in the biding, and therefore has more freedom to reflect the preference of secondary users on the channel selection. Four bidding formats are introduced, each of which has different emphasis to maximize social welfare of the spectrum resource. The details of each bidding format are explained, followed by the optimal solution or approximation solution proposed for each format. The approximation ratio of proposed algorithms is analyzed. Finally a numerical test is conducted in terms of social welfare and spectrum utilization. The test shows that actual approximation ratio is close to the optimal one.