Abstract—Recently various cognitive radio network models are suggested and analyzed. In particular, cooperative cognitive
radio network model considers cooperative relaying of secondary users in cognitive radio networks, which utilize the spectrum
occupancy efficiently. However, such cooperation may not occur when secondary users have a better alternative, spectrum leasing. Therefore, in this paper, we study the impact of leasing in a network model with game-theoretic analysis. We first show the importance of the problem with a simple two-secondary-user game. Finally we extend our formulation and analysis to explicitly incorporate the effects of lease strength for a n-secondary-user game given the occupancy model of primary users.