The IEEE 802.22 standard is the first proposed standard for the cognitive radio networks in which a set of base stations (BSs) make opportunistic spectrum access to provide wireless access to the customer-premise equipments (CPE) within their cells in wireless regional area networks (WRAN). The channel assignment and power control must be carried out in BSs and CPEs, such that no excessive interference is caused to the users of the primary network. We use a game-theoretic model to analyze the non- cooperative behavior of the secondary users in IEEE 802.22 networks. We first show the existence of Nash equilibrium in a 2-cell non-cooperative game model, where the players (BSs) want to increase their coverage range. Then we extend our game to an N-player non-cooperative game where the players aim at maximizing the number of subscribers (i.e., CPEs). We conclude that the non- cooperative behavior of the players might result in a small number of supported CPEs and this can be solved by cooperative techniques, such as the Nash bargaining solution. Numerical results show that our proposed Nash bargaining solution can significantly increase the efficiency of the opportunistic spectrum allocation.