Spectrum trading in cognitive radio network: A two-stage market based on contract and stackelberg game

Cognitive radio is a promising paradigm to achieve efficient utilization of spectrum resource by allowing the unlicensed users to access the licensed spectrum. Designing mechanism with proper economic incentives is essential for the success of dynamic spectrum sharing. In this paper, we study both the long-term market (i.e. contract-theoretic model) and short-term market (i.e. Stackelberg game model) between a single primary spectrum owner (PO) and multiple unlicensed secondary users (SUs) in a Market-driven secondary spectrum trading. In longterm market, we design optimal contracts, which are offered by PO. Then SUs choose whether to accept the contract based on both their demand and their types. We can show these optimal contracts maximize both PO and SUs profit. After longterm market, secondary spectrum trading enters into short-term market, where SUs can buy some amount of licensed spectrum at each time slot. We model and analyze the interactions between PO and SUs as a Stackelberg game. Finally, our simulation result demonstrates that this integrated design mechanism is effective to improve spectrum utilization and address profit maximization problem in both PO and SUs´ side.