A Stackelberg Game for Cooperative Cognitive Wireless Powered Communication Networks with Multiple Primary Users

We consider a cooperative cognitive wireless powered communication network consisting of a cognitive base station (CBS), multiples secondary users (SUs) and multiple wireless powered primary users (PUs). A two stage protocol is adopted, in which the CBS transmits information bearing signals and the PUs harvest energy from these RF signals first, and then the PUs transmit information based on the harvested energy. We assume that the CBS prices the energy transferred to the PUs. The interaction between the CBS and the PUs is modeled as a Stackelberg game, in which the CBS acts as a leader to determine the prices and the time allocation, while the PUs act as followers to determine the required transmit power of the CBS. An algorithm is proposed to achieve the Stackelberg equilibrium. It is shown that the proposed algorithm outperforms the equal-time benchmark algorithm in terms of the utility of the CBS, and is inferior to the equal-time benchmark algorithm in terms of the average utility of the PUs.