Secrecy Rate Optimization for the Power Beacon-Assisted Secrecy Network Based on Stackelberg Game

In this paper, we consider a power beacon-assisted secrecy network, where an energy harvesting base station first harvests energy from the power beacons, and then exhausts the energy to transmit the information to the legitimate user in the presence of an eavesdropper. The legitimate user pays the base station for its secured communication based on the achieved secrecy rate. We formulate this secrecy rate problem into a Stackelberg game, where the base station and the power beacons are the leader and the follower of the game, respectively. For the proposed game, the base station and power beacons try to maximize their own revenues. We then investigate a Stackelberg equilibrium solution for the formulated game. Numerical results show that the revenue functions of the base station and the power beacons are concave function and the Stackelberg equilibrium solution has been validated. In addition, the proposed scheme can achieve better performance as the value of the gain unit throughput increase, which also leads to a slightly small energy transfer time-fraction value.