Secure Transmission With Guaranteed User Satisfaction in Heterogeneous Networks: A Two-Level Stackelberg Game Approach

In this paper, secure transmission in a heterogeneous network in the presence of multiple eavesdroppers is studied. A game-theoretic framework is proposed to enhance the security of the macro base station (MBS), while guaranteeing user satisfaction of the small base stations (SBSs) by exploiting the cooperation and competition among the entire network. Specifically, a two-level Stackelberg game is formulated, where the MBS employs a set of competing jamming SBSs to jam the eavesdroppers at the top level, and each employed jamming SBS may require offloading service from multiple competing helping SBSs in its cluster at the bottom level if needed. Two levels of user satisfaction are investigated at the bottom level, respectively. One is fixed with the priority given to user satisfaction over the profit and the other is flexible with a balance between user satisfaction and the profit. The Stackelberg equilibrium of the proposed game is derived and analyzed from the economics viewpoint. An iterative algorithm is also proposed to obtain the optimal solutions. Numerical results are provided to verify the theoretical analysis and show the effectiveness of the proposed algorithm.