Physical layer security for multiuser two-way relay using distributed auction game

In this paper, we investigate jamming power allocation to improve physical layer security in a multiuser two-way relay network, where several communication pairs, one untrusted relay and one friendly jammer are involved. The untrusted relay helps these pairs to forward information and tries to eavesdrop simultaneously. In order to deteriorate the eavesdropping link and to improve physical layer security, we introduce a friendly jammer to impose interference on the relay. We formulate the jamming power allocation as an ACA-A game, where the friendly jammer is modeled as the auctioneer and the pairs are regarded as the bidders. The convergence and the cheat-proof property of the proposed auction are analyzed and proved. Finally, we also carry out some numerical results to validate the effectiveness of the proposed ACA-A based power allocation algorithm.