Improve physical layer security in cooperative wireless network using distributed auction games

In this paper, we investigate a cooperative wireless network with jamming-based secure communications, where a friendly jammer can transmit jamming signals to interfere the malicious eavesdropper. We find that the secrecy rate of the source-destination link can be effectively improved with the help of the friendly jammer, and each source intends to obtain optimal jamming power from the friendly jammer to maximize its secrecy rate for data transmission. We then formulate this power allocation problem as an auction game and propose two distributively auction-based power allocation schemes, which are power allocation using Traditional Ascending Clock Auction (ACA-T) and power allocation using Alternative Ascending Clock Auction (ACA-A), considering the friendly jammer as the auctioneer and the sources as the bidders. In addition, we prove that both the proposed schemes can converge in a finite number of iterations. We also prove that the ACA-A scheme is cheat-proof while the ACA-T scheme is not. Finally, simulation results are presented to demonstrate the efficiency of the proposed auction-based schemes in improving secrecy rate of wireless networks.