Two-Layer Game Based Covert Communication Strategy Against Jamming Attack Oriented Warden

This paper considers the problem of covert communication threatened by jamming attacks. The transmitter (T) randomly selects a portion of the available channels to transmit uplink signals. The receiver (R) uses maximal-ratio combining to receive the uplink signals. Warden (W) detects the uplink signals in each channel by solving ternary hypothesis testing and jams the channel according to the detection results. In order to jam the activated channel accurately, W formulates his utility function (UF) as maximize the detection probability. His UF subject to a false alarm probability. In order to confuse W, the cooperative jammer (J) sends artificial noise in randomly selected part of all available channels except the uplink activation channel. Minimizing the uplink signal detection probability and maximizing the detection error probabilities are UF of A and J, respectively, both are subject to SNR. We formulate this problem as a two-layer game model. In addition, we analyze the proposed game and obtain the solution of tripartite strategies. Simulation results indicate that the proposed scheme achieves better transmission performance and lower detection probability.