Covert communication based on energy harvesting and cooperative jamming.

To prevent detection of communication between legitimate users by warden and guarantee a strong security in wireless networks, covert communication technique is recommended. The covert communication is based on hiding the main message in the background of noise which poses challenges such as low transmission rate. On the other hand, the transmit power in the conventional networks is supplied by separate built-in batteries, which are sometimes hard to be recharged or replaced especially in the military applications. In this work, to tackle the low transmission rate, we employ three dimensions beamforming in which we can focus the main beam on the legitimate user and minimize the leakage information at the warden. Moreover, in the proposed network, we intend to employ cooperative jamming (CJ) to increase covert rat in which the jammer is equipped to multiple antennas. Furthermore, to tackle the recharging or replacing batteries in the proposed network, we employ the energy harvesting (EH) technique. The simulation results reveal that the energy harvesting from the jammer's signal reduce the total power consumption. Moreover, the simulation results show that the optimality gap is about 50% according to energy harvesting technique, and the 3D beamforming increases covert rate about 70% compared to two-dimensional beamforming method. [ABSTRACT FROM AUTHOR]