Multi-Antenna Covert Communication Based on Spectrum Mask

In this paper, a spectrum mask-based covert communication strategy is proposed in the multi-antenna network. By adopting the transmission strategy of that using maximum ratio transmission (MRT) at the transmitter side and superimposing improper Gaussian signaling (IGS) on the overt channel, the covertness of the multi-antenna covert system is enhanced. The joint optimization problem of the covert transmit power and the IGS factor is proposed to maximize the covert throughput based on the analyzing of the detection performance of the eavesdropper. Simulation results demonstrate that the proposed scheme can improve the covert communication performance of the multi-antenna system under given covertness constraint.