多维域低零功率通信

With advances in computing and signal processing technologies, wireless communication systems are facing severe security threats, necessitating effective countermeasures. Unlike traditional secure communication schemes, covert communication should hide not only information content but also data transmission activity from adversaries. To this end, we propose an energy dispersion-based covert communication scheme to ensure that communication signal detection by adversaries has close-to-zero probability. The proposed scheme spreads the energy of transmitted signals throughout the whole parameter space to limit the signal detection capability of adversaries and improve the covertness of signal transmission. By defining the covertness of transmitted signals with respect to the adversaries’ prior knowledge of parameter spaces, we study the modeling of energy dispersion-based covert communication systems and analyze their fundamental performance limitations. With these analytical results, we further investigate the impacts of adversaries’ prior knowledge on the achievable throughput of covert communications. These results demonstrate that the dispersion of signal energy can degrade the performance of coherent signal detection so that the achievable throughput of the covert communication system does not necessarily follow the power-law decrease observed in existing work on the low probability of detection communications. This work lays the theoretical foundation for covert communication based on energy dispersion.