The security and privacy of wireless communications have always been top priorities. In this paper, a new frequency hopping (FH) scheme is proposed for wireless covert communication systems, which can simultaneously achieve high reliability, covertness, and anti-jamming capability. In particular, a high level of covertness is attained by exploiting the noise uncertainty present in the environment. Furthermore, channel equivocation is introduced to ensure the anti-interception and anti-jamming capabilities of FH systems. Specifically, we formulate a joint optimization problem of transmit power and frequency allocation to maximize the warden’s detection error probability, subject to transmission reliability and channel equivocation constraints. The formulated problem is then solved using an alternating optimization algorithm. Subsequently, the final FH sequence is generated by mapping the obtained probability vector to a random sequence. Numerical results demonstrate that our proposed covert FH scheme can achieve superior comprehensive performance (i.e., high reliability, covertness, anti-jamming capability, and sequence unpredictability) compared with other typical schemes.

As the mainstay of the Internet of Things (IoT), data carries the vital memory of the future intelligent society. However, because of the inherent broadcast and open characteristics of wireless channels, transmitting data securely and reliably is a huge challenge for IoT. In this paper, a covert transmission control scheme with high reliability and anti-jamming capability is proposed to deal with the above challenges, by exploiting the artificial noise emitted by cooperative interference sources in the environment. Specifically, with the aim of maximizing the warden's detection error probability, the transmit power and frequency are jointly optimized under the constraints of transmission reliability and channel equivocation. The Block Coordinate Descent (BCD) algorithm is used to solve the formulated optimization problem. Numerical results demonstrate the superiority of our proposed scheme, which can simultaneously achieve high reliability, covertness, and anti-jamming capability.