Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

arXiv:2407.13898

Fundamental Scaling Laws of Covert Communication in the Presence of Block Fading

Amir Reza Ramtin, Dennis Goeckel, Don Towsley

Published Jul 18, 2024• 0 citations
arXivHTMLPDF

Abstract

Covert communication is the undetected transmission of sensitive information over a communication channel. In wireless communication systems, channel impairments such as signal fading present challenges in the effective implementation and analysis of covert communication systems. This paper generalizes early work in the covert communication field by considering asymptotic results for the number of bits that can be covertly transmitted in $n$ channel uses on a block fading channel. Critical to the investigation is characterizing the performance of optimal detectors at the adversary. Matching achievable and converse results are presented.

DOI
10.48550/arxiv.2407.13898

Related papers

Covert communications with extremely low power under finite block length over slow fading

Haoyue Tang, Jintao Wang, Yahong Rosa Zheng

This paper investigates the achievable message transmission rate of covert communication over slow fading channels where the channel coefficient remains unchanged over a finite transmission block. Such communication is often implemented with an extremely low transmission power aiming to achieve low probability of detection by the eavesdropper and under tolerable probability of decoding error for the legitimate receiver. The exact expression of achievability and asymptotic covert bounds are derived, which are shown in accordance with the square root law in AWGN (Additive White Gaussian Noise) channels with large transmission blocks. The case that the eavesdropper has unknown channel state information is also studied in the paper.

IEEE Conference on Computer Communications Workshops (INFOCOM WKSHPS)•Apr 1, 2018•16 citations

Covert Communication in the Presence of an Uninformed Jammer

Tamara V. Sobers, Boulat A. Bash, Saikat Guha +2 more

Recent work has established that when transmitter Alice wishes to communicate reliably to recipient Bob without detection by warden Willie, with additive white Gaussian noise (AWGN) channels between all parties, communication is limited to O(√n) bits in n channel uses. However, this assumes that Willie has an accurate statistical characterization of the channel. When Willie has uncertainty about such and his receiver is limited to a threshold test on the received power, Alice can transmit covertly with a power that does not decrease with n, thus conveying O(n) bits covertly and reliably in n uses of an AWGN channel. Here, we consider covert communication of O(n) bits in n channel uses while generalizing the environment and removing any restrictions on Willie's receiver. We assume that an uninformed “jammer” is present to help Alice, and we consider AWGN and block fading channels. In some scenarios, Willie's optimal detector is a threshold test on the received power. When the channel between the jammer and Willie has multiple fading blocks per codeword, a threshold test on the received power is not optimal. However, we establish that Alice can remain covert with a transmit power that does not decrease with n even when Willie employs an optimal detector.

IEEE Transactions on Wireless Communications•Jun 30, 2017•451 citations

Covert Communication in the Presence of an Uninformed Jammer

Tamara V. Sobers, Boulat A. Bash, Saikat Guha +2 more

Recent work has established that when transmitter Alice wishes to communicate reliably to recipient Bob without detection by warden Willie, with additive white Gaussian noise (AWGN) channels between all parties, communication is limited to $\mathcal{O}(\sqrt{n})$ bits in $n$ channel uses. However, this assumes Willie has an accurate statistical characterization of the channel. When Willie has uncertainty about such and his receiver is limited to a threshold test on the received power, Alice can transmit covertly with a power that does not decrease with $n$, thus conveying $\mathcal{O}(n)$ bits covertly and reliably in $n$ uses of an AWGN channel. Here, we consider covert communication of $\mathcal{O}(n)$ bits in $n$ channel uses while generalizing the environment and removing any restrictions on Willie's receiver. We assume an uninformed "jammer" is present to help Alice, and we consider AWGN and block fading channels. In some scenarios, Willie's optimal detector is a threshold test on the received power. When the channel between the jammer and Willie has multiple fading blocks per codeword, a threshold test on the received power is not optimal. However, we establish that Alice can remain covert with a transmit power that does not decrease with $n$ even when Willie employs an optimal detector.

arXiv:1608.00698•Aug 2, 2016•2 citations

Low-to-no-power covert communication based on energy dispersion

Jianping An, Haichuan Ding, Shuai WANG

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.

Scientia Sinica Informationis•May 19, 2023•1 citation

Covert Communications: A Comprehensive Survey

Xinying Chen, Jianping An, Zehui Xiong +4 more

Information security has always been a critical issue in wireless networks. Apart from other secure techniques, covert communication emerges as a potential solution to security for wireless networks owing to its high-security level. In covert communication networks, the transmitter hides the transmitted signals into environmental or artificial noise by introducing randomness to avoid detection at the warden. By eliminating the existence of transmitted signals at the warden, information security can be preserved more solidly than other secure transmission techniques, i.e., without noticing the existence. Due to the promising security protection, covert communication has been successfully utilized in tremendous wireless communication scenarios. However, fundamental challenges in its practical implementation still exist, e.g., the effectiveness of randomness utilization, the low signal-to-interference-plus-noise ratio at legitimate users, etc. In this survey, we demonstrate a comprehensive review concentrating on the applications, solutions, and future challenges of covert communications. Specifically, the covert principle and research categories are first introduced. Then, the applications in the networks with different topologies and the effective covert techniques in the existing literature are reviewed. We also discuss the potential implementation of covert communications in future networks and the open challenges.

IEEE Communications Surveys & Tutorials•Jan 1, 2023•380 citations

Limits of Covert Communication over AWGN Channels in the Presence of Multiple Wardens

Ranran Sun, Shuiguang Zeng, Xinghui Zhu

Covert communication has recently been recognized as a highly promising security technology that enables a transmitter Alice to reliably and covertly communicate with a receiver Bob without being detected by a malicious warden. Available works on covert communication mainly focus on scenarios with only one warden, while the fundamental limits of covert communication in more practical multi-warden scenarios remain largely unknown. This paper therefore investigates the fundamental limits of covert communication over an additive white Gaussian noise (AWGN) channel in the presence of multiple wardens. We first consider a scenario with two wardens and derive the maximum number of bits Alice can transmit to Bob over n channel uses while ensuring a negligible detection probability at wardens. We then generalize this result to the multi-warden case and find that the minimal power of wardens has impacts on the scaling law of the performance limits of covert communication over AWGN channels.

International Conference on Networking and Network Applications (NaNA)•Oct 1, 2018•6 citations
Covert communication is the undetected transmission of sensitive information over a communication channel. In wireless communication systems, channel impairments such as signal fading present challenges in the effective implementation and analysis of covert communication systems. This paper generalizes early work in the covert communication field by considering asymptotic results for the number of bits that can be covertly transmitted in nnn channel uses on a block fading channel. Critical to the investigation is characterizing the performance of optimal detectors at the adversary. Matching achievable and converse results are presented.
This paper investigates the achievable message transmission rate of covert communication over slow fading channels where the channel coefficient remains unchanged over a finite transmission block. Such communication is often implemented with an extremely low transmission power aiming to achieve low probability of detection by the eavesdropper and under tolerable probability of decoding error for the legitimate receiver. The exact expression of achievability and asymptotic covert bounds are derived, which are shown in accordance with the square root law in AWGN (Additive White Gaussian Noise) channels with large transmission blocks. The case that the eavesdropper has unknown channel state information is also studied in the paper.
Recent work has established that when transmitter Alice wishes to communicate reliably to recipient Bob without detection by warden Willie, with additive white Gaussian noise (AWGN) channels between all parties, communication is limited to O(√n) bits in n channel uses. However, this assumes that Willie has an accurate statistical characterization of the channel. When Willie has uncertainty about such and his receiver is limited to a threshold test on the received power, Alice can transmit covertly with a power that does not decrease with n, thus conveying O(n) bits covertly and reliably in n uses of an AWGN channel. Here, we consider covert communication of O(n) bits in n channel uses while generalizing the environment and removing any restrictions on Willie's receiver. We assume that an uninformed “jammer” is present to help Alice, and we consider AWGN and block fading channels. In some scenarios, Willie's optimal detector is a threshold test on the received power. When the channel between the jammer and Willie has multiple fading blocks per codeword, a threshold test on the received power is not optimal. However, we establish that Alice can remain covert with a transmit power that does not decrease with n even when Willie employs an optimal detector.
Recent work has established that when transmitter Alice wishes to communicate reliably to recipient Bob without detection by warden Willie, with additive white Gaussian noise (AWGN) channels between all parties, communication is limited to O(n)\mathcal{O}(\sqrt{n})O(n​) bits in nnn channel uses. However, this assumes Willie has an accurate statistical characterization of the channel. When Willie has uncertainty about such and his receiver is limited to a threshold test on the received power, Alice can transmit covertly with a power that does not decrease with nnn, thus conveying O(n)\mathcal{O}(n)O(n) bits covertly and reliably in nnn uses of an AWGN channel. Here, we consider covert communication of O(n)\mathcal{O}(n)O(n) bits in nnn channel uses while generalizing the environment and removing any restrictions on Willie's receiver. We assume an uninformed "jammer" is present to help Alice, and we consider AWGN and block fading channels. In some scenarios, Willie's optimal detector is a threshold test on the received power. When the channel between the jammer and Willie has multiple fading blocks per codeword, a threshold test on the received power is not optimal. However, we establish that Alice can remain covert with a transmit power that does not decrease with nnn even when Willie employs an optimal detector.
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.
Information security has always been a critical issue in wireless networks. Apart from other secure techniques, covert communication emerges as a potential solution to security for wireless networks owing to its high-security level. In covert communication networks, the transmitter hides the transmitted signals into environmental or artificial noise by introducing randomness to avoid detection at the warden. By eliminating the existence of transmitted signals at the warden, information security can be preserved more solidly than other secure transmission techniques, i.e., without noticing the existence. Due to the promising security protection, covert communication has been successfully utilized in tremendous wireless communication scenarios. However, fundamental challenges in its practical implementation still exist, e.g., the effectiveness of randomness utilization, the low signal-to-interference-plus-noise ratio at legitimate users, etc. In this survey, we demonstrate a comprehensive review concentrating on the applications, solutions, and future challenges of covert communications. Specifically, the covert principle and research categories are first introduced. Then, the applications in the networks with different topologies and the effective covert techniques in the existing literature are reviewed. We also discuss the potential implementation of covert communications in future networks and the open challenges.
Covert communication has recently been recognized as a highly promising security technology that enables a transmitter Alice to reliably and covertly communicate with a receiver Bob without being detected by a malicious warden. Available works on covert communication mainly focus on scenarios with only one warden, while the fundamental limits of covert communication in more practical multi-warden scenarios remain largely unknown. This paper therefore investigates the fundamental limits of covert communication over an additive white Gaussian noise (AWGN) channel in the presence of multiple wardens. We first consider a scenario with two wardens and derive the maximum number of bits Alice can transmit to Bob over n channel uses while ensuring a negligible detection probability at wardens. We then generalize this result to the multi-warden case and find that the minimal power of wardens has impacts on the scaling law of the performance limits of covert communication over AWGN channels.