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

SiPS ... design and implementation - IEEE Workshop on Signal Processing Systems

Physical-Layer Security for THz Communications via Orbital Angular Momentum Waves

Jongchan Woo, Muhammad Ibrahim Wasiq Khan, Mohamed I. Ibrahim, Ruonan Han, Anantha P. Chandrakasan, Rabia Tugce Yazicigil

Published Nov 2, 2022• 18 citations
Publisher

Abstract

This paper presents a physically-secure wireless communication system utilizing orbital angular momentum (OAM) waves at 0.31THz. A trustworthy key distribution mechanism for symmetric key cryptography is proposed by exploiting random hopping among the orthogonal OAM-wave modes and phases. Keccak-f[400] based pseudorandom number generator provides randomness to phase distribution of OAM-wave modes for additional security. We assess the security vulnerabilities of using OAM modulation in a THz communication system under various physical-layer threat models as well as analyze the effectiveness of these threat models for varying attacker complexity levels under different conditions.

DOI
10.1109/sips55645.2022.9919249

Related papers

Physical Layer Security of THz Orbital Angular Momentum MIMO Systems with a Successive Interference Cancellation Eavesdropper

Duschia M. Bodet, Innem V. A. K. Reddy, Josep Miquel Jornet

Spatial multiplexing is not always feasible in terahertz and sub-terahertz (THz) MIMO channels due to the primarily line-of-sight propagation, but recent works have explored the possibility of using orbital angular momentum (OAM) to enable multiplexing in line-of-sight scenarios. This paper explores a certain physical-layer security risk and a corresponding mitigation strategy for THz MIMO systems using orbital angular momentum (OAM). A novel successive interference cancellation eavesdropping attack is introduced for OAM-MIMO THz systems, and simulations demonstrate that the security of the link decreases in the far field. A security countermeasure is introduced and proven to be effective in physically protecting the communications link.

Globecom•Dec 8, 2025•0 citations

Physical Layer Key Generation for Secure OAM Communication Systems

Mengyi Zhang, Zijie Ji, Yan Zhang +3 more

In this paper, we propose a physical layer secret key (PLSK) generation scheme for secure encrypted transmissions in orbital angular momentum (OAM) communication systems which improves the secret key capacity via taking advantage of OAM orthogonal modes. Based on the line-of-sight (LoS) quasi-static channel conditions in OAM systems, we propose a mode-based active defense phase in the PLSK scheme to invalidate keys generated by an eavesdropper when it is extremely close to the legitimate user. Our simulation results highlight that the key information generated by the eavesdropper is almost zero in the case of highly correlated legitimate and eavesdropping channels under LoS conditions. In addition, our proposed OAM PLSK scheme achieves a higher key generation rate (KGR) than existing works since mode-based active defense can disrupt the process of PLSK by the eavesdropper.

IEEE Transactions on Vehicular Technology•Jul 28, 2022•12 citations

Physical-layer Key Generation for Orthogonal Frequency Division Multiplexing-Orbital Angular Momentum Systems

Yun Xin, Jiawei Li, Dawei Wang +5 more

In this paper, we propose a novel physical-layer key generation (PKG) scheme for orthogonal frequency division multiplexing-orbital angular momentum (OFDM-OAM) systems to significantly enhance the confidentiality capacity (CC). In the proposed scheme, we first establish the OAM channel model under uniform circular array (UCA) misalignment in the line-of-sight (LoS) channel. Facing the risk of information leakage during key negotiation, we couple key generation with the OFDM communication process. Then, we analyze the CC of the OFDM-OAM system and derive its closed-form expression. Simulation results illustrate that the proposed OFDM-OAM PKG scheme has achieved high CC compared with existing works. In addition, as the offset angle of the eavesdropper’s UCA increases, the CC increases, and the bit error rate (BER) of the eavesdropper tends to be 0.5.

IEEE Vehicular Technology Conference•Oct 19, 2025•1 citation

Spatial modes-based physical-layer security

Ivan B. Djordjević, Xiaole Sun

The growth of the Internet traffic does not appear to be levelling off any time soon and it is projected to continue to grow exponentially in the years to come. Although there are many proposals on how to deal with the incoming bandwidth capacity crunch, the security of optical networks seems to be almost completely neglected. By taping out the portion of DWDM signal, the huge amount of data can be compromised. Therefore, the security of future optical networks is becoming one of the major issues to be addressed sooner rather than later. To address the security issues of future optical networks the quantum key distribution (QKD) and chaotic cryptography have been proposed. To avoid the high cost of QKD, the properly designed fiber Bragg gratings (FBGs) as optical encryption devices have been advocated recently. In this invited paper, we follow a different strategy. It is well known that we can associate with a photon both spin angular momentum (SAM), related to polarization; and orbital angular momentum (OAM), related to azimuthal dependence of the complex electric field. Because the OAM eigenstates are orthogonal, this additional degree of freedom can be utilized for the physical-layer security in optical networks. Given that the spatial modes in spatial domain multiplexing (SDM) fibers such as few-mode fibers (FMFs), few-core fibers (FCFs), and few-mode-few-core fibers (FMFCFs) can be decomposed in terms of OAM eigenkets, the OAM can be used to enable the physical-layer security in both fiber-optics- and free-space optics-based optical networks.

International Conference on Transparent Optical Networks•Jul 1, 2016•6 citations

High-Capacity Quantum Secure Direct Communication With Orbital Angular Momentum of Photons

Sichen Mi, Tie-Jun Wang, Guang-Sheng Jin +1 more

Orbital angular momentum (OAM) states of photons span a high-dimensional Hilbert space, and by using it, higher information capacity and enhanced security can be achieved for both classical communication and quantum key distribution. In this work, we propose a feasible basis-independent encoding scheme for OAM states and show its application in high-dimensional quantum secure direct communication, which enables direct transmission of meaningful messages, in addition to random secret key establishing. Imperfections of optical components may reduce the efficiency of the encoding scheme and, thus, the channel capacity. We discuss the optimal input distribution under realistic conditions to achieve maximal mutual information and an alternative solution using a different set of mutually unbiased bases in the case of a prime-dimensional quantum system.

IEEE photonics journal•Aug 21, 2015•50 citations

Secure Range-Dependent Transmission With Orbital Angular Momentum

Junshan Luo, Shilian Wang, Fanggang Wang

Orbital angular momentum (OAM) provides an additional degree of freedom for information transmission. However, wireless transmissions with OAM are challenged by secrecy issues since the OAM modes can be observed over a wide range along the beam axis, and it allows that the eavesdroppers intercept the information bits encoded on the OAM modes. In this letter, targeting against unintended receivers, we propose a secure range-dependent transmission scheme with OAM radio beams generated by the frequency diverse array (FDA). Specifically, we consider a line-of-sight communication link overheard by an unknown eavesdropper. The transmitter employs FDA of antennas to generate range-dependent OAM radio beams and target at the legitimate receiver, in which the confidential information is encoded on the OAM modes. The eavesdropper outside the target region observes distorted OAM modes and thus is unable to recover the secret messages. The proposed scheme enhances the security of OAM mode modulation and achieves higher energy efficiency compared to the conventional secure transmission schemes with artificial noise.

IEEE Communications Letters•May 10, 2019•22 citations
This paper presents a physically-secure wireless communication system utilizing orbital angular momentum (OAM) waves at 0.31THz. A trustworthy key distribution mechanism for symmetric key cryptography is proposed by exploiting random hopping among the orthogonal OAM-wave modes and phases. Keccak-f[400] based pseudorandom number generator provides randomness to phase distribution of OAM-wave modes for additional security. We assess the security vulnerabilities of using OAM modulation in a THz communication system under various physical-layer threat models as well as analyze the effectiveness of these threat models for varying attacker complexity levels under different conditions.
Spatial multiplexing is not always feasible in terahertz and sub-terahertz (THz) MIMO channels due to the primarily line-of-sight propagation, but recent works have explored the possibility of using orbital angular momentum (OAM) to enable multiplexing in line-of-sight scenarios. This paper explores a certain physical-layer security risk and a corresponding mitigation strategy for THz MIMO systems using orbital angular momentum (OAM). A novel successive interference cancellation eavesdropping attack is introduced for OAM-MIMO THz systems, and simulations demonstrate that the security of the link decreases in the far field. A security countermeasure is introduced and proven to be effective in physically protecting the communications link.
In this paper, we propose a physical layer secret key (PLSK) generation scheme for secure encrypted transmissions in orbital angular momentum (OAM) communication systems which improves the secret key capacity via taking advantage of OAM orthogonal modes. Based on the line-of-sight (LoS) quasi-static channel conditions in OAM systems, we propose a mode-based active defense phase in the PLSK scheme to invalidate keys generated by an eavesdropper when it is extremely close to the legitimate user. Our simulation results highlight that the key information generated by the eavesdropper is almost zero in the case of highly correlated legitimate and eavesdropping channels under LoS conditions. In addition, our proposed OAM PLSK scheme achieves a higher key generation rate (KGR) than existing works since mode-based active defense can disrupt the process of PLSK by the eavesdropper.
In this paper, we propose a novel physical-layer key generation (PKG) scheme for orthogonal frequency division multiplexing-orbital angular momentum (OFDM-OAM) systems to significantly enhance the confidentiality capacity (CC). In the proposed scheme, we first establish the OAM channel model under uniform circular array (UCA) misalignment in the line-of-sight (LoS) channel. Facing the risk of information leakage during key negotiation, we couple key generation with the OFDM communication process. Then, we analyze the CC of the OFDM-OAM system and derive its closed-form expression. Simulation results illustrate that the proposed OFDM-OAM PKG scheme has achieved high CC compared with existing works. In addition, as the offset angle of the eavesdropper’s UCA increases, the CC increases, and the bit error rate (BER) of the eavesdropper tends to be 0.5.
The growth of the Internet traffic does not appear to be levelling off any time soon and it is projected to continue to grow exponentially in the years to come. Although there are many proposals on how to deal with the incoming bandwidth capacity crunch, the security of optical networks seems to be almost completely neglected. By taping out the portion of DWDM signal, the huge amount of data can be compromised. Therefore, the security of future optical networks is becoming one of the major issues to be addressed sooner rather than later. To address the security issues of future optical networks the quantum key distribution (QKD) and chaotic cryptography have been proposed. To avoid the high cost of QKD, the properly designed fiber Bragg gratings (FBGs) as optical encryption devices have been advocated recently. In this invited paper, we follow a different strategy. It is well known that we can associate with a photon both spin angular momentum (SAM), related to polarization; and orbital angular momentum (OAM), related to azimuthal dependence of the complex electric field. Because the OAM eigenstates are orthogonal, this additional degree of freedom can be utilized for the physical-layer security in optical networks. Given that the spatial modes in spatial domain multiplexing (SDM) fibers such as few-mode fibers (FMFs), few-core fibers (FCFs), and few-mode-few-core fibers (FMFCFs) can be decomposed in terms of OAM eigenkets, the OAM can be used to enable the physical-layer security in both fiber-optics- and free-space optics-based optical networks.
Orbital angular momentum (OAM) states of photons span a high-dimensional Hilbert space, and by using it, higher information capacity and enhanced security can be achieved for both classical communication and quantum key distribution. In this work, we propose a feasible basis-independent encoding scheme for OAM states and show its application in high-dimensional quantum secure direct communication, which enables direct transmission of meaningful messages, in addition to random secret key establishing. Imperfections of optical components may reduce the efficiency of the encoding scheme and, thus, the channel capacity. We discuss the optimal input distribution under realistic conditions to achieve maximal mutual information and an alternative solution using a different set of mutually unbiased bases in the case of a prime-dimensional quantum system.
Orbital angular momentum (OAM) provides an additional degree of freedom for information transmission. However, wireless transmissions with OAM are challenged by secrecy issues since the OAM modes can be observed over a wide range along the beam axis, and it allows that the eavesdroppers intercept the information bits encoded on the OAM modes. In this letter, targeting against unintended receivers, we propose a secure range-dependent transmission scheme with OAM radio beams generated by the frequency diverse array (FDA). Specifically, we consider a line-of-sight communication link overheard by an unknown eavesdropper. The transmitter employs FDA of antennas to generate range-dependent OAM radio beams and target at the legitimate receiver, in which the confidential information is encoded on the OAM modes. The eavesdropper outside the target region observes distorted OAM modes and thus is unable to recover the secret messages. The proposed scheme enhances the security of OAM mode modulation and achieves higher energy efficiency compared to the conventional secure transmission schemes with artificial noise.