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

Secrecy Performance of NOMA-Based Two-Way Communication System at Physical Layer

Shashibhushan Sharma, Kounteya Sarkar, Sudip Misra

Published Apr 1, 2026• 0 citations
Publisher

Abstract

Abstract This paper examines physical layer security in a NOMA-based two-way wireless communication system with several decode-and-forward relays and a malicious eavesdropper. We implement a partial relay selection system to maximize the secrecy capacity of a specific user's information signal. Two hops are involved in the communication process because of the half-duplex relay cooperation. A selected relay receives information from two users. The relay strengthens the signals and broadcasts them during the second hop. Additionally, a jammer transmits a jamming signal that is known to all legitimate nodes but appears as noise with the received signals at the eavesdropper. Since legitimate user nodes are already aware of the jamming signal, channel status information, and self-information, they can decode the original information in downlink mode by self-interference and successive interference cancellation. Secrecy outage probability, intercept probability, and secrecy throughput have been investigated as metrics to analyze the security, where the secrecy performance of a particular user is found to increase by $94.66\, \%$ with an increment in transmit SNR of jamming from $60\, dB$ to $70\, dB$ and increases by $90.78\, \%$ with an increment in the number of relays from 2 to 5.

DOI
10.21203/rs.3.rs-8541192/v1

Related papers

Cooperative Relay Transmission under Physical Layer Security for Non-Orthogonal Networks

Mohammed Ahmed Salem, Azlan Abd Aziz, Mohamad Yusoff Alias

In this paper, the secrecy performance for a downlink cooperative non-orthogonal multiple access (NOMA) communication system is studied under two cases. In the first case, the presence of an untrusted user is studied. While, the presence of an eavesdropper node is considered in the second case. The base station transmits superimposed information signals to the half-duplex two-way relay node. The relay amplifies-and-forwards the received signal towards the users. This paper studies the effectiveness of two factors on the secrecy performance in terms of secrecy capacity. these factors are the power allocated for each user, and the distance between the untrusted user and the cooperative relay node with respect to the strong user. Moreover, this paper proposes the shared jamming signal strategy in order to enhance the physical layer security of the cooperative NOMA in the presence of an eavesdropper node. Furthermore, simulations of the secrecy capacity are presented and compared with a conventional scheme based on null-steering jamming scheme. Based on the result the proposed technique outperforms the conventional technique in terms the of secrecy capacity.

Journal of Communications•Jan 1, 2020•5 citations

Secrecy Analysis for Cooperative NOMA Networks With Multi-Antenna Full-Duplex Relay

Yang Cao, Nan Zhao, Gaofeng Pan +4 more

In a downlink non-orthogonal multiple access (NOMA) system, the reliable transmission of cell-edge users cannot be guaranteed due to severe channel fading. On the other hand, the presence of eavesdroppers can severely threaten the secure transmission due to the open nature of wireless channel. Thus, a two-user NOMA system assisted by a multi-antenna decode-and-forward relay is considered in this paper, and a two-stage jamming scheme, full-duplex-jamming (FDJam), is proposed to ensure the secure transmission of NOMA users. In the FDJam scheme, using full-duplex, the relay transmits the jamming signal to the eavesdropper while receiving confidential messages in the first stage, and the base station generates the jamming signal in the second stage. Furthermore, we eliminate the self-interference and the jamming signal at the relay and the legitimate node, respectively, through relay beamforming. To measure the secrecy performance, analytical expressions for secrecy outage probability (SOP) are derived for both the cell-center and cell-edge users, and the asymptotic SOP analysis at high transmit power is presented as well. Moreover, two benchmark schemes, half-duplex-jamming and full-duplex-no-jamming, are also considered. Simulation results are presented to show the accuracy of the analytical expressions and the effectiveness of the proposed scheme.

IEEE Transactions on Communications•Apr 30, 2019•109 citations

Security at Physical Layer in NOMA Relaying Networks With Cooperative Jamming

Bingcai Chen, Rui Li, Qian Ning +3 more

In this letter, we consider a non-orthogonal multiple access (NOMA) network with a half-duplex (HD) decode-and-forward (DF) relay to improve physical layer security (PLS) of two users. Two legitimate users of U1 and U2 are far from the multi-antenna base station (BS). Thus, a relay with multi-antenna is used to enhance communication and obtain diversity gain. In the first stage, the BS transmits the superimposed signal to the relay via NOMA. Meanwhile, U1 generates the jamming signal to the eavesdropper (Eve). In the second stage, the relay forwards the signal to two users while the BS transmits the jamming signal to disrupt the eavesdropping. It is assumed that the Eve has strong eavesdropping ability. Thus, we need to introduce jamming to guarantee security. Furthermore, we use U1 instead of a full-duplex (FD) relay to send the jamming signal in the first stage to avoid self-interference. To measure the secrecy performance, a closed-form expression of secrecy outage probability (SOP) is derived for the two users. Simulation results are provided to verify the correctness of the proposed scheme.

IEEE Transactions on Vehicular Technology•Jan 21, 2022•56 citations

Secrecy Performance of Uplink-Downlink NOMA Network at Physical Layer

Shashibhushan Sharma, Sanjay Dhar Roy, Sumit Kundu

Physical layer security of a composite network, which includes both the uplink and downlink non-orthogonal multiple access (NOMA) system, has been analyzed. In this network, the relay is working as interface between the uplink and downlink NOMA system. Due to deep fading and shadowing, two legitimate destinations and the eavesdropper (EAV) are able to receive the information signals from the relay only. We have considered a scenario at the relay in which the relay decodes the strongest signal first when it does not know the transmit power of the information signals. To secure the confidential information, the jammer has been considered to secure the information from the EAV. For the considered model, the secrecy outage probability is analyzed as a performance metric using MATLAB based simulation. The optimal value of the relay transmit signal to noise ratio and the worst value of the transmit signal to noise ratio of the source one is indicated.

International Conference on Wireless Communications, Signal Processing and Networking (WiSPNET)•Mar 25, 2021•3 citations

Secrecy performance of an uplink-downlink cooperative PD-NOMA DF network in PLS

Thi Anh Le, H. Y. KONG

In this paper, we investigate the secrecy performance of an uplink-downlink power domain non-orthogonal multiple access (PD-NOMA) system with imperfect successive interference cancellation (SIC) in physical layer security (PLS). In the proposed system, two source users (SUs) communicate with two destination users (DUs) with the help of a cluster of multi-relay nodes using the decode-and-forward (DF) protocol in the presence of multi-eavesdroppers. These eavesdroppers try to overhear the wireless signal around the DUs. In our system, the selected DF-relay node also works as a jammer to improve security and protect confidential information from multi-eavesdroppers. In this role, the DF-relay node generates a jamming signal, creating artificial interference to reduce the quality of the eavesdropping channels. To evaluate the secrecy performance of the system, we derived the analytical expressions of the secrecy outage probability (SOP) for both DUs using three relay selection strategies over Rayleigh fading channels and used Monte Carlo simulations to confirm the accuracy of our calculations. Furthermore, we examined the effects of system parameters such as the number of eavesdroppers and DF relaying nodes, the power allocation, SIC performance, the position of eavesdropper on the SOP of the two DUs. We compared the performance of our proposed NOMA system with those of conventional orthogonal multiple access (OMA) schemes.

International Journal of Electronics•Apr 22, 2020•10 citations

Secrecy Performance on Half-Duplex Two-Way Multi-Relay Transmission Technique Under Wireless Physical Layer Security

Mohammed Ahmed Salem, Azlan Abd Aziz, Mohamad Yusoff Alias +1 more

The open broadcast nature of the wireless networks makes it vulnerable to the eavesdropper attacks. The physical layer security (PLS) is a grown research field that exploits the characteristics of the physical wireless channel to prevent the eavesdropper interruptions and attacks. The use of the cooperative relay transmission is a method to approach the physical layer security. This paper studies the secrecy performance metrics of the half-duplex two-way multi-relaying technique. A cooperative jamming protocol is proposed to enhance the physical layer security, where the destination sends jamming signals to the eavesdropper node to degrade its channel capacity. However, the relays can act as a jammer and send jamming signals to the eavesdropper node. Moreover, Simulations of the performance metrics namely the secrecy capacity (Cs) and the secrecy outage probability (SOP) applied on the technique are presented and discussed to measure the secrecy level of the proposed technique compared with an existing technique namely half-duplex one-way multi-relaying technique. Based on simulations and discussions the proposed technique outperforms the existing technique in term of secrecy performance.

International Symposium on Information Theory and its Applications•Oct 1, 2018•5 citations
Abstract This paper examines physical layer security in a NOMA-based two-way wireless communication system with several decode-and-forward relays and a malicious eavesdropper. We implement a partial relay selection system to maximize the secrecy capacity of a specific user's information signal. Two hops are involved in the communication process because of the half-duplex relay cooperation. A selected relay receives information from two users. The relay strengthens the signals and broadcasts them during the second hop. Additionally, a jammer transmits a jamming signal that is known to all legitimate nodes but appears as noise with the received signals at the eavesdropper. Since legitimate user nodes are already aware of the jamming signal, channel status information, and self-information, they can decode the original information in downlink mode by self-interference and successive interference cancellation. Secrecy outage probability, intercept probability, and secrecy throughput have been investigated as metrics to analyze the security, where the secrecy performance of a particular user is found to increase by 94.66 %94.66\, \%94.66% with an increment in transmit SNR of jamming from 60 dB60\, dB60dB to 70 dB70\, dB70dB and increases by 90.78 %90.78\, \%90.78% with an increment in the number of relays from 2 to 5.
In this paper, the secrecy performance for a downlink cooperative non-orthogonal multiple access (NOMA) communication system is studied under two cases. In the first case, the presence of an untrusted user is studied. While, the presence of an eavesdropper node is considered in the second case. The base station transmits superimposed information signals to the half-duplex two-way relay node. The relay amplifies-and-forwards the received signal towards the users. This paper studies the effectiveness of two factors on the secrecy performance in terms of secrecy capacity. these factors are the power allocated for each user, and the distance between the untrusted user and the cooperative relay node with respect to the strong user. Moreover, this paper proposes the shared jamming signal strategy in order to enhance the physical layer security of the cooperative NOMA in the presence of an eavesdropper node. Furthermore, simulations of the secrecy capacity are presented and compared with a conventional scheme based on null-steering jamming scheme. Based on the result the proposed technique outperforms the conventional technique in terms the of secrecy capacity.
In a downlink non-orthogonal multiple access (NOMA) system, the reliable transmission of cell-edge users cannot be guaranteed due to severe channel fading. On the other hand, the presence of eavesdroppers can severely threaten the secure transmission due to the open nature of wireless channel. Thus, a two-user NOMA system assisted by a multi-antenna decode-and-forward relay is considered in this paper, and a two-stage jamming scheme, full-duplex-jamming (FDJam), is proposed to ensure the secure transmission of NOMA users. In the FDJam scheme, using full-duplex, the relay transmits the jamming signal to the eavesdropper while receiving confidential messages in the first stage, and the base station generates the jamming signal in the second stage. Furthermore, we eliminate the self-interference and the jamming signal at the relay and the legitimate node, respectively, through relay beamforming. To measure the secrecy performance, analytical expressions for secrecy outage probability (SOP) are derived for both the cell-center and cell-edge users, and the asymptotic SOP analysis at high transmit power is presented as well. Moreover, two benchmark schemes, half-duplex-jamming and full-duplex-no-jamming, are also considered. Simulation results are presented to show the accuracy of the analytical expressions and the effectiveness of the proposed scheme.
In this letter, we consider a non-orthogonal multiple access (NOMA) network with a half-duplex (HD) decode-and-forward (DF) relay to improve physical layer security (PLS) of two users. Two legitimate users of U1 and U2 are far from the multi-antenna base station (BS). Thus, a relay with multi-antenna is used to enhance communication and obtain diversity gain. In the first stage, the BS transmits the superimposed signal to the relay via NOMA. Meanwhile, U1 generates the jamming signal to the eavesdropper (Eve). In the second stage, the relay forwards the signal to two users while the BS transmits the jamming signal to disrupt the eavesdropping. It is assumed that the Eve has strong eavesdropping ability. Thus, we need to introduce jamming to guarantee security. Furthermore, we use U1 instead of a full-duplex (FD) relay to send the jamming signal in the first stage to avoid self-interference. To measure the secrecy performance, a closed-form expression of secrecy outage probability (SOP) is derived for the two users. Simulation results are provided to verify the correctness of the proposed scheme.
Physical layer security of a composite network, which includes both the uplink and downlink non-orthogonal multiple access (NOMA) system, has been analyzed. In this network, the relay is working as interface between the uplink and downlink NOMA system. Due to deep fading and shadowing, two legitimate destinations and the eavesdropper (EAV) are able to receive the information signals from the relay only. We have considered a scenario at the relay in which the relay decodes the strongest signal first when it does not know the transmit power of the information signals. To secure the confidential information, the jammer has been considered to secure the information from the EAV. For the considered model, the secrecy outage probability is analyzed as a performance metric using MATLAB based simulation. The optimal value of the relay transmit signal to noise ratio and the worst value of the transmit signal to noise ratio of the source one is indicated.
In this paper, we investigate the secrecy performance of an uplink-downlink power domain non-orthogonal multiple access (PD-NOMA) system with imperfect successive interference cancellation (SIC) in physical layer security (PLS). In the proposed system, two source users (SUs) communicate with two destination users (DUs) with the help of a cluster of multi-relay nodes using the decode-and-forward (DF) protocol in the presence of multi-eavesdroppers. These eavesdroppers try to overhear the wireless signal around the DUs. In our system, the selected DF-relay node also works as a jammer to improve security and protect confidential information from multi-eavesdroppers. In this role, the DF-relay node generates a jamming signal, creating artificial interference to reduce the quality of the eavesdropping channels. To evaluate the secrecy performance of the system, we derived the analytical expressions of the secrecy outage probability (SOP) for both DUs using three relay selection strategies over Rayleigh fading channels and used Monte Carlo simulations to confirm the accuracy of our calculations. Furthermore, we examined the effects of system parameters such as the number of eavesdroppers and DF relaying nodes, the power allocation, SIC performance, the position of eavesdropper on the SOP of the two DUs. We compared the performance of our proposed NOMA system with those of conventional orthogonal multiple access (OMA) schemes.
The open broadcast nature of the wireless networks makes it vulnerable to the eavesdropper attacks. The physical layer security (PLS) is a grown research field that exploits the characteristics of the physical wireless channel to prevent the eavesdropper interruptions and attacks. The use of the cooperative relay transmission is a method to approach the physical layer security. This paper studies the secrecy performance metrics of the half-duplex two-way multi-relaying technique. A cooperative jamming protocol is proposed to enhance the physical layer security, where the destination sends jamming signals to the eavesdropper node to degrade its channel capacity. However, the relays can act as a jammer and send jamming signals to the eavesdropper node. Moreover, Simulations of the performance metrics namely the secrecy capacity (Cs) and the secrecy outage probability (SOP) applied on the technique are presented and discussed to measure the secrecy level of the proposed technique compared with an existing technique namely half-duplex one-way multi-relaying technique. Based on simulations and discussions the proposed technique outperforms the existing technique in term of secrecy performance.