This article explores the issue of physical layer security (PLS) through an analysis of a Non-Orthogonal Multiple Access (NOMA) network using multiple jamming strategies. In this network, a source transmits multiplexed signals to NOMA users when Eve is present. A jammer node adds interference signals to prevent Eve from wiretapping the secret information of the NOMA users. By deploying a new control-jammer (CJ) strategy to this network, it is possible to maximize secrecy rate at both NOMA users while working under a total power constraint. The main focus of the proposed work is on evaluating the PLS analysis of the network in terms of secrecy rate, with particular attention to the CJ condition. Additionally, the study measures the security performance difference between CJ and other jamming methods. Notably, the simulation findings confirm that CJ is effective in boosting the security of the NOMA network compared with other jamming strategies.
This article explores the issue of physical layer security (PLS) through an analysis of a Non-Orthogonal Multiple Access (NOMA) network using multiple jamming strategies. In this network, a source transmits multiplexed signals to NOMA users when Eve is present. A jammer node adds interference signals to prevent Eve from wiretapping the secret information of the NOMA users. By deploying a new control-jammer (CJ) strategy to this network, it is possible to maximize secrecy rate at both NOMA users while working under a total power constraint. The main focus of the proposed work is on evaluating the PLS analysis of the network in terms of secrecy rate, with particular attention to the CJ condition. Additionally, the study measures the security performance difference between CJ and other jamming methods. Notably, the simulation findings confirm that CJ is effective in boosting the security of the NOMA network compared with other jamming strategies.
The goal of this paper is to examine the secrecy of a new control-jammer (CJ) aided RIS enabled NOMA network. Through RIS, a source transmits a combined signal to NOMA users in the considered system model. Additionally, a jamming node transmits interference signals to prevent eavesdropping on the confidential information of users. The major focus is to improve the secrecy rate of NOMA users through the use of a CJ. Further, this study examines the physical layer security, especially secrecy rates investigation under CJ conditions, and how they compare to other strategies. Additionally, this work analyzes the previously unexplored performance gap regarding security between CJ and other jamming methods. Based on simulation results, CJ significantly enhances the network's confidentiality, which makes it an excellent choice for protecting confidential data in NOMA networks aided by RIS. Finally, this work underscores CJ as a novel approach for safeguarding sensitive information in such networks.
This paper presents a new control-jammer (CJ) strategy for improving the secrecy outage probability (SOP) in a non-orthogonal multiple access (NOMA) network with a decode-and-forward (DF) relay. The network configuration involves a source transmitting a composite signal to NOMA users with the assistance of a DF relay. In order to safeguard the users' confidential data from an eavesdropper (Eve), a jammer is deployed. The primary objective of the optimization problem is to minimize the SOP for the NOMA users in the presence of Eve. Under the CJ condition, this paper evaluates the network's physical layer security. Extensive analysis is conducted to compare the performance gap between CJ and other jamming conditions. Through comprehensive simulation results, this study showcases a substantial enhancement in secrecy performance achieved by the proposed CJ scheme at both users, demonstrating its effectiveness in improving the security of the DF relay aided NOMA network.
We have proposed and analyzed secrecy performance of a network architecture which contains a source, two destinations, a friendly jammer (FJ) and an eavesdropper (Eve). To jam the Eve in order to secure the confidential information of both users, the FJ sends a jamming signal while the source sends the combined information signal using non-orthogonal multiple access (NOMA) technique to both the users. A known jamming is considered which is known by both the users. Both the users subtract the known jamming from the received signal and then decode the information signal as per the NOMA technique. We analyzed the physical layer security of the network in terms of the secrecy outage probability (SOP) where the two users have different target secrecy rates. A closed form expression of the SOP is developed. We have analyzed the SOP under the impact of several numerical parameters such as: source transmit signal to noise ratio (SNR), FJ transmit SNR, fraction of source transmit power, and different target secrecy rates. For a fixed transmit SNR of the FJ, we obtain an optimal value of the source transmit SNR at which SOP is minimized. These analyzed results are also supported by the MATLAB based simulation results.
This study explores the physical layer security (PLS) analysis of a downlink non-orthogonal multiple access (NOMA) network under multiple eavesdropping scenarios. A composite NOMA signal is transmitted to the users enabling the users for collaborative decoding of their signals using successive-interference-cancellation (SIC). A jammer (J) node is strategically deployed to transmit the interference signals to the eavesdroppers (Eave) in the network. Additionally, the secrecy performance analysis was performed employing various jamming schemes like absence-of-jamming (AJ), unknown-jamming (UJ), and known-jamming (KJ) under both collaborative (C) and non-collaborative (NC) eavesdropping scenarios. Notably, the simulation results reveal the enhanced secrecy rates in the scenario of NC for KJ scheme making it the remarkable choice to improve the confidentiality in the network. Finally, this paper underscores KJ as a significant approach for these networks.
This paper investigates the physical layer security (PLS) of non-orthogonal multiple access (NOMA)-enabled overlay cognitive radio networks (NOMA-OCRNs), considering multiple non-colluding eavesdroppers. Here PLS is evaluated in terms of: (i) secrecy outage probability (SOP) of primary user (PU) and secondary user (SU) and (ii) system SOP (SSOP), system secrecy throughput (SST) and secrecy energy efficiency (SEE) of the network. Residual hardware impairments arising from non-ideal hardware and imperfect successive interference cancellation conditions are considered. Firstly, we derive new analytical expressions for the SOPs of PU and SU. Numerical evaluation results show that both PU as well as SU suffer very high SOPs that tend to unity in the high transmit power region. Further, RHI and i-SIC have a significant impact on the secrecy performance. To improve the PLS performance, we propose a jamming-assisted framework and develop novel analytical models for determining the SOPs of PU and SU. We derive the asymptotic SOP expressions as well. Detailed analytical and simulation results are presented to demonstrate that the proposed jamming-assisted framework leads to a significant reduction of the SOPs of both PU and SU while exhibiting considerable enhancement of SST and SEE of the network compared to the no-jammer scenario. In the final part of this paper, we utilize a deep learning framework for the precise and fast prediction of the SOPs of PU and SU, that can replace complex mathematical modeling.
NOMA (Non-Orthogonal Multiple Access) has been recognized as new multiple access technology for wireless communication networks of the fifth generation and beyond, owing to its ability to improve spectral efficiency, support massive connectivity, and provide user fairness. However, it has been observed that the superposition-based transmission principle of NOMA is highly susceptible to eavesdropping attacks, especially in an open wireless network where all wireless communications are inherently broadcast in nature. Hence, ensuring secure wireless communications for NOMA systems has now become an important area of research. This research aims to improve the secrecy level of wireless communications for NOMA systems by employing Physical Layer Security (PLS) techniques. Specifically, two prominent PLS techniques, Artificial Noise (AN) and Cooperative Jamming (CJ), have been employed to provide security against passive eavesdropping attacks. The cooperative NOMA system architecture is considered, and the secrecy enhancement is analyzed for two possible scenarios when the eavesdropper is close to the relay node and when the eavesdropper is close to the base station. The secrecy performance of the proposed system is analyzed through various parameters, namely, Secrecy Outage Probability (SOP), Secrecy Capacity (SC), Secrecy Rate (SR), and Secrecy Energy Efficiency (SEE) in terms of the Signal to Noise Ratio (SNR). The numerical results for the secrecy metrics are obtained through MATLAB-based simulations, whereas the system-level model is developed using the Simulink platform to verify the suggested system's functionality in the presence of AN and CJ for the legitimate NOMA users and the eavesdropper. The results show that the secrecy performance is significantly enhanced with the introduction of AN and CJ, and the system shows robust performance in terms of energy efficiency. This paper provides significant insights into the design of the NOMA system from the secrecy perspective and validates the potential of PLS techniques for the design of the future wireless system.