IEEE Transactions on Information Forensics and Security

Two-Stage Relay Selection for Enhancing Physical Layer Security in Non-Orthogonal Multiple Access

Youhong Feng, Shihao Yan, Chenxi Liu, Zhen Yang, Nan Yang

Published Nov 26, 2018• 98 citations

Abstract

In this paper, we examine the physical layer security of a cooperative relay network where two source-destination pairs communicate through a decode-and-forward (DF) relay in the presence of multiple eavesdroppers. To safeguard the legitimate communications against eavesdropping, we propose a novel two-stage secure relay selection (TSSRS) with a non-orthogonal multiple access (NOMA) scheme to maximize the capacity of one source-destination pair, while guaranteeing the successful communication of the other source-destination pair. To explicitly reveal the benefits of our proposed scheme, we derive the exact and asymptotic expressions for its secrecy outage probability. As a benchmark, we also analyze the secrecy performance of the TSSRS strategy with an orthogonal multiple access (OMA) scheme. Both theoretical analysis and simulation results demonstrate that our proposed TSSRS-NOMA scheme significantly outperforms the TSSRS-OMA scheme when the transmit power at the source and relay is in the low and medium regimes. In addition, we show that the advantage of the TSSRS-NOMA scheme over the TSSRS-OMA scheme becomes obvious when the two source-destination pairs have profoundly different secrecy requirements.

DOI: 10.1109/tifs.2018.2883273

Related papers

Secure transmission for cooperative NOMA systems with source‐relay selection

Shu Xu, Chen Liu, Mujun Qian +2 more

Abstract Both cooperative non‐orthogonal multiple access (NOMA) and physical layer security (PLS) are promising techniques for future communication systems. This paper investigates the PLS performance of a cooperative NOMA system where multiple sources transmit a superposed message to two users by utilizing either amplify‐and‐forward (AF) or decode‐and‐forward (DF) relays in both non‐colluding and colluding eavesdropper scenarios. A source‐relay selection scheme is proposed for this system aiming at improving the secrecy performance. Additionally, the closed‐form expression of the secrecy outage probability (SOP) is derived for the proposed source‐relay selection schemes. It is demonstrated that in the proposed schemes, the theoretical results match well with the simulation results. In addition, the proposed schemes outperform the conventional OMA system in terms of SOP.

IET CommunicationsOct 30, 20216 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 TechnologyJan 21, 202256 citations

On secrecy outage probability for downlink NOMA systems with relay-antenna selection

Shu Xu, Chen Liu, Hong Wang +2 more

Abstract Secure transmission is essential for future non-orthogonal multiple access (NOMA) system. This paper investigates relay-antenna selection (RAS) to enhance physical-layer security (PLS) of cooperative NOMA system in the presence of an eavesdropper, where multiple antennas are deployed at the relays, the users, and the eavesdropper. In order to reduce expense on radio frequency (RF) chains, selection combining (SC) is employed at both the relays and the users, whilst the eavesdropper employs either maximal-ratio combining (MRC) or selection combining (SC) to process the received signals. Under the condition that the channel state information (CSI) of the eavesdropping channel is available or unavailable, two effective relay-antenna selection schemes are proposed. Additionally, the closed-form expressions of secrecy outage probability (SOP) are derived for the proposed relay-antenna selection schemes. In order to gain more deep insights on the derived results, the asymptotic performance of the derived SOP is analyzed. In simulations, it is demonstrated that the theoretical results match well with the simulation results and the SOP of the proposed schemes is less than that of the conventional orthogonal multiple access (OMA) scheme obviously.

Mar 28, 20220 citations

On secrecy outage probability for downlink NOMA systems with relay–antenna selection

Shu Xu, Chen Liu, Hong Wang +2 more

Abstract Secure transmission is essential for future non-orthogonal multiple access (NOMA) system. This paper investigates relay–antenna selection to enhance physical-layer security of cooperative NOMA system in the presence of an eavesdropper, where multiple antennas are deployed at the relays, the users, and the eavesdropper. In order to reduce expense on radio frequency chains, selection combining (SC) is employed at both the relays and the users, whilst the eavesdropper employs either maximal-ratio combining or SC to process the received signals. Under the condition that the channel state information of the eavesdropping channel is available or unavailable, two effective relay–antenna selection schemes are proposed. Additionally, the closed-form expressions of secrecy outage probability (SOP) are derived for the proposed relay–antenna selection schemes. In order to gain more deep insights on the derived results, the asymptotic performance of the derived SOP is analyzed. In simulations, it is demonstrated that the theoretical results match well with the simulation results and the SOP of the proposed schemes is less than that of the conventional orthogonal multiple access scheme obviously.

EURASIP Journal on Advances in Signal ProcessingJul 5, 20223 citations

Non-Orthogonal Multiple Access and Artificial-Noise Aided Secure Transmission in FD Relay Networks

Youhong Feng, Zhen Yang, Shihao Yan

In this paper, we investigate an artificial-noise (AN) aided secure transmission for non-orthogonal multiple access (NOMA) full-duplex (FD) relay network. We propose a novel joint NOMA and AN-aided full-duplex relay (NOMA-ANFDR) scheme to enhance the physical security. In this scheme, the optimal power allocation between the information and the AN signal is determined such that the capacity of the two end-to-end (i.e., two source-relay-destination pairs) channel are maximized to ensure the highest quality of cooperative transmission. To fully examine the benefits of the NOMA-ANFDR scheme, we derive a new closed-form expression for the secrecy outage probability.We show that the NOMA-ANFDR scheme significantly outperforms the joint NOMA and AN in half-duplex relay (NOMA-ANHDR) scheme as well as the NOMA-HDR scheme in terms of minimum secrecy outage probability and effect secrecy throughout. This result indicates that adopting the joint of FD and AN technique at relays can effectively enhance the physical layer secrecy performance in the NOMA cooperative network.

IEEE Globecom Workshops (GC Wkshps)Dec 1, 201728 citations

On Secrecy Outage Probability for Downlink NOMA Systems With Relay-Antenna Selection

Shu Xu, Chen Liu, Hong Wang +2 more

Abstract Secure transmission is essential for future non-orthogonal multiple access (NOMA) system. This paper investigates relay-antenna selection (RAS) to enhance physical-layer security (PLS) of cooperative NOMA system in the presence of an eavesdropper, where multiple antennas are deployed at the relays, the users, and the eavesdropper. In order to reduce expense on radio frequency (RF) chains, selection combining (SC) is employed at both the relays and the users, whilst the eavesdropper employs either maximal-ratio combining (MRC) or selection combining (SC) to process the received signals. Under the condition that the channel state information (CSI) of the eavesdropping channel is available or unavailable, two e↵ective relay-antenna selection schemes are proposed. Additionally, the closed-form expressions of secrecy outage probability (SOP) are derived for the proposed relay-antenna selection schemes. In order to gain more deep insights on the derived results, the asymptotic performance of the derived SOP is analyzed. In simulations, it is demonstrated that the theoretical results match well with the simulation results and the SOP of the proposed schemes is less than that of the conventional orthogonal multiple access (OMA) scheme obviously.

Dec 10, 20210 citations