Secrecy Outage Performance Analysis for Cooperative NOMA Over Nakagami- $m$ Channel

IEEE Access

Xin Peng¹  Wenwu Xie¹  Chao Yu¹  Hak-Lim Ko² 

[1] College of Information Science and Engineering, Hunan Institute of Science and Technology, Yueyang, China;Department of Information and Communication Engineering, Hoseo University, Asan, South Korea;

关键词: Physical layer security;    non-orthogonal multiple access;    cooperative communication;    relay selection;   

DOI  :  10.1109/ACCESS.2019.2923450

来源: DOAJ

【 摘 要 】

In this paper, we investigate the secrecy outage performance of a typical cooperative downlink non-orthogonal multiple access (NOMA) system over Nakagami-m fading channel, in which the base station transmits a superimposed signal to two users via a relay. First, the secrecy outage behavior of the considered system over Nakagami-$m$ fading channel under three wiretapping cases, e.g., one eavesdropper (Eve), non-colluding and colluding eavesdroppers, are studied, and both analytical and asymptotic expressions for the secrecy outage probability are derived. Next, by considering the availability of Eves' channel state information, we adopt the two-stage relay selection (RS) strategy to improve the system's secrecy outage performance. Finally, simulation results are provided to corroborate the accuracy of our derived expressions. The results show that: 1) there exists secrecy performance floor for cooperative NOMA system, and it was determined by the weak user's secrecy requirement and the channel conditions of the Eves; 2) the two-stage RS scheme can increase the secrecy outage performance significantly under three wiretapping cases; 3) the secrecy performance of cooperative NOMA network is superior to that of orthogonal multiple access network on the condition of low and medium signal-to-noise ratio regions.

【 授权许可】

Unknown