On the Performance of Security-Based Nonorthogonal Multiple Access in Coordinated Multipoint Networks

Yue Tian,Zhanwei Wang,Xianling Wang

doi:10.1155/2018/8921895

Abstract

The conventional nonorthogonal multiple access (NOMA) strategy has secrecy challenge in coordinated multipoint (CoMP) networks. Under the secrecy considerations, this paper focuses on the security-based NOMA system, which aims to improve the physical layer security issues of conventional NOMA in the coordinated multipoint (NOMA-CoMP) networks. The secrecy performance of S-NOMA in CoMP, that is, the secrecy sum-rate and the secrecy outage probability, is analysed. In contrast to the conventional NOMA (C-NOMA), the results show that the proposed S-NOMA outperforms C-NOMA in terms of the secrecy outage probability and security-based effective sum-rate.

Highlights

As a promising candidate for the multiple access schemes in the fifth-generation (5G) mobile system, nonorthogonal multiple access (NOMA) has received widespread attention [1]
In contrast to the conventional NOMA (C-NOMA), we show that the proposed security-based NOMA (S-NOMA) outperforms C-NOMA in terms of the secrecy outage probability and security-based effective sumrate
In contrast to the C-NOMA, the S-NOMA strategy reduces the leakage of information to the untrusted users; the secrecy capacity of S-NOMA is more close to the upper bond capacity, so S-NOMA has a better performance than C-NOMA in terms of secrecy outage probability and secrecy effective sumrate

Summary

Introduction

As a promising candidate for the multiple access schemes in the fifth-generation (5G) mobile system, nonorthogonal multiple access (NOMA) has received widespread attention [1]. It should be noted that, due to the fact that the multiple users’ signals in NOMA are sharing the same resource channels, the NOMA-CoMP network is confronted with a security issue; that is, the eavesdroppers in the NOMACoMP network could listen to the legal users’ messages, which creates a secrecy challenge in the physical layer communications. Reference [19] investigated the physical layer security of NOMA in the large-scale networks; the authors showed that the security issues of NOMA can be alleviated by generating a protected zone for the legal users and by creating artificial noise at the transmitters. To enhance the physical layer security of NOMA-CoMP system, we proposed a security-based NOMA (S-NOMA) strategy, which combines the coordinated user-scheduling strategy and minimise-information-leakage-based joint transmission strategy in the downlink of a CoMP network. In contrast to the conventional NOMA (C-NOMA), we show that the proposed S-NOMA outperforms C-NOMA in terms of the secrecy outage probability and security-based effective sumrate

System Model

Security-Based NOMA Strategy in CoMP Networks

Performance Analysis of S-NOMA in CoMP Network

Performance Evaluation

Conclusion