Secrecy Outage Probability of Relay Selection Based Cooperative NOMA for IoT Networks

Hui Li,Varun G Menon,Mingfu Zhu,Dinh-Thuan Do,Jiangfeng Sun,Shynu P G,Yaping Chen

doi:10.1109/access.2020.3047136

Abstract

As an important partner of fifth generation (5G) communication, the internet of things (IoT) is widely used in many fields with its characteristics of massive terminals, intelligent processing, and remote control. In this paper, we analyze security performance for the cooperative non-orthogonal multiple access (NOMA) networks for IoT, where the multi-relay Wyner model with direct link between the base station and the eavesdropper is considered. In particular, secrecy outage probability (SOP) for two kinds of relay selection (RS) schemes (i.e., single-phase RS (SRS) and two-phase RS (TRS)) is developed in the form of closed solution. As a benchmark for comparison, the SOP for random RS (RRS) is also obtained. To gain more meaningful insights, approximate derivations of SOP under the high signal-to-noise ratio (SNR) region are provided. Results of statistical simulation confirm the theoretical analysis and testify that: i) Compared with RRS scheme, SRS and TRS may improve secure performance because of obtaining smaller SOPs; ii) There exists secrecy performance floor for the SOP in strong SNR regime, which is dominated by NOMA protocol; iii) The security performance can be enhanced by augmenting the quantity of relays for SRS and TRS strategies. The purpose of this work is to provide theoretical basis for the analysis and design of anti-eavesdropping for NOMA systems in IoT.

Highlights

The rapid development of IoT makes all walks of life get convenient and fast services
By comparing asymptotic SOP under RRS scheme with SRS and TRS schemes, we find that the SRS and TRS schemes prominently improve the secrecy outage performance, and the interesting discovery is that increasing the amount of relays can further enhance the security performance
The simulation results show that the security requirements of the nearby user D1 have no effect on the security performance layer, which proves the conclusion of the approximate SOP analyzed in the previous discussion

Summary

Introduction

The rapid development of IoT makes all walks of life get convenient and fast services. Due to the importance of ownership and privacy protection, the IoT system must provide corresponding security mechanisms. The classical method to deal with the security problem is complex encryption and decryption scheme [1]. The terminals of IoT are often limited in size and power, and do not have strong computing power. These contradictions lead that the classical method is not so effective in many scenarios [2].

Objectives

Results

Conclusion