Physical layer security in cognitive NOMA sensor networks with full-duplex technique

Zhihui Shang,Liwei Tao,Tao Zhang,Zhongwu Xiang,Weiwei Yang

doi:10.1177/15501477211059097

Abstract

This article studies the physical layer security in a downlink full-duplex cognitive non-orthogonal multiple access sensor networks (FD-C-NOMA). Compared with the existing works, this article proposes a FD-C-NOMA transmission scheme with a primary user (PU) and secondary user (SU) sensor nodes in the presence of an eavesdropper. The zero-forcing beamforming design problems of FD operation are investigated subject to the practical secrecy rate and the quality of services of PU. To characterize the security reliability trade-off of the FD-C-NOMA scheme, we first derive the closed-form expressions of connection outage probability (COP), the secrecy outage probability (SOP), and effective secrecy throughput (EST) of each SU in the NOMA networks. Then the impacts of the system parameters on the COP, SOP, and EST are investigated to evaluate the security and reliability in the FD-C-NOMA networks. Furthermore, in order to further verify the security and reliability of our considered network, an OMA scheme of FD operation is provided in the simulation for the purpose of comparison. Results demonstrate that the NOMA-based cognitive sensor networks of FD operation outperforms the OMA system in terms of EST. Finally, simulations are performed to validate the accuracy of our analysis results of the proposed scheme.

Highlights

The generation wireless sensor networks call for advanced communication techniques that can achieve high spectrum efficiency (SE) and improve user throughput in support of the demand for high data rates bring by the increasing number of mobile devices.[1,2]
We derive the closed-form expressions (CFEs) of the connection outage probability (COP), the secrecy outage probability (SOP), and effective secrecy throughput (EST) of secondary user transmission link in the proposed secure FDC-non-orthogonal multiple access (NOMA) scheme over Rayleigh fading channels, which show that pairing user N and user M sensor nodes with best power allocation can achieve better performance
Our results show that the COP decreases as signal-to-noise ratio (SNR) increases, but an outage floor will appear in the high SNR regime, which demonstrates that Pt is constrained by interference threshold Q

Summary

Introduction

The generation wireless sensor networks call for advanced communication techniques that can achieve high spectrum efficiency (SE) and improve user throughput in support of the demand for high data rates bring by the increasing number of mobile devices.[1,2] Cognitive radio (CR) and non-orthogonal multiple access (NOMA) constitute promising techniques of achieving high SE.[3,4] To take full advantage of SE, cognitive sensor networks (CSNs) allow the unlicensed secondary user sensor nodes (SUs) operating on the spectrum reserved for the licensed primary user. The principal contributions of our article are summarized as follows: We newly design a FD-C-NOMA scheme for enhancing secrecy performance of SUs through properly dealing with directional jamming, where SUs network share the same licensed spectrum with the cognitive PU network.[28,29,30,31] In addition, the concurrent transmission of signals in a NOMA manner will increase the risk of information leakage, so that different ZFB schemes will be designed at the FD sensor node in different transmission phases to transmit directional jamming signals to Eve while guaranteeing the QoS requirements of the PU to enhance the SU’s security. We derive the closed-form expressions (CFEs) of the connection outage probability (COP), the secrecy outage probability (SOP), and effective secrecy throughput (EST) of secondary user transmission link in the proposed secure FDC-NOMA scheme over Rayleigh fading channels, which show that pairing user N and user M sensor nodes with best power allocation can achieve better performance.

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Findings

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