TY - JOUR
T1 - Effective Secrecy Rate for a Downlink NOMA Network
AU - Yu, Wenjuan
AU - Chorti, Arsenia
AU - Musavian, Leila
AU - Vincent Poor, H.
AU - Ni, Qiang
N1 - Funding Information:
This work was supported in part by the U.K. Engineering and Physical Sciences Research Council (EPSRC) under Grant EP/N032268/1 and Grant EP/K011693/1, in part by the EU Seventh Framework Programme (FP7) under Grant PIRSES-GA-2013-610524, in part by the Royal Society Project under Grant IEC170324, and in part by the U.S. National Science Foundation under Grant ECCS-1647198 and Grant CNS-1702808.
Funding Information:
Manuscript received June 13, 2018; revised March 29, 2019; accepted August 14, 2019. Date of publication September 6, 2019; date of current version December 10, 2019. This work was supported in part by the U.K. Engineering and Physical Sciences Research Council (EPSRC) under Grant EP/N032268/1 and Grant EP/K011693/1, in part by the EU Seventh Framework Programme (FP7) under Grant PIRSES-GA-2013-610524, in part by the Royal Society Project under Grant IEC170324, and in part by the U.S. National Science Foundation under Grant ECCS-1647198 and Grant CNS-1702808. The associate editor coordinating the review of this article and approving it for publication was Prof. S. Yang. (Corresponding author: Wenjuan Yu.) W. Yu is with the 5G Innovation Centre, Institute for Communication Systems, University of Surrey, Guildford GU2 7XH, U.K. (e-mail: w.yu@surrey.ac.uk).
Publisher Copyright:
© 2002-2012 IEEE.
PY - 2019/12
Y1 - 2019/12
N2 - In this paper, a novel approach is introduced to study the achievable delay-guaranteed secrecy rate, by introducing the concept of the effective secrecy rate (ESR). This study focuses on the downlink of a non-orthogonal multiple access (NOMA) network with one base station, multiple single-antenna NOMA users and an eavesdropper. Two possible eavesdropping scenarios are considered: 1) an internal, unknown, eavesdropper in a purely antagonistic network; and 2) an external eavesdropper in a network with trustworthy peers. For a purely antagonistic network with an internal eavesdropper, the only receiver with a guaranteed positive ESR is the one with the highest channel gain. A closed-form expression is obtained for the ESR at high signal-to-noise ratio (SNR) values, showing that the strongest user's ESR in the high SNR regime approaches a constant value irrespective of the power coefficients. Furthermore, it is shown the strongest user can achieve higher ESR if it has a distinctive advantage in terms of channel gain with respect to the second strongest user. For a trustworthy NOMA network with an external eavesdropper, a lower bound and an upper bound on the ESR are proposed and investigated for an arbitrary legitimate user. For the lower bound, a closed-form expression is derived in the high SNR regime. For the upper bound, the analysis shows that if the external eavesdropper cannot attain any channel state information (CSI), the legitimate NOMA user at high SNRs can always achieve positive ESR, and the value of it depends on the power coefficients. Simulation results numerically validate the accuracy of the derived closed-form expressions and verify the analytical results given in the theorems and lemmas.
AB - In this paper, a novel approach is introduced to study the achievable delay-guaranteed secrecy rate, by introducing the concept of the effective secrecy rate (ESR). This study focuses on the downlink of a non-orthogonal multiple access (NOMA) network with one base station, multiple single-antenna NOMA users and an eavesdropper. Two possible eavesdropping scenarios are considered: 1) an internal, unknown, eavesdropper in a purely antagonistic network; and 2) an external eavesdropper in a network with trustworthy peers. For a purely antagonistic network with an internal eavesdropper, the only receiver with a guaranteed positive ESR is the one with the highest channel gain. A closed-form expression is obtained for the ESR at high signal-to-noise ratio (SNR) values, showing that the strongest user's ESR in the high SNR regime approaches a constant value irrespective of the power coefficients. Furthermore, it is shown the strongest user can achieve higher ESR if it has a distinctive advantage in terms of channel gain with respect to the second strongest user. For a trustworthy NOMA network with an external eavesdropper, a lower bound and an upper bound on the ESR are proposed and investigated for an arbitrary legitimate user. For the lower bound, a closed-form expression is derived in the high SNR regime. For the upper bound, the analysis shows that if the external eavesdropper cannot attain any channel state information (CSI), the legitimate NOMA user at high SNRs can always achieve positive ESR, and the value of it depends on the power coefficients. Simulation results numerically validate the accuracy of the derived closed-form expressions and verify the analytical results given in the theorems and lemmas.
KW - Effective capacity
KW - NOMA
KW - delay-outage probability
KW - secrecy rate
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U2 - 10.1109/TWC.2019.2938515
DO - 10.1109/TWC.2019.2938515
M3 - Article
AN - SCOPUS:85076692265
SN - 1536-1276
VL - 18
SP - 5673
EP - 5690
JO - IEEE Transactions on Wireless Communications
JF - IEEE Transactions on Wireless Communications
IS - 12
M1 - 8826572
ER -