Zaghdoud, NesrineMnaouer, Adel BenAlouane, Wided HadjBoujemaa, HatemTouati, Farid2020-10-012020-10-01© 20202020-06Zaghdoud, N., Mnaouer, A. B., Alouane, W. H., Boujemaa, H., & Touati, F. (2020, June). Secrecy Performance Analysis of Multi-Antenna NOMA System with AF/DF relaying under External and Internal Eavesdropping Scenarios. In 2020 International Wireless Communications and Mobile Computing (IWCMC) (pp. 1726-1732). IEEE. https://doi.org/10.1109/IWCMC48107.2020.9148104978-172813129-0https://doi.org/10.1109/IWCMC48107.2020.9148104http://hdl.handle.net/20.500.12519/249This conference paper is not available at CUD collection. The version of scholarly record of this conference paper is published in 2020 International Wireless Communications and Mobile Computing (IWCMC) (2020), available online at: https://doi.org/10.1109/IWCMC48107.2020.9148104Due to the successive interference cancellation (SIC) technique, Non orthogonal multiple Access (NOMA) users have the capability of decoding the other paired users sharing the same resource bloc. As a result, NOMA technique is not only exposed to external eavesdropping, but also to internal eavesdropping which raises security risks regarding NOMA users' privacy. Therefore, this research aims to analyse a Multi-antenna cooperative NOMA system where both Decode and Forward (DF) and Amplify and Forward (AF) strategies are studied. In this context, we investigate the secrecy performance of our system with both internal and external eavesdropping scenarios. Closed-form expressions of the secrecy outage probability (SOP) and the strictly positive secrecy capacity (SPSC) metrics are derived. Numerical results are given to illustrate the validity of the obtained theoretical results. © 2020 IEEE.enPermission to reuse abstract has been secured from Institute of Electrical and Electronics Engineers Inc.Amplify and ForwardCooperative NOMADecode and Forwardexternal eavesdroppinginternal eavesdroppingMulti-antennasecrecy outage probabilitystrictly positive secrecy capacityAntennasDecodingMobile computingMultiple access interferenceClosed-form expressionMultiple accessNumerical resultsPerformance analysisSecrecy outage probabilitiesSuccessive interference cancellation(SIC)Security systemsConference PaperCopyright : © 2020 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.