Research project 2016–2021
Wireless-Powered Untrusted Relaying Networks
An early-career research program on physical-layer security for two-way relay networks where the forwarding node is inherently untrusted, exploiting cooperative jamming and wireless energy harvesting to achieve information-theoretic security without additional power infrastructure.
- Role
- Research Assistant
- Supervisors
- Prof. Abbas Mohammadi, Dr. Ali Kuhestani
Overview
This research program examined physical-layer security in cooperative relay networks where the relay is an untrusted amplify-and-forward (AF) node — it is needed to extend coverage yet cannot be allowed to decode the source messages. The work addresses two interconnected problems: (i) characterizing the fundamental security–reliability trade-off (SRT) under this threat model, and (ii) designing cooperative strategies that resolve the tension without external power infrastructure.
The core mechanism couples a cooperative friendly jammer — which transmits artificial noise to degrade the relay’s eavesdropping capability — with wireless energy harvesting (WEH) at the relay, so that jamming energy is simultaneously harvested and recycled to sustain two-way data exchange. Closed-form expressions for secrecy outage probability (SOP) and connection outage probability (COP) are derived under Rayleigh fading, and power allocation is optimised to navigate the SRT. A follow-on study extends the analysis to multi-hop AF chains, establishing conditions under which cascaded untrusted relays can still yield a positive secrecy rate.
Technical Contributions
Milad Tatar Mamaghani, Ali Kuhestani, and Hamid Behroozi, “Can a multi-hop link relying on untrusted amplify-and-forward relays render security?” Wireless Networks, vol. 27, pp. 795–807, Jan. 2021.
Milad Tatar Mamaghani and Robert Abbas, “Security and reliability performance analysis for two-way wireless energy harvesting based untrusted relaying with cooperative jamming,” IET Communications, vol. 13, pp. 449–459, Mar. 2019.
Milad Tatar Mamaghani, Ali Kuhestani, and Kai Kit Wong, “Secure two-way transmission via wireless-powered untrusted relay and external jammer,” IEEE Transactions on Vehicular Technology, vol. 67, no. 9, pp. 8451–8465, Sept. 2018.
Milad Tatar Mamaghani, Abbas Mohammadi, Phil Yeoh, and Ali Kuhestani, “Secure two-way communication via a wireless-powered untrusted relay and friendly jammer,” in Proc. IEEE Global Communications Conference, Singapore, pp. 1–6, Dec. 2017.
Milad Tatar Mamaghani, “Secure Communications via Untrusted Relaying with Wireless Energy Harvesting: Performance Analysis and Trade-offs,” B.Sc. Thesis [in Persian], Department of Electrical Engineering, Amirkabir University of Technology (Tehran Polytechnic), Tehran, Iran, Sep. 2016.