Impact of Wireless Energy Transfer Strategies on the Secrecy Performance of Untrustworthy Relay Networks
This work investigates the secrecy outage performance of a dual-hop relaying network with an untrustworthy energy-constrained amplify-and-forward relay. A destination-based jamming technique is adopted in order to prevent the relay from decoding confidential messages from the source. Additionally three time switching-based wireless energy transfer strategies are investigated for supplying power to the relay. For these three strategies we derive simple closed-form asymptotic expressions for the secrecy outage probability at high signal-to-noise ratio. Moreover we provide analytical expressions for the optimum power allocation factor for the information transmission phase. Finally Monte Carlo simulations are carried out to verify the theoretical results through different illustrative cases.