Secrecy outage of SWIPT in the presence of cooperating eavesdroppers

This work investigates the secrecy performance of a simultaneous wireless information and power transfer system that operates in the presence of cooperating eavesdroppers. The multi-antenna access point's transmission is used for information-decoding by a multi-antenna node and for energy-harvesting (EH) by multiple single-antenna nodes. However, some of the nodes authorized for EH only attempt to eavesdrop on the ongoing information transmission by utilizing a generalized on-off power splitting architecture. We derive a closed-form expression for the secrecy outage probability of the considered Multiple-Input-Multiple-Output Multiple-Eavesdroppers system. Theoretical and simulation results are provided to validate the derived results.