  The joint design of beamforming vector and artificial noise covariance matrix
is investigated for multiple-input-single-output-multiple-eavesdropper
simultaneous wireless information and power transferring (MISOME-SWIPT)
systems. A secrecy energy efficiency (SEE) maximization problem is formulated
in the MISOME-SWIPT system with imperfect channel state information and
proportional secrecy rate constraints. Since the formulated SEE maximization
problem is non-convex, it is first recast into a series of convex problems in
order to obtain the optimal solution with a reasonable computational
complexity. Numerical results are used to verify the performance of the
proposed algorithm and to reveal practical insights.
