Robust secure transmission for multiuser MISO systems with probabilistic QoS constraints

• DOI: 10.1007/s11432-015-5342-6
• Publication Date: 2016-01-07T04:15:30Z
• Authors: Lijian Zhang; Liang Jin; Wenyu Luo; Chunming Wang; Yanqun Tang
• Keywords: Artificial Noise; Transmitter power output

This paper considers a unicast multiuser multiple-input single-output (MISO) downlink system overheard by multiple single-antenna eavesdroppers. The objective is to jointly design the beamforming vectors and the artificial noise (AN) covariance matrix with imperfect channel state information (CSI) at the transmitter, such that the total transmit power is minimized while satisfying probabilistic quality of service (QoS) constraints at legitimate users and the eavesdroppers. Using Bernstein-type inequalities and the S-procedure, we recast the non-convex power minimization problem as two different convex semidefinite programs (SDPs) which can be solved using interior-point methods. Simulation results show that the proposed methods outperform a nonrobust method and the ones using the isotropic AN.