In this paper, we investigate a robust secrecy transmission design for a multiple-input multiple-output simultaneous wireless information and power transfer system. Specifically, considering time switching at the transmitter, we aim to maximize the outage secrecy rate by jointly designing the information signal, energy signal, and time switching ratio, under the constraints of transmit power and harvested energy. The formulated problem is highly non-convex due to the difference of two log-det functions and probabilistic constraints. To overcome this obstacle, we divide the original problem into three convex subproblems. Then, an alternative optimization method is proposed. Finally, numerical results are presented to verify the performance of the proposed scheme.
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