On Secure Beamforming for Wiretap Channels with Partial Channel State Information at the Transmitter
In this paper, the authors consider the secure transmission in ergodic fast fading Multiple-Input Single-Output Single-antenna-Eavesdropper (MISOSE) wiretap channels with only the statistics of eavesdropper's Channel State Information at the Transmitter (CSIT). Two kinds of the legitimate CSIT are assumed, that is, full and statistical legitimate CSIT. With full legitimate CSIT, they generalize and optimize the previously proposed Artificial Noise (AN) aided secure beam-forming to improve its secrecy rate performance. The AN covariance matrix in their scheme is more flexible than previous scheme and the region of non-zero secrecy rate is enlarged significantly according to their simulations.