Comments on “Precoding and Artificial Noise Design for Cognitive MIMOME Wiretap Channels”

Several gaps and errors in “Precoding Artificial Noise Design for Cognitive MIMOME Wiretap Channels” by Fang et al. are identified corrected. While accommodating these corrections, a rigours proof is given that the successive convex approximation algorithm of secrecy rate maximization (SRM) does generate an increasing bounded sequence true rates hence converges. It further shown its convergence point KKT original SRM problem and, if convex, this globally-optimal, which not necessarily case general. An interlacing property sequences approximate established.