Comments on "Closed-form analysis of linearly constrained CMA-based blind multiuser detector"

We point out that the proof of global convergence of LCCM detector is incorrect in the paper by Tang et al. (see ibid., vol.4, no.9, p.273-76, 2000). According to propositions presented in the paper by Xu and Feng (see Electron. Lett., vol.36, no.2, p.171-72, 2000), we further analyze the conditions for global convergence of LCCM detector, and give the low bound of constraint on the power of desired user.