A Counterexample to Cover's 2P Conjecture on Gaussian Feedback Capacity
arXiv:cs/0511019 · doi:10.1109/TIT.2006.878167
Abstract
We provide a counterexample to Cover's conjecture that the feedback capacity $C_\textrm{FB}$ of an additive Gaussian noise channel under power constraint $P$ be no greater than the nonfeedback capacity $C$ of the same channel under power constraint $2P$, i.e., $C_\textrm{FB}(P) \le C(2P)$.
2 pages, submitted to IEEE Transactions on Information Theory