We demonstrate that the sum-rate capacity of a memoryless Gaussian network at high signal-to-signal ratio (SNR) can be asymptotically doubled when feedback is available. To demonstrate this phenomenon we study two networks: the one-to-two scalar Gaussian broadcast channel (BC) and the twoto-two scalar Gaussian interference channel (IC). For the broadcast channel we show that if the noise sequen...

We establish natural connections between continuous-time Gaussian feedback/memory channels and their associated discrete-time versions in the forms of sampling and approximating theorems. It turns out that these connections, together with relevant tools from stochastic calculus, can enhance our understanding of continuous-time Gaussian channels in terms of giving alternative interpretations to ...

The MIMOME channel is a Gaussian wiretap channel in which the sender, receiver, and eavesdropper all have multiple antennas. We characterize the secrecy capacity as the saddle-value of a minimax problem. Among other implications, our result establishes that a Gaussian distribution maximizes the secrecy capacity characterization of Csiszár and Körner when applied to the MIMOME channel. We also d...