Capacity of Gaussian MIMO Bidirectional Broadcast Channels

TL;DR

This paper determines the capacity region of the Gaussian MIMO bidirectional broadcast channel, a key component in relay-based two-phase communication networks, enhancing understanding of spectral efficiency in such systems.

Contribution

It provides the first explicit characterization of the capacity region for Gaussian MIMO bidirectional broadcast channels, advancing theoretical knowledge in relay communication systems.

Findings

Capacity region characterized for Gaussian MIMO bidirectional broadcast channels

Theoretical bounds for spectral efficiency established

Framework for optimizing relay-based bidirectional communication

Abstract

We consider the broadcast phase of a three-node network, where a relay node establishes a bidirectional communication between two nodes using a spectrally efficient two-phase decode-and-forward protocol. In the first phase the two nodes transmit their messages to the relay node. Then the relay node decodes the messages and broadcasts a re-encoded composition of them in the second phase. We consider Gaussian MIMO channels and determine the capacity region for the second phase which we call the Gaussian MIMO bidirectional broadcast channel.