Capacity Region of Vector Gaussian Interference Channels with Generally Strong Interference

TL;DR

This paper characterizes the capacity region of vector Gaussian interference channels with generally strong interference, extending the understanding of when interference can be fully decoded for capacity achievement.

Contribution

It introduces the concept of generally strong interference, provides sufficient conditions for such channels, and determines their sum-rate capacity and capacity boundary points.

Findings

Derived sufficient conditions for generally strong interference

Established sum-rate capacity for these channels

Identified capacity region boundary points

Abstract

An interference channel is said to have strong interference if for all input distributions, the receivers can fully decode the interference. This definition of strong interference applies to discrete memoryless, scalar and vector Gaussian interference channels. However, there exist vector Gaussian interference channels that may not satisfy the strong interference condition but for which the capacity can still be achieved by jointly decoding the signal and the interference. This kind of interference is called generally strong interference. Sufficient conditions for a vector Gaussian interference channel to have generally strong interference are derived. The sum-rate capacity and the boundary points of the capacity region are also determined.