New Outer Bounds on the Capacity Region of Gaussian Interference Channels

TL;DR

This paper extends outer bounds on the capacity region of Gaussian interference channels to multiple users with asymmetric parameters, demonstrating that simple detection strategies can achieve capacity in low-power scenarios.

Contribution

It generalizes existing bounds to m-user channels with asymmetry and shows that treating interference as noise is optimal in certain low-power conditions.

Findings

Outer bounds are extended to m-user channels.

Single-user detection achieves capacity in low-power regimes.

Treating interference as noise incurs no performance loss.

Abstract

Recent outer bounds on the capacity region of Gaussian interference channels are generalized to $m$-user channels with $m>2$ and asymmetric powers and crosstalk coefficients. The bounds are again shown to give the sum-rate capacity for Gaussian interference channels with low powers and crosstalk coefficients. The capacity is achieved by using single-user detection at each receiver, i.e., treating the interference as noise incurs no loss in performance.