Interference Decoding for Deterministic Channels

TL;DR

This paper introduces an interference decoding inner bound for deterministic interference channels with three user pairs, which is tight under strong interference and outperforms traditional interference-as-noise approaches.

Contribution

It presents a novel interference decoding inner bound that includes interference alignment and extends to noisy channels, improving capacity region estimates.

Findings

Inner bound tight under strong interference

Outperforms interference-as-noise bounds

Generalizes to noisy output channels

Abstract

An inner bound to the capacity region of a class of deterministic interference channels with three user pairs is presented. The key idea is to simultaneously decode the combined interference signal and the intended message at each receiver. It is shown that this interference-decoding inner bound is tight under certain strong interference conditions. The inner bound is also shown to strictly contain the inner bound obtained by treating interference as noise, which includes interference alignment for deterministic channels. The gain comes from judicious analysis of the number of combined interference sequences in different regimes of input distributions and message rates. Finally, the inner bound is generalized to the case where each channel output is observed through a noisy channel.