Novel Outer Bounds and Capacity Results for the Interference Channel with Conferencing Receivers

TL;DR

This paper develops new capacity outer bounds for the two-user interference channel with conferencing receivers, leading to novel capacity results and demonstrating the benefits of receiver cooperation strategies.

Contribution

It introduces novel outer bounds for interference channels with conferencing receivers and proves new capacity results under various interference regimes.

Findings

Outer bounds are tighter than previous results.

Both interference mitigation strategies improve capacity.

New capacity results for strong and mixed interference regimes.

Abstract

In this paper, capacity bounds for the two-user Interference Channel (IC) with cooperative receivers via conferencing links of finite capacities is investigated. The capacity results known for this communication scenario are limited to a very few special cases of the one-sided IC. One of the major challenges in analyzing such cooperative networks is how to establish efficient capacity outer bounds for them. In this paper, by applying new techniques, novel capacity outer bounds are presented for the ICs with conferencing users. Using the outer bounds, several new capacity results are proved for interesting channels with unidirectional cooperation in strong and mixed interference regimes. A fact is that the conferencing link (between receivers) may be utilized to provide one receiver with information about its corresponding signal or its non-corresponding signal (interference signal). As a remarkable consequence, it is demonstrated that both strategies can be helpful to achieve the capacity of the channel. Finally, for the case of Gaussian IC, it is mathematically shown that our outer bound is strictly tighter than the previous one derived by Wang and Tse.