Cooperation for interference management: A GDoF perspective

TL;DR

This paper analyzes how cooperation via relays affects interference management in wireless networks, specifically through the GDoF framework, by deriving new bounds and schemes for the symmetric interference relay channel.

Contribution

It introduces new upper bounds and transmission schemes for the LD-IRC and extends these results to characterize the GDoF of the Gaussian IRC in a specific regime, completing existing literature.

Findings

New upper bounds on sum-capacity of LD-IRC using genie-aided methods

Four novel transmission schemes achieving these bounds

GDoF characterization for Gaussian IRC in the weak interference regime

Abstract

The impact of cooperation on interference management is investigated by studying an elemental wireless network, the so called symmetric interference relay channel (IRC), from a generalized degrees of freedom (GDoF) perspective. This is motivated by the fact that the deployment of relays is considered as a remedy to overcome the bottleneck of current systems in terms of achievable rates. The focus of this work is on the regime in which the interference link is weaker than the source-relay link in the IRC. Our approach towards studying the GDoF goes through the capacity analysis of the linear deterministic IRC (LD-IRC). New upper bounds on the sum-capacity of the LD-IRC based on genie-aided approaches are established. These upper bounds together with some existing upper bounds are achieved by using four novel transmission schemes. Extending the upper bounds and the transmission schemes to the Gaussian case, the GDoF of the Gaussian IRC is characterized for the aforementioned regime. This completes the GDoF results available in the literature for the symmetric GDoF. It is shown that in the strong interference regime, in contrast to the IC, the GDoF is not a monotonically increasing function of the interference level.