Diversity-Multiplexing tradeoff of the Two-User Interference Channel

TL;DR

This paper characterizes the fundamental diversity-multiplexing tradeoff of the two-user Gaussian interference channel and shows that multilevel superposition coding schemes universally achieve this tradeoff.

Contribution

It provides the first complete characterization of the DMT for the two-user interference channel and demonstrates the optimality of multilevel superposition coding schemes.

Findings

Multilevel superposition coding universally achieves the DMT.

Han-Kobayashi scheme achieves the symmetric DMT.

The DMT characterization holds for all fading statistics.

Abstract

Diversity-Multiplexing tradeoff (DMT) is a coarse high SNR approximation of the fundamental tradeoff between data rate and reliability in a slow fading channel. In this paper, we characterize the fundamental DMT of the two user single antenna Gaussian interference channel. We show that the class of multilevel superposition coding schemes universally achieves (for all fading statistics) the DMT for the two-user interference channel. For the special case of symmetric DMT, when the two users have identical rate and diversity gain requirements, we characterize the DMT achieved by the Han-Kobayashi scheme, which corresponds to two level superposition coding.