Interference Channels with Source Cooperation

TL;DR

This paper investigates how source cooperation affects interference management in two-user Gaussian channels, deriving sum-capacity bounds and demonstrating near-optimal coding schemes with full-duplex sources.

Contribution

It introduces a coding scheme based on Han and Kobayashi's superposition method for channels with source cooperation, and establishes new upper bounds on sum-capacity.

Findings

Sum-capacity is characterized within a constant gap.

The same scheme achieves sum-capacity with noiseless feedback.

New upper bounds on sum-capacity are derived.

Abstract

The role of cooperation in managing interference - a fundamental feature of the wireless channel - is investigated by studying the two-user Gaussian interference channel where the source nodes can both transmit and receive in full-duplex. The sum-capacity of this channel is obtained within a gap of a constant number of bits. The coding scheme used builds up on the superposition scheme of Han and Kobayashi (1981) for the two-user interference channel without cooperation. New upperbounds on the sum-capacity are also derived. The same coding scheme is shown to obtain the sum-capacity of the symmetric two-user Gaussian interference channel with noiseless feedback within a constant gap.