Interference Mitigation through Limited Transmitter Cooperation

TL;DR

This paper analyzes the two-user Gaussian interference channel with limited transmitter cooperation, providing a near-optimal capacity region characterization and revealing a reciprocity with receiver cooperation in interference mitigation.

Contribution

It offers the first constant-gap capacity characterization for transmitter cooperation in interference channels and uncovers a fundamental reciprocity with receiver cooperation.

Findings

Capacity region within 6.5 bits/s/Hz of the true capacity.

Reciprocity between transmitter and receiver cooperation scenarios.

Similar benefits of cooperation in interference-limited regimes.

Abstract

Interference limits performance in wireless networks, and cooperation among receivers or transmitters can help mitigate interference by forming distributed MIMO systems. Earlier work shows how limited receiver cooperation helps mitigate interference. The scenario with transmitter cooperation, however, is more difficult to tackle. In this paper we study the two-user Gaussian interference channel with conferencing transmitters to make progress towards this direction. We characterize the capacity region to within 6.5 bits/s/Hz, regardless of channel parameters. Based on the constant-to-optimality result, we show that there is an interesting reciprocity between the scenario with conferencing transmitters and the scenario with conferencing receivers, and their capacity regions are within a constant gap to each other. Hence in the interference-limited regime, the behavior of the benefit brought by transmitter cooperation is the same as that by receiver cooperation.