Achievable Degrees of Freedom of the K-user Interference Channel with Partial Cooperation

TL;DR

This paper investigates the maximum degrees of freedom in a K-user interference channel with partial cooperation, proposing a new interference alignment scheme that achieves the theoretical outer bound for specific cases.

Contribution

It introduces a signal space-based interference alignment scheme and the Successive Interference Alignment (SIA) algorithm for partial cooperation scenarios.

Findings

Achieves the outer bound of degrees of freedom for K=M+2 cases.

Proposes a novel SIA algorithm for decoding in cooperative interference channels.

Demonstrates the effectiveness of the scheme through theoretical analysis.

Abstract

In this paper, we consider the K-user interference channel with partial cooperation, where a strict subset of the K users cooperate. For the K-user interference channel with cooperating subsets of length M, the outer bound of the total degrees of freedom is KM/(M+1). In this paper, we propose a signal space-based interference alignment scheme that proves the achievability of these degrees of freedom for the case K=M+2. The proposed scheme consists of a design for the transmit precoding matrices and a processing algorithm which we call the Successive Interference Alignment (SIA) algorithm. The decoder of each message uses the SIA algorithm to process the signals received by the M cooperating receivers in order to get the maximum available degrees of freedom.