Enabling Relaying Over Heterogeneous Backhauls in the Uplink of Wireless Femtocell Networks

TL;DR

This paper introduces a novel interference management strategy for uplink femtocell networks that uses rate-splitting and game theory to significantly improve throughput and reduce delays without requiring cross-tier cooperation.

Contribution

It proposes a new rate-splitting technique combined with a game-theoretic approach for uplink interference management in heterogeneous femtocell networks, enabling relaying over diverse backhauls.

Findings

Up to 125% rate improvement with wired backhaul

Up to 150% rate improvement with wireless backhaul

Delay reductions up to 2x (wired) and 10x (wireless)

Abstract

In this paper, we develop novel two-tier interference management strategies that enable macrocell users (MUEs) to improve their performance, with the help of open-access femtocells. To this end, we propose a rate-splitting technique using which the MUEs optimize their uplink transmissions by dividing their signals into two types: a coarse message that is intended for direct transmission to the macrocell base station and a fine message that is decoded by a neighboring femtocell and subsequently relayed over a heterogeneous (wireless/wired) backhaul. For deploying the proposed technique, we formulate a non-cooperative game between the MUEs in which each MUE can decide on its relaying femtocell while maximizing a utility function that captures both the achieved throughput and the expected backhaul delay. Simulation results show that the proposed approach yields up to 125% rate improvement and up to 2 times delay reduction with wired backhaul and, 150% rate improvement and up to 10 times delay reduction with wireless backhaul, relative to classical interference management approaches, with no cross-tier cooperation.