Operational Region of D2D Communications for Enhancing Cellular Network Performance

TL;DR

This paper characterizes the conditions under which device-to-device (D2D) communications improve cellular network performance, providing a mathematical framework to identify when D2D is beneficial across various operational scenarios.

Contribution

It introduces a stochastic geometry-based method to determine the operational region where D2D enhances user rates, including a closed-form expression for heavy loaded networks.

Findings

D2D can improve performance beyond proximal communication scenarios.

The operational region depends on parameters like user density and D2D link distance.

D2D benefits are achievable under a wide range of conditions.

Abstract

An important enabler towards the successful deployment of any new element/feature to the cellular network is the investigation and characterization of the operational conditions where its introduction will enhance performance. Even though there has been significant research activity on the potential of device-to-device (D2D) communications, there are currently no clear indications of whether D2D communications are actually able to provide benefits for a wide range of operational conditions, thus justifying their introduction to the system. This paper attempts to fill this gap by taking a stochastic geometry approach on characterizing the set (region) of operational conditions for which D2D communications enhance performance in terms of average user rate. For the practically interesting case of a heavy loaded network, the operational region is provided in closed form as a function of a variety of parameters such as maximum D2D link distances and user densities, reflecting a wide range of operational conditions (points). It is shown that under the appropriate deployment scheme, D2D communications can indeed be beneficial not only for the usually considered regime of "proximal communications" but to a wide range of operational conditions that include D2D link distances comparable to the distance to the cellular access point and considerably large user densities.