Bruno Melis

Fronthaul and backhaul requirements of flexibly centralized radio access networks

Cloud radio access networks promise considerable benefits compared to decentralized network architectures, but they also put challenging requirements on the fronthaul and backhaul network. Flexible centralization can relax these requirements by adaptively assigning different parts of the processing chain to either the centralized baseband processors or the base stations based on the load situation, user scenario, and availability of fronthaul links. In this article, we provide a comprehensive overview of different functional split options and analyze their specific requirements. We compare these requirements to available fronthaul technologies, and discuss the convergence of fronthaul and backhaul technologies. By evaluating the aggregated fronthaul traffic, we show the benefits of flexible centralization and give guidelines on how to set up the fronthaul network to avoid over- or under-dimensioning.

Heterogeneous Backhaul for Cloud-Based Mobile Networks

To meet the increasing capacity demands of future mobile networks, dense deployment of radio access nodes in combination with partly centralized processing by means of a cloud-based architecture is a promising option. In such an architecture, the design and optimization of the backhaul plays a crucial role. In this paper, we review different backhaul technologies available and discuss their characteristics for use in cloud-based networks. We point out how a heterogeneous backhaul network and a flexible centralization enables the proposed architecture and give an outlook on how a joint design of access and backhaul can help in meeting the increased demands.