Ignacio Berberana

LTE-advanced: an operator perspective

LTE-Advanced extends the capabilities originally developed in LTE within the 3GPP. Carrier aggregationis the most significant, albeit complex, improvement provided by LTE-Advanced. Bandwidths from various portions of the spectrum are logically concatenated resulting in a virtual block of a much larger band, enabling increased data throughput. Additionally, enhancements to MIMO antenna techniques in the uplink and downlink further increase the data throughput. Cell coverage is improved by means of relay nodes, which connect to donor eNode-Bs. To cope with the many varieties of cell types and sizes (macro, pico, femto), intercell interference control is enhanced to handle these heterogeneous networks. Operators hope to leverage LTE-Advanced to offer their mobile wireless customers a vastly superior user experience.

Benefits and challenges of virtualization in 5G radio access networks

Future 5G deployments will embrace a multitude of novel technologies that will significantly change the air interface, system architecture, and service delivery platforms. However, compared to previous migrations to next-generation technologies, this time the implementation of mobile networks will receive particular attention. The virtualization of network functionality, the application of open, standardized, and inter-operable software, as well as the use of commodity hardware, will transform mobile-network technology. In this article we focus on the benefits, challenges, and limitations that accompany virtualization in 5G radio access networks (RANs). Within the context of virtualized RAN, we consider its implementation requirements and analyze its cost. We also outline the impact on standardization, which will continue to involve 3GPP but will engage new players whose inclusion in the discussion encourages novel implementation concepts.

Energy Efficiency and Performance in mobile networks deployments with femtocells

The new generations of cellular technologies and the current trend towards small cells or femtocells, will offer an improved spectral efficiency per area, but they also offer an opportunity to improve the energy efficiency, measured as the power consumption needed to provide a certain throughput in a given area. In this paper, two network performance indicators, aggregated throughput and energy efficiency, have been analyzed and compared in two network architectures; a traditional deployment based on outdoor macro base stations, for the provision of outdoor and indoor coverage, and a deployment where some of the indoor traffic is supported by femtocells. Performance simulations and energy calculations have shown that the introduction of a femtocell layer, complementing the macrocell layer is a great leap forward in system performance and energy efficiency, when compared with current indoor coverage based on outdoor macro and micro base stations. Additionally, this paper present a study on how much could be reduced the mobile network energy requirements of macrocell deployments in high density urban deployments, in low traffic conditions, based on the application of two Self Organizing Networks (SON) techniques for energy saving, selective disconnection and power reduction of eNodeBs and HeNBs.

An adaptive 5G multiservice and multitenant radio access network architecture

This article provides an overview on objectives and first results of the Horizon 2020 project 5G NOvel Radio Multiservice adaptive network Architecture 5GNORMA. With 5G NORMA, leading players in the mobile ecosystem aim to underpin Europes leadership position in 5G. The key objective of 5G NORMA is to develop a conceptually novel, adaptive and future-proof 5G mobile network architecture. This architecture will allow for adapting the network to a wide range of service specific requirements, resulting in novel service-aware and context-aware end-to-end function chaining. The technical approach is based on an innovative concept of adaptive decomposition and allocation of mobile network functions based on end-user requirements and infrastructure capabilities. At the same time, cost savings and faster time to market are to be expected by joint deployment of logically separated multiservice and multitenant networks on common hardware and other physical resources making use of traffic multiplexing gains. In this context architectural enablers such as network function virtualization and software-defined mobile networking will play a key role for introducing the needed flexible resource assignment to logical networks and specific virtual network functions. Copyright

Wireless-Optical Network Convergence: Enabling the 5G Architecture to Support Operational and End-User Services

This article presents a converged 5G network infrastructure and an overarching architecture to jointly support operational network and end-user services, proposed by the EU 5G PPP project 5G-XHaul. The 5G-XHaul infrastructure adopts a common fronthaul/backhaul network solution, deploying a wealth of wireless technologies and a hybrid active/passive optical transport, supporting flexible fronthaul split options. This infrastructure is evaluated through a novel modeling. Numerical results indicate significant energy savings at the expense of increased end-user service delay.

5G-XHaul: a converged optical and wireless solution for 5G transport networks

The common European Information and Communications Technology sector vision for 5G is that it should leverage on the strengths of both optical and wireless technologies. In the 5G context, a wide spectra of radio access technologies-such as millimetre wave transmission, massive multiple-input multiple-output and new waveforms-demand for high capacity, highly flexible and convergent transport networks. As the requirements imposed on future 5G networks rise, so do the challenges in the transport network. Hence, 5G-XHaul proposes a converged optical and wireless transport network solution with a unified control plane based on software defined networking. This solution is able to support the flexible backhaul and fronthaul-X-Haul-options required to tackle the future challenges imposed by 5G radio access technologies. 5G-XHaul studies the trade-offs involving fully or partially converged backhaul and fronthaul functions, with the aim of maximising the associated sharing benefits, improving efficiency in resource utilisation and providing measurable benefits in terms of overall cost, scalability and sustainability. Copyright

5G infrastructures supporting end-user and operational services: The 5G-XHaul architectural perspective

We propose an optical-wireless 5G infrastructure offering converged fronthauling/backhauling functions to support both operational and end-user cloud services. A layered architectural structure required to efficiently support these services is shown. The data plane performance of the proposed infrastructure is evaluated in terms of energy consumption and service delay through a novel modelling framework. Our modelling results show that the proposed architecture can offer significant energy savings but there is a clear trade-off between overall energy consumption and service delay.

Benefits and Challenges of Cloud Technologies for 5G Architecture

This paper focuses on the practical implementation of a Cloud-RAN architecture in the context of future 5G systems, with particular emphasis on different aspects of the functional split between the cloud platform and the radio access points. First, we provide a comprehensive overview of implementation aspects and how different hardware options impact the implementation of RAN functionality. We further discuss a virtualized infrastructure which may have a significant impact on how algorithms are implemented, how they interact with each other, and how they can be scaled within the RAN. We also analyze implementation constraints to be considered to provide backwards compatibility with 3GPP LTE; such constraints on the computing platforms result from the RAN requirements in terms of latency and throughput. Finally, the level of flexibility achievable by the proposed architecture is described from a practical point of view.

Telecom I+D03 - SON Use Case Study “Energy Saving” for LTE eNBs

The 3GPP is defining a next generation radio access network called LTE (Long Term Evolution), which introduces several improvements respect current mobile systems, one of them are self-organization and self-optimization functions (SON) in base stations (eNB) and OM subsystem, that suppose a considerable increase on the network “intelligence”. This paper discusses the application of a SON function, Energy Saving, and evaluates the energy savings and system performance, when applied. To illustrate the effect of the energy saving techniques, several simulations have been carried out with a radio-planning tool in a real mobile network deployment. Two technical approaches have been followed: switching off cells and reducing the eNB transmitted power (TXP). For both approaches a reference scenario with 18 eNBs (with 54 cells) has been selected. This scenario reflects a dense urban area with a Manhattan like distribution, in an area of 2 km × 2 km, with an average ISD of 250 m. A 2×2 MIMO antenna configuration has been used in all simulations. eNBs transmitted power was 46 dBm, the operation frequency was 2 GHz and the bandwidth was 5 MHz. The Energy Saving is a promising SON Use Case that allows decreasing operators energy costs, carbon footprint, and the radiation emitted by fixed infrastructure of the mobile telephony systems, such as base stations antennas.

SDN-based joint backhaul and access design for efficient network layer operations

Small cell networks have been broadly regarded as an imperative evolution path for the next-generation cellular networks. Dense small cell deployments will be connected to the core network by heterogeneous backhaul technologies such as fiber, microwave, high frequency wireless solutions, etc., which have their inherent limitations and impose big challenges on the operation of radio access network to meet the increasing rate demands in future networks. To address these challenges, this paper presents an efficient design considered in the iJOIN (Interworking and JOINt Design of an Open Access and Backhaul Network Architecture for Small Cells based on Cloud Networks) project with the objective of jointly optimizing backhaul and radio access network operations through the adoption of SDN (Software Defined Networking). Furthermore, based on this framework, the implementation of several intelligent management functions, including mobility management, network-wide energy optimization and data center placement, is demonstrated.