1,403 research outputs found
Architectures and Key Technical Challenges for 5G Systems Incorporating Satellites
Satellite Communication systems are a promising solution to extend and
complement terrestrial networks in unserved or under-served areas. This aspect
is reflected by recent commercial and standardisation endeavours. In
particular, 3GPP recently initiated a Study Item for New Radio-based, i.e., 5G,
Non-Terrestrial Networks aimed at deploying satellite systems either as a
stand-alone solution or as an integration to terrestrial networks in mobile
broadband and machine-type communication scenarios. However, typical satellite
channel impairments, as large path losses, delays, and Doppler shifts, pose
severe challenges to the realisation of a satellite-based NR network. In this
paper, based on the architecture options currently being discussed in the
standardisation fora, we discuss and assess the impact of the satellite channel
characteristics on the physical and Medium Access Control layers, both in terms
of transmitted waveforms and procedures for enhanced Mobile BroadBand (eMBB)
and NarrowBand-Internet of Things (NB-IoT) applications. The proposed analysis
shows that the main technical challenges are related to the PHY/MAC procedures,
in particular Random Access (RA), Timing Advance (TA), and Hybrid Automatic
Repeat reQuest (HARQ) and, depending on the considered service and
architecture, different solutions are proposed.Comment: Submitted to Transactions on Vehicular Technologies, April 201
Smart Beamforming for Direct Access to 5G-NR User Equipment from LEO Satellite at Ka-Band
Study how spatial diversity can help in massive IoT and develp signal processing access for MIMO beamformingNon-Terrestrial Networks (NTN), in particular LEO Satellite Networks, are expected to play a key role in extending and complementing terrestrial 5G networks in order to provide services to air, sea and un-served or under-served areas. This work proposes the implementation of a novel scheme called Resource Sharing Beamforming Access (RSBA), which seems a promising solution to deal with scenarios where Bit Error Rate (BER), probability of collision and/or achievable rate are important aspects of study. Given the system architecture presented in this work, RSBA will be proposed as solution in the 5G-NR Sat-IoT scenario. As it is expected, a huge amount of IoT devices will be transmitting in the uplink, and being the case of Non-Orthogonal-Multiple-Access (NOMA), the risk of collisions between devices will increase. The idea, after assessing the channel impairments of a direct link between a LEO Satellite and a NB-IoT device, it to study how spatial diversity via smart beamforming at the receiver will reduce the probability of collision between the devices, and thus increasing the number of users that can access to the media
Design of cellular, satellite, and integrated systems for 5G and beyond
5G AgiLe and fLexible integration of SaTellite And cellulaR (5G-ALLSTAR) is a Korea-Europe (KR-EU) collaborative project for developing multi-connectivity (MC) technologies that integrate cellular and satellite networks to provide seamless, reliable, and ubiquitous broadband communication services and improve service continuity for 5G and beyond. The main scope of this project entails the prototype development of a millimeter-wave 5G New Radio (NR)-based cellular system, an investigation of the feasibility of an NR-based satellite system and its integration with cellular systems, and a study of spectrum sharing and interference management techniques for MC. This article reviews recent research activities and presents preliminary results and a plan for the proof of concept (PoC) of three representative use cases (UCs) and one joint KR-EU UC. The feasibility of each UC and superiority of the developed technologies will be validated with key performance indicators using corresponding PoC platforms. The final achievements of the project are expected to eventually contribute to the technical evolution of 5G, which will pave the road for next-generation communications
From 5G to 6G: Revolutionizing Satellite Networks through TRANTOR Foundation
5G technology will drastically change the way satellite internet providers
deliver services by offering higher data speeds, massive network capacity,
reduced latency, improved reliability and increased availability. A
standardised 5G ecosystem will enable adapting 5G to satellite needs. The
EU-funded TRANTOR project will seek to develop novel and secure satellite
network management solutions that allow scaling up heterogeneous satellite
traffic demands and capacities in a cost-effective and highly dynamic way.
Researchers also target the development of flexible 6G non-terrestrial access
architectures. The focus will be on the design of a multi-orbit and multi-band
antenna for satellite user equipment (UE), as well as the development of gNodeB
(gNB) and UE 5G non-terrestrial network equipment to support
multi-connectivity
On Enhancing Reliability in B5G NTNs with Packet Duplication via Multi-Connectivity
Non-Terrestrial Networks (NTNs) can be used to provide ubiquitous 5G and
beyond services to un(der)served areas. To ensure reliable communication in
such networks, packet duplication (PD) through multi-connectivity is a
promising solution. However, the existing PD schemes developed for terrestrial
environments may not be reactive enough for the NTN environment where
propagation delays are significantly longer. This paper proposes a dynamic PD
activation scheme for NTNs based on hybrid automatic repeat request feedback.
The scheme aims to reduce the number of duplicated packets while maintaining
high reliability. To evaluate the proposed scheme, simulations are conducted in
a scenario with two transparent payload lowearth orbit satellites. The results
show a significant reduction of 87.2% in the number of duplicated packets
compared to blind duplication, with only marginal compromise in reliability.Comment: Accepted for publication in 2023 IEEE International Conference on
Wireless for Space and Extreme Environments (WiSEE 2023
Deliverable D2.1 - Ecosystem analysis and 6G-SANDBOX facility design
This document provides a comprehensive overview of the core aspects of the 6G-SANDBOX project. It outlines the project's vision, objectives, and the Key Performance Indicators (KPIs) and Key Value Indicators (KVIs) targeted for achievement. The functional and non-functional requirements of the 6G-SANDBOX Facility are extensively presented, based on a proposed reference blueprint. A detailed description of the updated reference architecture of the facility is provided, considering the requirements outlined. The document explores the experimentation framework, including the lifecycle of experiments and the methodology for validating KPIs and KVIs. It presents the key technologies and use case enablers towards 6G that will be offered within the trial networks. Each of the platforms constituting the 6G-SANDBOX Facility is described, along with the necessary enhancements to align them with the project's vision in terms of hardware, software updates, and functional improvements
The Role of Physical Layer Security in Satellite-Based Networks
In the coming years, 6G will revolutionize the world with a large amount of
bandwidth, high data rates, and extensive coverage in remote and rural areas.
These goals can only be achieved by integrating terrestrial networks with
non-terrestrial networks. On the other hand, these advancements are raising
more concerns than other wireless links about malicious attacks on
satellite-terrestrial links due to their openness. Over the years, physical
layer security (PLS) has emerged as a good candidate to deal with security
threats by exploring the randomness of wireless channels. In this direction,
this paper reviews how PLS methods are implemented in satellite communications.
Firstly, we discuss the ongoing research on satellite-based networks by
highlighting the key points in the literature. Then, we revisit the research
activities on PLS in satellite-based networks by categorizing the different
system architectures. Finally, we highlight research directions and
opportunities to leverage the PLS in future satellite-based networks
A baseband wireless spectrum hypervisor for multiplexing concurrent OFDM signals
The next generation of wireless and mobile networks will have to handle a significant increase in traffic load compared to the current ones. This situation calls for novel ways to increase the spectral efficiency. Therefore, in this paper, we propose a wireless spectrum hypervisor architecture that abstracts a radio frequency (RF) front-end into a configurable number of virtual RF front ends. The proposed architecture has the ability to enable flexible spectrum access in existing wireless and mobile networks, which is a challenging task due to the limited spectrum programmability, i.e., the capability a system has to change the spectral properties of a given signal to fit an arbitrary frequency allocation. The proposed architecture is a non-intrusive and highly optimized wireless hypervisor that multiplexes the signals of several different and concurrent multi-carrier-based radio access technologies with numerologies that are multiple integers of one another, which are also referred in our work as radio access technologies with correlated numerology. For example, the proposed architecture can multiplex the signals of several Wi-Fi access points, several LTE base stations, several WiMAX base stations, etc. As it able to multiplex the signals of radio access technologies with correlated numerology, it can, for instance, multiplex the signals of LTE, 5G-NR and NB-IoT base stations. It abstracts a radio frequency front-end into a configurable number of virtual RF front ends, making it possible for such different technologies to share the same RF front-end and consequently reduce the costs and increasing the spectral efficiency by employing densification, once several networks share the same infrastructure or by dynamically accessing free chunks of spectrum. Therefore, the main goal of the proposed approach is to improve spectral efficiency by efficiently using vacant gaps in congested spectrum bandwidths or adopting network densification through infrastructure sharing. We demonstrate mathematically how our proposed approach works and present several simulation results proving its functionality and efficiency. Additionally, we designed and implemented an open-source and free proof of concept prototype of the proposed architecture, which can be used by researchers and developers to run experiments or extend the concept to other applications. We present several experimental results used to validate the proposed prototype. We demonstrate that the prototype can easily handle up to 12 concurrent physical layers
Satellite integration in 5G : contribution on network architectures and traffic engineering solutions for hybrid satellite-terrestrial mobile backhauling
The recent technological advances in the satellite domain such as the use of High Throughput Satellites (HTS) with throughput rates that are magnitudes higher than with previous ones, or the use of large non- Geostationary Earth Orbit (GEO) satellites constellations, etc, are reducing the price per bit and enhancing the Quality of Service (QoS) metrics such as latency, etc., changing the way that the capacity is being brought to the market and making it more attractive for other services such as satellite broadband communications. These new capabilities coupled with the advantages offered by satellite communications such as the unique wide-scale geographical coverage, inherent broadcast/multicast capabilities and highly reliable connectivity, anticipate new opportunities for the integration of the satellite component into the 5G ecosystem. One of the most compelling scenarios is mobile backhauling, where satellite capacity can be used to complement the terrestrial backhauling infrastructure, not only in hard to reach areas, but also for more efficient traffic delivery to Radio Access Network (RAN) nodes, increased resiliency and better support for fast, temporary cell deployments and moving cells.
In this context, this thesis work focuses on achieving better satellite-terrestrial backhaul network integration through the development of Traffic Engineering (TE) strategies to manage in a better way the dynamically steerable satellite provisioned capacity. To do this, this thesis work first takes the steps in the definition of an architectural framework that enables a better satellite-terrestrial mobile backhaul network integration, managing the satellite capacity as a constituent part of a Software Defined Networking (SDN) -based TE for mobile backhaul network. Under this basis, this thesis work first proposes and assesses a model for the analysis of capacity and traffic management strategies for hybrid satellite-terrestrial mobile backhauling networks that rely on SDN for fine-grained traffic steering. The performance analysis is carried out in terms of capacity gains that can be achieved when the satellite backhaul capacity is used for traffic overflow, taking into account the placement of the satellite capacity at different traffic aggregation levels and considering a spatial correlation of the traffic demand. Later, the thesis work presents the development of SDN-based TE strategies and algorithms that exploits the dynamically steerable satellite capacity provisioned for resilience purposes to better utilize the satellite capacity by maximizing the network utility under both failure and non-failure conditions in some terrestrial links, under the consideration of elastic, inelastic and unicast and multicast traffic. The performance analysis is carried out in terms of global network utility, fairness and connexion rejection rates compared to non SDN-based TE applications.
Finally, sustained in the defined architectural framework designs, the thesis work presents an experimental Proof of Concept (PoC) and validation of a satellite-terrestrial backhaul links integration solution that builts upon SDN technologies for the realization of End-to-End (E2E) TE applications in mobile backhauling networks with a satellite component, assessing the feasibility of the proposed SDN-based integration solution under a practical laboratory setting that combines the use of commercial, experimentation-oriented and emulation equipment and software.Los recientes avances tecnológicos en el dominio de los satélites, como el uso de satélites de alto rendimiento (HTS) con tasas de rendimiento que son magnitudes más altas que los anteriores, o el uso de grandes constelaciones de satélites de órbita no geoestacionaria (GEO), etc. están reduciendo el precio por bit y mejorando las métricas de Calidad de Servicio (QoS) como la latencia, etc., cambiando la forma en que la capacidad se está llevando al mercado, y haciéndola más atractiva para otros servicios como las comunicaciones de banda ancha por satélite. Estas nuevas capacidades, junto con las ventajas ofrecidas por las comunicaciones por satélite, como la cobertura geográfica a gran escala, las inherentes capacidades de difusión / multidifusión y la conectividad altamente confiable, anticipan nuevas oportunidades para la integración de la componente satelital al ecosistema 5G. Uno de los escenarios más atractivos es el backhauling móvil, donde la capacidad del satélite se puede usar para complementar la infraestructura de backhauling terrestre, no solo en áreas de difícil acceso, sino también para la entrega de tráfico de manera más eficiente a los nodos de la Red de Acceso (RAN), una mayor resiliencia y mejor soporte para implementaciones rápidas y temporales de células, así como células en movimiento. En este contexto, este trabajo de tesis se centra en lograr una mejor integración de la red híbrida de backhaul satélital-terrestre, a través del desarrollo de estrategias de ingeniería de tráfico (TE) para gestionar de una mejor manera la capacidad dinámicamente orientable del satélite. Para hacer esto, este trabajo de tesis primero toma los pasos en la definición de un marco de arquitectura que permite una mejor integración de una red híbrida satelital-terrestre de backhaul móvil, gestionando la capacidad del satélite como parte constitutiva de un TE basado en Software Defined Networking (SDN). Bajo esta base, este trabajo de tesis primero propone y evalúa un modelo para el análisis de la capacidad y las estrategias de gestión del tráfico para redes híbridas satelital-terrestre de backhaul móvil basadas en SDN para la dirección de tráfico. El análisis de rendimiento se lleva a cabo en términos de aumento de capacidad que se puede lograr cuando la capacidad de la red de backhaul por satélite se utiliza para el desborde de tráfico, teniendo en cuenta la ubicación de la capacidad del satélite en diferentes niveles de agregación de tráfico y considerando una correlación espacial de la demanda de tráfico. Posteriormente, el trabajo de tesis presenta el desarrollo de estrategias y algoritmos de TE basados en SDN que explotan la capacidad dinámicamente orientable del satelite, provista con fines de resiliencia para utilizar de mejor manera la capacidad satelital al maximizar la utilidad de red en condiciones de falla y no falla en algunos enlaces terrestres, y bajo la consideración de tráfico elástico, inelástico y de unidifusión y multidifusión. El análisis de rendimiento se lleva a cabo en términos de tasas de rechazo, de utilidad, y equidad en comparación con las aplicaciones de TE no basadas en SDN. Finalmente, basado en la definición del diseño de marco de arquitectura, el trabajo de tesis presenta una Prueba de concepto (PoC) experimental y la validación de una solución de integración de enlaces de backhaul satelital-terrestre que se basa en las tecnologías SDN para la realización de aplicaciones de TE de extremo a extremo (E2E) en redes de backhaul móviles, evaluando la viabilidad de la solución propuesta de integración basada en SDN en un entorno práctico de laboratorio que combina el uso de equipos y software comerciales, orientados a la experimentación y emulación.Postprint (published version
Open Platforms for Connected Vehicles
L'abstract è presente nell'allegato / the abstract is in the attachmen
- …