1,721,067 research outputs found
6G Non Terrestrial Networks (6G-NTN)
No full textThe 6G-NTN project aims at researching and developing innovative technical, business, regulatory, and standardization enablers to achieve full and seamless integration of the Non-Terrestrial Network (NTN) component into the 6G system and establish the European leadership in this domain. The vision is to extend coverage, resilience, and sustainability of next generation mobile networks, meeting needs and expectations of both vertical and consumer market segments, while unleashing new value chains and creating broad societal impact.
The proposed concept of full-fledged integration of the NTN component into 6G leverages multiple key project outcomes that will pave the way for a service roll-out in the 2030-35 time frame:
• a sustainable and resilient 3D multi-layered (GSO, NGSO, HAPS, drones) network architecture.
• a software defined payload adapted to all flying platforms and all frequency bands
• a very low Earth orbiting space segment
• a flexible waveform supporting terrestrial and non-terrestrial deployments.
• support of smart phones and vehicle/drone mounted terminals
• the use of new spectrum (i.e. C and Q/V bands) in coexistence with the terrestrial network component
• high accuracy and reliable positioning solutions.
The newly designed NTN component will deliver: i.e. uRLLC (latency < 10 ms) and advanced eMBB (data rate up to several hundred of Mbps) services to vehicle, drone mounted ultra-small size devices, and battery activated nomadic terminals; ii. improved eMBB services to smartphones; iii. short emergency messaging services to smartphones in light indoor/in-vehicle environments; and iv. high accuracy (<10 cm) and reliable location service to both devices categories.
By pulling together leading players across all involved industrial, research and innovation areas, the 6G-NTN ambition is to become the flagship R&I project to define the 6G NTN component and to drive its standardization in 3GPP
DYNAmic spectrum sharing and bandwidth-efficient techniques for high-throughput MIMO SATellite systems (DYNASAT)
No full textThe DYNASAT project aims at investigating, developing, and demonstrating bandwidth-efficient transmission techniques for an advance NGSO based satellite access infrastructure servicing mass-market and professional 5G user equipment (e.g. handset) in unserved or underserved areas.
The project will leverage the on-going effort on the definition at 3GPP (release 17) of the necessary features that will make 5G user devices and NG-RAN support satellite operations and on the development of an ambitious constellations to meet service requirements of mobile network operators requirements as well as of vertical stakeholders such as public safety and transportation sectors.
As the traffic demand keeps increasing, this project will timely develop selected bandwidth-efficient transmission techniques such as MIMO and dynamic spectrum access, frequency reuse, user clustering, CoMP and interference mitigation that will allow to scale the network infrastructure capacity and allow that it shares spectrum with cellular networks. Exploiting the research results, the consortium will contribute to 3GPP release 18 by promoting and then defining new features in the 5G standard.
The performance gain associated with the use of these techniques will be demonstrated at MWC 2022 and 2023. Moreover, the findings associated with the spectrum sharing techniques will be used to prepare the ITU WRC2023.
The project gathers partners with complementary expertise in the different bandwidth-efficient techniques, satellite communications and a proven successful record of impact in 3GPP where 5G is defined. It also involves in an advisory board prominent Mobile network and satellite operators as well as cellular stakeholders.
This project will enable Europe to maintain its leadership in future satellite solutions for 5G and address one of the key challenges of 5G which is to provide coverage in rural areas
The role of non-geostationary orbit satellite systems in 5G integration
No full textThe last years have seen an unprecedented demand for improved broadband connectivity, near-zero latency services, and ultra-reliable and heterogeneous communications. Such a trend is expected to further increase in the near future, with forecasts of 5.3 billion Internet users and 14.7 billion machine-to-machine (M2M) connections by 2023 [1]. The evolution of 5G into beyond 5G (B5G) and 6G networks aims at responding to this increasing need for ubiquitous and continuous connectivity services in all areas of our life: from education to finance, from politics to health, from entertainment to environment protection
Integration of Satellites in 5G through LEO Constellations
No full textThe standardization of 5G systems is entering in its critical phase, with 3GPP that will publish the PHY standard by June 2017. In order to meet the demanding 5G requirements both in terms of large throughput and global connectivity, Satellite Communications provide a valuable resource to extend and complement terrestrial networks. In this context, we consider a heterogeneous architecture in which a LEO mega-constellation satellite system provides backhaul connectivity to terrestrial 5G Relay Nodes, which create an on-ground 5G network. Since large delays and Doppler shifts related to satellite channels pose severe challenges to terrestrial-based systems, in this paper we assess their impact on the future 5G PHY and MAC layer procedures. In addition, solutions are proposed for Random Access, waveform numerology, and HARQ procedures
Reliability of adaptive transmission in state-based channels for Land Mobile Satellite communications
No full textThe modern approach in wireless multimedia communications is toward the adaptation of transmission parameters subject to internal and external requirements and constraints, represented by, e.g., the user QoS, the propagation environment, the traffic behavior, the external interferences. One of the most challenging issues that arises during the parameters adaptation is the temporal behavior due to the continuous change of the external context; in that sense it is important to focus the attention on the timing constraints that impact on the system capability of adapting the transmission parameters in a reliable way. The satellite communications (SatCom) are especially affected by the delay problems, due to the high propagation Round Trip Time (RTT). Herein we analyze the temporal behavior of the Land Mobile Satellite (LMS) environment, aiming to define a reliability index for different operational speeds and scenarios
An Energy Detector based Radio Environment Mapping Technique for Cognitive Satellite Systems
No full textThe increasing request of bandwidth for multimedia advanced services is one of the major issues of modern wireless systems. The spectrum shortage has been faced in several ways; among others the cognitive radio approach, aiming to exploit the unused spectrum resources already assigned to incumbent users, is maybe the most known. However, even if its application has been extensively proposed for wireless terrestrial communications, it remains a still unexplored area concerning Satellite Communications. The aim of this paper is to propose an Energy Detector based Radio Environment Mapping for the spectrum awareness functionality of a hybrid terrestrial/satellite scenario where the satellite components aim at exploiting the resources unused by terrestrial communications. The proposed approach allows to take advantage of cooperation between multiple sensing nodes evaluating spatial detection and false alarm probabilities besides their relationship with device detection and false alarm probabilities
Federated Beamforming with Subarrayed Planar Arrays for B5G/6G LEO Non-Terrestrial Networks
No full textNon-Terrestrial Networks (NTNs) will be an es-sential element in Beyond -5G (BSG) and 6G ecosystems, with the purpose of enabling seamless and global coverage, as well as supporting high data rate services. To achieve that, Full Frequency Reuse (FFR) schemes, along with digital beamforming techniques to cope with the Co-Channel Interference (CCI), are considered as promising strategies in 6G NTN. In this paper, we address the design of Cell-Free (CF) MIMO algorithms in NTN composed of multiple swarms of Non-GeoSynchronous Orbit (NGSO) nodes, in which each swarm performs distributed digital beamforming schemes. Furthermore, aiming at increasing the directivity of on-board antenna arrays for each NGSO node and enhancing the interference mitigation, we propose a Limited Field of View (LFoV) planar array architecture built up of smaller planar subarrays. We evaluate the performance of distributed beamforming schemes including both Channel State Information (CSI)-based, e.g., digital Minimum Mean Square Error (MMSE), and position-based such as analog Conventional Beamforming (CBF). We provide a numerical analysis of the performance in terms of per-user spectral efficiency. The results show that our proposed sub arrayed architecture designed for federated CF-MIMO beamforming outperforms the reference approach without subarraying in the proposed NTN system architecture
A Novel Twofold Approach to Enhance NB-IoT MAC Procedure in NTN
Get PDFThrough the transition from 5G to 6G, a significant rise in the number of Internet of Things (IoT) devices is anticipated, enabling pervasive and uninterrupted connectivity for several applications, in different verticals. Coping with the substantial influx of IoT devices and fulfilling the high capacity demands of different IoT technologies, such as NB-IoT, will necessitate the involvement of Non-Terrestrial Networks (NTNs), which will serve as crucial complements to terrestrial systems, enhancing the availability, resilience, and coverage of the network and will guarantee cost/benefit for some services and will fully satisfy some key requirements. Nevertheless, a primary obstacle to be faced when integrating IoT terrestrial communication systems in NTN, in particular with Non-Geostationary (NGSO) satellites, lies in the short visibility time of the flying platform due to its high speed. The latter introduces criticalities in various communication phases, including the Random Access (RA) procedure. In a highly congested scenario, the large Round Trip Delay and a limited visibility window, which varies for each user within the satellite’s coverage area, contribute to reducing the number of users successfully concluding the RA procedure. In this paper, to enhance the percentage of users who successfully conclude the RA, we introduce the concept of Coverage Enhancement Levels in time and a novel backoff mechanism, namely Smart Backoff, that leverages the beam coverage visibility period of individual users to adjust the random backoff interval. The numerical results obtained from our proposed scheme substantiate significant improvements compared to the standard backoff scheme. Specifically, our approach yields an increase of up to 16% per channel in the percentage of users who successfully complete the RA process
Evaluation of MU-MIMO Digital Beamforming Algorithms in B5G/6G LEO Satellite Systems
No full textSatellite Communication (SatCom) systems will be a key component of 5G and 6G networks to achieve the goal of providing unlimited and ubiquitous communications and deploying smart and sustainable networks. To meet the ever-increasing demand for higher throughput in 5G and beyond, aggressive frequency reuse schemes (i.e., full frequency reuse), combined with digital beamforming techniques to cope with the massive co-channel interference, are recognized as a key solution. Aimed at (i) eliminating the joint optimization problem among the beamforming vectors of all users, (ii) splitting it into distinct ones, and (iii) finding a closed-form solution, we propose a beamforming algorithm based on maximizing the users’ Signal- to-Leakage-and-Noise Ratio (SLNR) served by a Low Earth Orbit (LEO) satellite. We investigate and assess the performance of several beamforming algorithms, including both those based on Channel State Information (CSI) at the transmitter, i.e., Minimum Mean Square Error (MMSE) and Zero-Forcing (ZF), and those only requiring the users’ locations, i.e., Switchable Multi-Beam (MB). Through a detailed numerical analysis, we provide a thorough comparison of the performance in terms of per-user achievable spectral efficiency of the aforementioned beamforming schemes, and we show that the proposed SLNR beamforming technique is able to outperform both MMSE and ZF schemes in the presented SatCom scenario
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