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Editorial for Wiley's IJSCN Special Issue “Satellite networks integration with 5G”
International Journal of Satellite Communications and Networking ( IF 1.7 ) Pub Date : 2021-06-02 , DOI: 10.1002/sat.1413
Konstantinos Liolis 1 , Antonio Franchi 2 , Barry Evans 3
Affiliation  

5G is the first truly multi-technology communication system which is expected to bring enhanced mobile broadband (eMBB), ultra-reliable and low-latency communication (URLLC), and massive machine-type communication (mMTC). Nowadays, the first terrestrial 5G systems are being rolled out worldwide. Attention is now focusing on additional attributes, such as global seamless connectivity, ubiquity, coverage, security, and resiliency, which can be effectively delivered by satellite. In fact, the satellite role in the 5G ecosystem is proven on the basis of its benefits and its integration into the overall network. The consensus and wider agreement on what satellite brings to achieve the 5G key performance indicators (KPIs) are as follows:
  • Ubiquity: Satellite can provide high-speed capacity across the globe addressing needs like capacity augmentation inside geographic gaps, overspill to satellite when terrestrial links are congested, general global wide coverage, backup/resilience for network fallback, and especially communication during emergency.
  • Mobility: Satellite is the only readily available technology capable of providing connectivity anywhere at sea or air for moving platforms, planes, ships, and trains.
  • Broadcast/multicast: Satellite can efficiently deliver rich multimedia and other content across multiple sites simultaneously using multicast streams with information centric network and content caching for local distribution.
  • Security/resilience: Satellite networks can provide efficient solutions for secure, highly reliable, rapid, and resilient deployment in challenging communication scenarios, such as in emergency responses and together with terrestrial networks where high availabilities are required.

As such, the 5G ecosystem opens up an opportunity to integrate terrestrial and satellite systems in order to achieve the goal of the attributes mentioned above (i.e., global seamless connectivity, ubiquity, coverage, security, and resiliency) across the family of 5G use cases—eMBB, URLLC, and mMTC. It is not only throughput and ubiquity that are crucial; latency and reliability are now becoming important metrics in future systems to provide acceptable quality of experience (QoE) across use cases.

To this end, the Third Generation Partnership Project (3GPP), as part of the 5G set of standardizations, has started working on Non-Terrestrial Networks (NTN) from Release 16 of the 5G standards, which includes satellites as well as high-altitude platform systems (HAPS) and unmanned aerial systems/vehicles (UASs/UAVs). In addition, various pre-commercial pilot deployments and over-the-air tests for satellite integration into 5G are being conducted worldwide. Moreover, several recent research, development, and innovation projects have been investigating the integration of satellites in 5G and have conducted several successful over-the-air demonstrations and validation campaigns paving the way for the seamless satellite integration into 5G. These recent activities—with the active involvement of the satellite and terrestrial mobile industry stakeholders—have resulted in inclusion of 5G features in satellite and non-terrestrial networks and their necessary integration and validation tests. Large-scale 5G testbeds have been developed to validate the end-to-end terrestrial-satellite 5G integrated system and their network performance and to demonstrate the seamless service delivery.

The ability to achieve full network convergence is predicated on software-defined network (SDN) design and network function virtualized (NFV) elements which can be orchestrated to form an end-to-end virtualized network, including both terrestrial and satellite elements. Moreover, new networking paradigms can now allow more efficient resource allocation schemes on an end-to-end basis with clear implications on the implementations and orchestration in both ground segment (e.g., radio access network [RAN], satellite hub stations, and core network) and space segment (e.g., onboard satellite payloads, HAPS, and UAS). In parallel, progress is being made to enhance the physical layer performance with novel interference mitigation/management and multiple access techniques coupled with the design of smarter antennas and multi-antenna signal processing.

The aim of this special issue has been to solicit and present advances in satellite and terrestrial networking technologies illustrating the many areas where 5G and satellites can be suitably and efficiently integrated in a unique system platform. As such, the papers presented in this special issue bring a sound balance between academic research and industrial development in order to provide a reference point for the know-how in this sector. In particular, this special issue includes nine original innovative papers which are overviewed hereinafter.

In Paper 1—“Techno-economic analysis of inflight connectivity using an integrated satellite-5G network”, the authors present a techno-economic analysis conducted within the EU H2020 5GPPP project “SaT5G” (Satellite and Terrestrial network for 5G) for in-flight connectivity using an integrated satellite–5G network. The demand for mobile broadband services is increasing exponentially alongside with user expectations regarding the reachability of these services and their prices. This paper presents an integrated satellite and 5G network for providing in-flight connectivity and evaluates the economic viability of offering broadband connectivity to passengers on commercial airplanes by the development of a techno-economic framework. Results show that satellite bandwidth usage leads to high operational costs. Therefore, caching popular content on the network onboard is beneficial to reduce the traffic carried over the satellite link. Furthermore, the framework is used to compare the identified business models for in-flight connectivity and their pricing strategies. Finally, a sensitivity analysis is elaborated in order to mitigate the uncertainty of inputs (e.g., rate of caching) used to feed the total cost of ownership (TCO) model. The following concrete recommendations are the main result of this research: (i) providing in-flight broadband services with a 2- to 5-Mbps throughput per user is feasible with a satellite and 5G integrated network; (ii) caching popular data reduces the operational costs and the average cost per user (from 25% to 32% depending on the caching rate adopted); and (iii) this framework allows to provide recommendations on the best suited business models and related pricing schemes.

In Paper 2—“An extensible network slicing framework for satellite integration into 5G”, the authors address an extensible network slicing framework for satellite integration into 5G. With the imminent deployment of 5G in the non-standalone version, some researches focus on network slicing to fully exploit the 5G infrastructure and achieve a high level of flexibility in the network. This level of flexibility offered by the network slicing paradigm also fits the need of satellite networks in which satellite network operators want to offer 5G connectivity services additionally to the traditional satellite connectivity. However, the work that has been done so far for network slicing in 5G does not directly apply to satellite networks due to satellite architecture specificities and thus needs to be extended. In this paper, the work on network slicing is extended and a novel satellite slicing framework is proposed in order to fully exploit the satellite infrastructure and to facilitate the integration of satellite services into 5G. Such framework includes definition, modeling, orchestration, and deployment of multiple satellite network slices and their associated network services on top of mutualized satellite infrastructures.

In Paper 3—“An integrated satellite–terrestrial 5G network and its use to demonstrate 5G use cases”, the authors address an integrated satellite–terrestrial 5G network and its use to demonstrate 5G use cases developed within the EU H2020 5GPPP project “SaT5G” (Satellite and Terrestrial network for 5G). The testbed's 3GPP Rel 15/6-compliant mobile core and RAN are first presented. It is then detailed how satellite NTN UE and gateway elements were integrated into the testbed using virtualization and software-defined orchestration. The satellite element provides 5G backhaul, which in concert with the terrestrial/mobile segment of the testbed forms a fully integrated end-to-end 5G network. The resulting hybrid 5G network is then used to validate the four major use cases defined within the SaT5G project: cellular backhaul, edge delivery of multimedia content, multicast and caching for media delivery, and multilinking using satellite and terrestrial. The multi-access edge computing (MEC) implementations developed to address each of the aforementioned use cases are described, and it is explored how each MEC system integrates into the 5G network. Measurements from trials of the use cases over a live GEO satellite system are also provided, and in each case, the improvements that result from the use of satellite in the 5G network are indicated.

In Paper 4—“Satellite integration into 5G: accent on testbed implementation and demonstration results for 5G Aero platform backhauling use case”, the authors address the testbed implementation and present demonstration results of tests conducted within the EU H2020 5GPPP project “SaT5G” (Satellite and Terrestrial network for 5G) for a 5G aeronautical platform backhauling use case. The SaT5G project addressed the plug-and-play integration of satellite communication into 5G. One of the SaT5G use cases corresponds to the delivery of 5G connectivity services to moving platforms such as aircraft via geostationary (GEO) and medium Earth orbit (MEO) satellite backhauling. With focus on this use case, this paper elaborates on the practical implementation and measurement results obtained within the 5G Aero testbed developed as part of the SaT5G project. The 5G Aero testbed activities focus on the next generation of connectivity and content distribution services to airplanes through satellite and terrestrial integration in 5G at the user, control, and management planes. SDN and NFV are key enablers to develop a powerful end-to-end testbed that can accelerate the adoption of MEC for the next-generation In-Flight Entertainment and Connectivity (IFEC) services, which use GEO and MEO satellite backhauling technologies. Hence, measurement results obtained from both over-the-air demonstration over the O3b MEO satellite constellation and in-lab validation over an emulated GEO satellite link are presented, towards the next-generation 5G-enabled IFEC services.

In Paper 5—“5G-VINNI use cases and testbed solutions for 5G cellular backhauling via satellite”, the authors address the use cases and testbed solutions developed within the EU H2020 5GPPP project “5G-VINNI” (5G Verticals Innovation Infrastructure) for 5G cellular backhauling via satellite. It presents the end-to-end design of the 5G-VINNI Norway and Luxembourg Facility Sites, which are currently under development and aim to showcase the satellite integration into 5G with focus on satellite backhauling solutions. It elaborates on the satellite transport network between the 5G RAN and the 5G Core Network (5GC), where design aspects on the satellite network integration into the standard 3GPP 5GC architecture are detailed. It also addresses the split of the 5GC between the central node and the edge node, where the edge node can be fixed and nomadic. The paper describes also the management and orchestration (MANO) and network functions virtualization infrastructure (NFVI) features of the 5G-VINNI Norway and Luxembourg Facility Sites.

In Paper 6—“Emergency 5G communications on-the-move: concept and field trial of a mobile satellite backhaul for public protection and disaster relief”, the authors address a concept and field trial of a 5G-enabled satellite communications on-the-move solution for the Public Protection and Disaster Relief (PPDR) vertical market. A secure and flexible communication infrastructure for the use of broadband and IP-based services is becoming more and more important in the context of PPDR. Government agencies and emergency responders need to be able to react quickly to emergencies across the globe. In particular, satellite-based 5G mobile networks can support government agencies during their critical tasks. In order to support the standardization committees and the industry, it is required to evaluate new architectures for such networks by utilizing testbeds and field trials. In this article, the authors propose and investigate architectures for mobile PPDR networks with satellite backhaul to ensure Communication on-the-Move (COTM). The flexibility within the architectures comes with the distribution of the core network nodes at the edge of the network applying the Core-Edge Split concept. The presented results show that existing interfaces of the Evolved Packet Core 3GPP standard allow satellite-based 5G networks to be tailored to the needs of government authorities.

In Paper 7—“5G satellite networks for IoT: backhauling and offloading”, the authors focus on the use of low-Earth orbit (LEO) satellite constellations for two specific purposes towards Internet of things (IoT): offloading and backhauling. The connection of IoT devices is one of the main drivers of 5G cellular networks. To achieve anytime, anywhere IoT connectivity, the next leap is to integrate NTN into 5G terrestrial systems to extend the coverage and complement the terrestrial service. Offloading allows offloading IoT traffic from a congested terrestrial network, usually in a very dense area. With respect backhauling, the constellation provides a multi-hop backhaul that connects a remote terrestrial gNB to the 5G core network. After providing an overview of the status of the 3GPP standardization process, the user data performance is modeled and analyzed in both cases, specifically in the uplink access and the satellite multi-hop constellation path. The evaluation of the collisions, the delay and the Age of Information, and the comparison of the terrestrial and the satellite access networks provide useful insights to understand the potential of LEO constellations for offloading and backhauling.

In Paper 8—“Integrating the 5G NR and satellite systems: main features, needed changes, and performance results”, the authors address the recent developments conducted within the EU H2020 5GPPP project “SaT5G” (Satellite and Terrestrial network for 5G) towards integrating the air interface of satellite communications into the upcoming 5G new radio (NR) systems. In particular, the focus is on harmonizing the physical (PHY) and medium access control (MAC) layers of both satellite and 5G NR systems by first identifying key features and incompatible procedures and then proposing suitable solutions to successfully integrate satellite and terrestrial networks. Moreover, proper use cases are defined and evaluated by means of computer simulations, as well as analytical models.

In Paper 9—“Licensed shared access (LSA) field trial and a testbed for 5G and beyond satellite-terrestrial communications”, the authors address a licensed shared access (LSA) field trial using live 5G networks in the spectrum sharing scenario between satellite and cellular networks. The trial focuses on 5G pioneer bands 3.4–3.8 and 24.25–27.5 GHz where the satellite system is operating in the downlink direction and a cellular system is accessing the same band. The performance evaluation in the trial concerns evacuation and frequency change times using different types of base stations, that is, how fast the system relinquishes the shared band to the primary user and continues transmission using other bands. It is shown that the proposed LSA system is scalable and able to support large number of base stations. In addition, it is investigated how satellite systems could reuse International Mobile Telecommunication (IMT) bands to offer enhanced satellite communication services for land, maritime, and aeronautical applications. Preliminary simulations and analysis confirm the possibility to reuse IMT spectrum for satellite systems without causing harmful interference, both with a satellite band allocation in the same and in the opposite direction from the terrestrial system.

The above papers have already produced results and recommendations which have been contributed to the 3GPP Rel 16 study work on NTN. Most of the existing work has concentrated on satellite backhaul applications and on eMBB use cases. 3GPP Rel 17 extends this work to mMTC (NB-IoT) and URLLC use cases. In addition, the direct satellite access to terminals via 5G NR air interface, which is addressed in one of the papers in this special issue, is receiving attention in 3GPP. This is perhaps particularly relevant to the non-GEO satellite constellations that are now starting to appear.

The emphasis thus far has been on research and demonstration of key techniques and technologies to demonstrate that an integrated satellite–terrestrial 5G solution is feasible. Progress will continue to be made via 3GPP Rel 17 onwards, towards standards for commercial availability in the next couple of years.



中文翻译:

Wiley 的 IJSCN 特刊“卫星网络与 5G 的集成”的社论

5G是第一个真正意义上的多技术通信系统,有望带来增强型移动宽带(eMBB)、超可靠低时延通信(URLLC)和海量机器类通信(mMTC)。如今,第一个地面5G系统正在全球范围内推出。现在的注意力集中在额外的属性上,例如全球无缝连接、无处不在、覆盖范围、安全性和弹性,这些属性可以通过卫星有效地提供。事实上,卫星在 5G 生态系统中的作用是基于其优势及其与整个网络的集成而得到证明的。关于卫星为实现 5G 关键性能指标 (KPI) 带来的共识和更广泛的共识如下:
  • 无处不在:卫星可以在全球范围内提供高速容量,以满足诸如地理间隙内容量增加、地面链路拥塞时卫星溢出、全球广泛覆盖、网络回退的备份/弹性,尤其是紧急情况下的通信等需求。
  • 移动性:卫星是唯一能够在海上或空中为移动平台、飞机、轮船和火车提供连接的现成技术。
  • 广播/多播:卫星可以使用多播流与信息中心网络和用于本地分发的内容缓存,有效地同时跨多个站点提供丰富的多媒体和其他内容。
  • 安全性/弹性:卫星网络可以为具有挑战性的通信场景中的安全、高度可靠、快速和弹性部署提供有效的解决方案,例如应急响应以及需要高可用性的地面网络。

因此,5G 生态系统为整合地面和卫星系统提供了机会,以便在 5G 用例系列中实现上述属性(即全球无缝连接、无处不在、覆盖、安全和弹性)的目标—eMBB、URLLC 和 mMTC。不仅吞吐量和无处不在是至关重要的;延迟和可靠性现在正在成为未来系统中的重要指标,以提供跨用例的可接受的体验质量 (QoE)。

为此,作为 5G 标准集的一部分,第三代合作伙伴计划 (3GPP) 已从 5G 标准第 16 版开始研究非地面网络 (NTN),其中包括卫星以及高空网络。平台系统(HAPS)和无人机系统/车辆(UAS/UAV)。此外,全球正在开展各种将卫星集成到 5G 的预商用试点部署和空中测试。此外,最近的几个研究、开发和创新项目一直在研究卫星与 5G 的集成,并进行了多次成功的空中演示和验证活动,为卫星与 5G 的无缝集成铺平了道路。这些最近的活动——在卫星和地面移动行业利益相关者的积极参与下——导致卫星和非地面网络中包含 5G 功能及其必要的集成和验证测试。已经开发了大规模的 5G 测试平台,以验证端到端的地面卫星 5G 集成系统及其网络性能,并展示无缝服务交付。

实现全网络融合的能力取决于软件定义网络 (SDN) 设计和网络功能虚拟化 (NFV) 元素,这些元素可以编排形成端到端的虚拟化网络,包括地面和卫星元素。此外,新的网络范式现在可以在端到端的基础上实现更有效的资源分配方案,对两个地面段(例如,无线电接入网络 [RAN]、卫星中心站和核心网络)的实施和编排具有明确的影响。 ) 和空间段(例如,星载卫星有效载荷、HAPS 和 UAS)。与此同时,正在通过新颖的干扰缓解/管理和多址技术以及更智能的天线和多天线信号处理的设计来增强物理层性能。

本期特刊的目的是征集和展示卫星和地面网络技术的进步,说明 5G 和卫星可以适当有效地集成到独特系统平台中的许多领域。因此,本期特刊中的论文在学术研究和产业发展之间取得了良好的平衡,以便为该领域的专业知识提供参考点。特别是,本期特刊收录了九篇原创创新论文,下文将对其进行综述。

在论文 1——“使用集成卫星 5G 网络对机上连接进行技术经济分析”中,作者介绍了在欧盟 H2020 5GPPP 项目“SaT5G”(5G 卫星和地面网络)内进行的技术经济分析,用于使用集成卫星-5G 网络的飞行连接。随着用户对这些服务的可达性及其价格的期望,对移动宽带服务的需求呈指数级增长。本文介绍了一种用于提供机上连接的集成卫星和 5G 网络,并评估了通过开发技术经济框架为商用飞机上的乘客提供宽带连接的经济可行性。结果表明,卫星带宽的使用会导致高运营成本。所以,在机载网络上缓存流行内容有利于减少通过卫星链路传输的流量。此外,该框架用于比较已确定的机上连接业务模型及其定价策略。最后,详细阐述了敏感性分析,以减轻用于提供总拥有成本 (TCO) 模型的输入(例如,缓存率)的不确定性。以下具体建议是这项研究的主要结果: (i) 使用卫星和 5G 集成网络提供每用户 2 至 5 Mbps 吞吐量的机上宽带服务是可行的;(ii) 缓存流行数据降低了运营成本和每个用户的平均成本(从 25% 到 32%,具体取决于采用的缓存率);

在论文 2——“用于卫星集成到 5G 的可扩展网络切片框架”中,作者讨论了用于卫星集成到 5G 的可扩展网络切片框架。随着 5G 非单机版的部署迫在眉睫,一些研究集中在网络切片上,以充分利用 5G 基础设施,实现网络的高度灵活性。网络切片范式提供的这种灵活性水平也符合卫星网络的需求,卫星网络运营商希望在传统卫星连接之外提供 5G 连接服务。然而,由于卫星架构的特殊性,迄今为止在 5G 中进行的网络切片工作并不直接适用于卫星网络,因此需要扩展。在本文中,扩展了网络切片的工作,并提出了一种新的卫星切片框架,以充分利用卫星基础设施并促进卫星服务与 5G 的集成。这种框架包括在相互化的卫星基础设施之上定义、建模、编排和部署多个卫星网络切片及其相关网络服务。

在论文 3——“一个集成的星地 5G 网络及其用于演示 5G 用例的用途”中,作者讨论了一个集成的星地 5G 网络及其用于演示在欧盟 H2020 5GPPP 项目“SaT5G”内开发的 5G 用例(用于 5G 的卫星和地面网络)。该测试平台的符合 3GPP Rel 15/6 标准的移动核心和 RAN 将首次亮相。然后详细介绍了如何使用虚拟化和软件定义的编排将卫星 NTN UE 和网关元素集成到测试平台中。卫星单元提供 5G 回程,与测试台的地面/移动部分共同构成一个完全集成的端到端 5G 网络。然后使用由此产生的混合 5G 网络来验证 SaT5G 项目中定义的四个主要用例:蜂窝回程、多媒体内容的边缘交付、媒体交付的多播和缓存,以及使用卫星和地面的多链路。描述了为解决上述每个用例而开发的多接入边缘计算 (MEC) 实现,并探讨了每个 MEC 系统如何集成到 5G 网络中。还提供了在实时 GEO 卫星系统上对用例进行试验的测量结果,并且在每种情况下,都指出了在 5G 网络中使用卫星所带来的改进。

在论文 4——“卫星集成到 5G:强调 5G Aero 平台回程用例的测试台实施和演示结果”中,作者讨论了测试台实施并展示了在欧盟 H2020 5GPPP 项目“SaT5G”(卫星和 5G 地面网络),用于 5G 航空平台回程用例。SaT5G 项目解决了卫星通信与 5G 的即插即用集成问题。SaT5G 用例之一对应于通过地球静止 (GEO) 和中地球轨道 (MEO) 卫星回程向移动平台(例如飞机)提供 5G 连接服务。本文重点关注此用例,详细介绍了在作为 SaT5G 项目的一部分开发的 5G Aero 测试台中获得的实际实施和测量结果。5G Aero 测试台活动的重点是通过用户、控制和管理平面 5G 中的卫星和地面集成,为飞机提供下一代连接和内容分发服务。SDN 和 NFV 是开发强大的端到端测试平台的关键推动因素,可以加速 MEC 在使用 GEO 和 MEO 卫星回程技术的下一代机上娱乐和连接 (IFEC) 服务中的采用。因此,针对支持下一代 5G 的 IFEC 服务,展示了从 O3b MEO 卫星星座的空中演示和模拟 GEO 卫星链路的实验室验证中获得的测量结果。

在论文 5——“通过卫星进行 5G 蜂窝回程的 5G-VINNI 用例和测试平台解决方案”中,作者讨论了在欧盟 H2020 5GPPP 项目“5G-VINNI”(5G 垂直创新基础设施)中为 5G 开发的用例和测试平台解决方案通过卫星进行蜂窝回程。它展示了目前正在开发的 5G-VINNI 挪威和卢森堡设施站点的端到端设计,旨在展示卫星与 5G 的集成,重点是卫星回程解决方案。它详细阐述了 5G RAN 和 5G 核心网 (5GC) 之间的卫星传输网络,其中详细介绍了卫星网络集成到标准 3GPP 5GC 架构的设计方面。它还解决了中心节点和边缘节点之间 5GC 的分裂,其中边缘节点可以是固定的和游牧的。

在论文 6——“移动中的紧急 5G 通信:用于公共保护和救灾的移动卫星回程的概念和现场试验”中,作者讨论了支持 5G 的卫星通信的概念和现场试验——公共保护和赈灾 (PPDR) 垂直市场的移动解决方案。在 PPDR 的背景下,用于使用宽带和基于 IP 的服务的安全和灵活的通信基础设施变得越来越重要。政府机构和应急响应人员需要能够对全球的紧急情况做出快速反应。特别是,基于卫星的 5G 移动网络可以在政府机构的关键任务中提供支持。为了支持标准化委员会和行业,需要利用测试平台和现场试验来评估此类网络的新架构。在本文中,作者提出并研究了具有卫星回程的移动 PPDR 网络架构,以确保移动通信 (COTM)。架构中的灵活性来自应用核心-边缘拆分概念的网络边缘的核心网络节点分布。所呈现的结果表明,演进分组核心 3GPP 标准的现有接口允许基于卫星的 5G 网络根据政府当局的需求进行定制。架构内的灵活性来自应用核心-边缘拆分概念的网络边缘的核心网络节点分布。所呈现的结果表明,演进分组核心 3GPP 标准的现有接口允许基于卫星的 5G 网络根据政府当局的需求进行定制。架构中的灵活性来自应用核心-边缘拆分概念的网络边缘的核心网络节点分布。所呈现的结果表明,演进分组核心 3GPP 标准的现有接口允许基于卫星的 5G 网络根据政府当局的需求进行定制。

在论文 7——“物联网的 5G 卫星网络:回程和卸载”中,作者专注于使用低地球轨道 (LEO) 卫星星座实现物联网 (IoT) 的两个特定目的:卸载和回程。物联网设备的连接是 5G 蜂窝网络的主要驱动力之一。为了实现随时随地的物联网连接,下一个飞跃是将 NTN 集成到 5G 地面系统中,以扩大覆盖范围并补充地面服务。卸载允许从拥挤的地面网络卸载物联网流量,通常位于非常密集的区域。在回程方面,该星座提供了一个多跳回程,将远程地面 gNB 连接到 5G 核心网络。在概述了 3GPP 标准化进程的状态之后,在两种情况下都对用户数据性能进行建模和分析,特别是在上行链路接入和卫星多跳星座路径中。碰撞评估、延迟和信息时代,以及地面和卫星接入网络的比较,为了解 LEO 星座卸载和回程的潜力提供了有用的见解。

在论文 8——“整合 5G NR 和卫星系统:主要特征、需要的变化和性能结果”中,作者讨论了欧盟 H2020 5GPPP 项目“SaT5G”(5G 卫星和地面网络)在整合方面的最新进展卫星通信的空中接口进入即将到来的 5G 新无线电 (NR) 系统。具体而言,重点是协调卫星和 5G NR 系统的物理 (PHY) 和媒体访问控制 (MAC) 层,首先确定关键特性和不兼容的程序,然后提出合适的解决方案以成功集成卫星和地面网络。此外,适当的用例是通过计算机模拟以及分析模型来定义和评估的。

在论文 9——“许可共享接入 (LSA) 现场试验和 5G 及卫星-地面通信以外的测试平台”中,作者讨论了在卫星和卫星之间的频谱共享场景中使用实时 5G 网络进行的许可共享接入 (LSA) 现场试验。蜂窝网络。该试验的重点是 5G 先锋频段 3.4-3.8 和 24.25-27.5 GHz,其中卫星系统在下行链路方向运行,蜂窝系统正在访问相同的频段。试验中的性能评估涉及使用不同类型基站的疏散和频率更改时间,即系统将共享频段放弃给主要用户并使用其他频段继续传输的速度。结果表明,所提出的 LSA 系统是可扩展的并且能够支持大量基站。此外,研究卫星系统如何重用国际移动电信 (IMT) 频段,为陆地、海上和航空应用提供增强的卫星通信服务。初步模拟和分析证实了在不造成有害干扰的情况下为卫星系统重新使用 IMT 频谱的可能性,无论是在与地面系统相同还是相反方向的卫星频段分配。

上述论文已经产生了结果和建议,这些结果和建议对 3GPP Rel 16 的 NTN 研究工作有所贡献。大多数现有工作都集中在卫星回程应用和 eMBB 用例上。3GPP Rel 17 将此工作扩展到 mMTC (NB-IoT) 和 URLLC 用例。此外,通过 5G NR 空中接口直接卫星接入终端,这在本期特刊的一篇论文中得到了解决,在 3GPP 中也受到了关注。这可能与现在开始出现的非 GEO 卫星星座特别相关。

迄今为止,重点一直放在关键技术和技术的研究和示范上,以证明集成的星地 5G 解决方案是可行的。将继续通过 3GPP Rel 17 向未来几年的商业可用性标准取得进展。

更新日期:2021-06-11
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