《GSMA:2023年5G共建共享指南(英文版)(33页).pdf》由会员分享,可在线阅读,更多相关《GSMA:2023年5G共建共享指南(英文版)(33页).pdf(33页珍藏版)》请在三个皮匠报告上搜索。
1、1 27th February 2023 2 Overview This paper is a collaborative work between China Telecom,China Unicom,Datang Mobile,Ericsson,Huawei and ZTE based on experience in China of 5G Network Co-Construction and Sharing conducted in GSMA Foundry.Since 2019,China Telecom and China Unicom have been working on
2、5G network co-construction and sharing,with major breakthroughs made in technology development,networking,operations,and management.Together,they have built the worlds first,largest,and fastest 5G Standalone(SA)shared network,realising one physical network correlated with two logical networks,and mu
3、ltiple customised private networks.This whitepaper describes the technology development,operations,management,business models,and future evolution of 5G network co-construction and sharing the technologies and solutions which have been proven effective by the Chinese operators.Project Team Since the
4、 initiation of 5G network co-construction and sharing,the project team has been working on the development of related standards,technical researches,and business deployment.Our sincere gratitude goes to the team members from the following organizations for their contributions to this guide:China Tel
5、ecom China Unicom Datang Mobile Ericsson Huawei ZTE 3 Contents Preface.4 Current Status of Global 5G Development.5 Challenge.5 Significance of 5G Network Co-Construction and Sharing.6 Best Practice.7 Key Technologies of 5G Network Co-Construction and Sharing.9 Evolution of Standards for Mobile Commu
6、nication Network Co-Construction and Sharing.9 5G Network Sharing.11 RAN Sharing.11 National Inter-CN Roaming.18 Spectrum Sharing.19 Dynamic Spectrum Sharing(DSS).19 Power Sharing.21 Inter-Carrier Dynamic Power Sharing.21 Promoting Standards and Industrialisation.23 International Roaming in 5GSA Net
7、work Co-Construction and Sharing Scenarios 24 International Roaming Under National Inter-CN Roaming.24 Scenario Description.24 New requirements in 3GPP and GSMA.25 International Roaming Under RAN Sharing.26 Prospects for 5G Network Co-Construction and Sharing.27 Deepening Cooperation on 5G Network C
8、o-Construction and Sharing.27 Future Technology Evolution for Network Co-Construction and Sharing.28 Millimeter Wave.28 Edge Computing.29 6G Technologies.29 Glossary.31 4 Preface The advent of 5G is a major breakthrough in new-generation information and communication technologies which will enable d
9、igital transformation and accelerate future digital economic growth.Thanks to the potentially huge commercial value of 5G,acceleration of 5G network deployments has become the primary focus of global operators.However,the industry is faced with challenges in 5G network deployment.One challenge is ho
10、w to reduce network construction and operation costs,and how to benefit the billions of people in regions without advanced 5G communications infrastructure.To avoid repeated network construction by different individual operators,the 5G network co-construction and sharing solution described in this p
11、aper(hereafter termed“The CT/CU Deployment”)can reduce costs and energy consumption,effectively improve the spectrum utilisation,and enable broader deployment of advanced mobile networks.The CT/CU Deployment provides means to greatly reduce carbon emissions,and accelerates the development of both di
12、gital information infrastructure and the digital economy.The cooperation between operators will bring 5G services to more people in less time and at reduced cost.Since 2019,China Telecom and China Unicom have been working innovatively and cooperating on their solution,and have made major breakthroug
13、hs in 5G network sharing.So far,the operators have tackled many challenges in their network sharing journey,including doubling bandwidth,multi-frequency coexistence,network combination,and 4G/5G coordination,while ensuring good user experience over the network.In addition,they have built the worlds
14、first and largest 5G SA shared network,realising one physical network,two logical networks,and multiple customised private networks,and laying a solid foundation for large-scale industrial applications.This whitepaper describes the technologies,operation and management and business models used in th
15、e CT/CU Deployment as well as its future evolution.In this 5 whitepaper,as global leaders in 5G network sharing,China Telecom and China Unicom share their use of technologies,further insights and solutions regarding network sharing with the industry at large.The 5G Network Co-Construction and Sharin
16、g Guide is released by the GSMA as a whitepaper to the industry to facilitate future industry initiatives in network sharing.1.Current Status of Global 5G Development 1.1 Challenge Over the past few decades,the mobile communications industry has witnessed the evolution from 1G to 5G.A new mobile net
17、work generation emerges typically every ten years,bringing about breakthroughs in mobile technology and communications.Every intergenerational leap or technological progress has greatly promoted industrial upgrade as well as economic and social development,and therefore dramatically changed the way
18、we live and work.From analogue to digital communications,and from voice to data services,the network throughput has increased hundreds of times,and mobile communication networks have created a prosperous Internet economy.As a new-generation mobile communications network,5G networks not only provide
19、the ultimate user experience in Augmented Reality(AR),Virtual Reality(VR),and Ultra high Definition(UHD)videos,but also enable communication between people and things,and between things themselves,as well as meeting the application needs of vertical industries such as mobile medicine,internet of veh
20、icles,smart homes,industrial control,and environmental monitoring.To rapidly integrate 5G networks into all walks of life,5G infrastructure construction is the key to the digital,network-based,and intelligent transformation of the economy and society.So far,5.3 billion people around the world use mo
21、bile services,accounting for 67%of the worlds population.The proportion of 5G connections is expected to increase from 8%in 2021 to 25%by 2025.However,there is still no 5G network coverage in underdeveloped regions and countries.How to enable billions of people in such areas to enjoy mobile communic
22、ation services,experience the benefits brought by 5G and drive global economic and social development through 5G connectivity are still to be fully addressed by the global communications industry.6 1.2 Significance of 5G Network Co-Construction and Sharing 5G network co-construction and sharing is a
23、n effective solution to solve this challenge,not only by reducing repeated network investment,but also accelerating the construction of 5G networks and popularising 5G services and capabilities across developed and underdeveloped global geographies.Network co-construction and sharing provides four p
24、rimary benefits,including;the reduction of CAPEX,integration of operator resources for maximum efficiency,improvement in the quality of 5G services from the user perspective,and reductions of the carbon emissions of base stations.1.Reduction of CAPEX The higher network performance of 5G requires hig
25、her network infrastructure investment.Therefore,it is difficult for a single operator to achieve large-scale 5G network deployment in a short period of time.Thanks to the CT/CU Deployment,the two operators can coordinate their existing network resources,therefore providing better network performance
26、 through pace and scale of deployment,achieving a synergistic effect.2.Integration of operators resources for maximum efficiency The 5G spectrum at 3.5 GHz and 2.1 GHz of China Telecom and China Unicom are adjacent,so only one set of equipment is required to provide better network performance.Moreov
27、er,the network resources of the two operators are highly complementary in a number of ways,including spectrum and ownership of physical assets,in the southern and northern regions of China.Through the win-win cooperation on the construction and sharing of one 5G Radio Access Network(RAN)nationwide,t
28、he two operators achieved full 5G network coverage across the country,developed 5G service capabilities,enhanced the market competitiveness of 5G networks,and improved network and operational efficiency of assets.3.Improvement in the quality of 5G services from the user perspective With continuous d
29、evelopment of the digital economy,5G now carries expectations of both consumers and industries,but the process from nationwide coverage to the application and popularity of 5G networks is gradual.Network co-construction and sharing shortens the waiting time for 5G service provisioning,whilst seeing
30、a significant reduction in infrastructure construction expenditure.With the greater benefits of 5G services,the industry should make every effort to shift from 4G to 5G networks and promote the development of 5G networks,and to provide users with stable and high-quality 5G services.7 4.Reduction of
31、the carbon emissions of base stations Co-construction and sharing can dramatically decrease the number of nodes deployed in a network,improve the utilisation rate of nodes,and provide more services with increased social and economic benefits without increasing energy consumption,thereby effectively
32、reducing network power consumption and promoting green and innovative development.1.3 Best Practice:5G Network Co-Construction and Sharing between China Telecom and China Unicom China Telecom and China Unicom,signed the 5G Network Co-Construction and Sharing Framework Agreement in September 2019 for
33、 the construction of a nationwide 5G RAN by sharing 5G frequency resources while building 5G core networks independently.The two parties clearly defined their respective construction areas and the responsibilities in construction,investment,maintenance,and costs.In the subsequent implementation of 5
34、G co-construction and sharing,China Telecom and China Unicom continued to innovate in technical solutions,cooperation models,and management mechanisms.On September 30,2020,China Telecom and China Unicom completed the phase-1 construction and commercial deployment of the worlds first and largest 5G s
35、hared network,promoting 5G network construction and end-to-end SA network evolution.By December 2022,China Telecom and China Unicom had deployed about 1,000,000 base stations,accounting for more than 40%of all 5G base stations around the world,and built the worlds first and largest 5G SA shared netw
36、ork,realising large-scale industrial applications.In addition,the sharing of 4G RANs between the two operators was promoted,saving over USD 40 billion in network construction,and reducing network operations costs by USD 4 billion,electricity usage by more than 10 billion kWh,and carbon emissions by
37、10 million tons per year.China Telecom and China Unicom have proposed 12 contributions to international standards for 5G network co-construction and sharing,established the first national standard for RAN sharing technologies in China,and led development and implementation of global mobile communica
38、tion network sharing.China Telecom and China Unicom,together with their partners,have won various awards for the huge 8 achievements of this work,including;the iF Design Award in 2020 and 2021,the TM Forum Outstanding Catalyst Impact Society and Sustainability Award,the GTI Innovative Breakthrough i
39、n Mobile Technology Award,and the GSMA GLOMO and AMO awards.Over the past three decades,an ICT globalisation system based on the unification of standards,globalisation of technologies,products,supplies,and free flow of data has been taking shape.The 5G network co-construction and sharing advocated b
40、y China coincides with the vision of the Internet of Everything pursued by the telecommunications industry.The CT/CU Deployment will further promote the unification of industry standards,globalisation of supply chains,digitisation of society,free flow of data,and circulation of capital within the in
41、dustry.China Telecom and China Unicom are global pioneers in nationwide full-lifecycle 5G network co-construction and sharing.Through a series of innovative practices in products,technologies,operations&maintenance,and management,China Telecom and China Unicom have accelerated the implementation of
42、5G network co-construction and sharing,providing a Chinese Experience for the global telecommunications industry in the following aspects:Technology:practice of non-standalone(NSA)and SA network solutions,Dynamic Spectrum Sharing(DSS),power sharing,key technologies for co-construction and sharing ma
43、nagement,private network sharing,and international roaming solutions.Evolution:exploration in deepening 5G network co-construction and sharing in the future in terms of technical routes,geographic scope,number of partners,working frequency bands,and Radio Access Technologies(RATs).Facing the further
44、 challenges of millimeter wave spectrum sharing,indoor distribution sharing,edge computing sharing,and 6G sharing in the future,the two operators will continue to explore and innovate.9 2.Key Technologies of 5G Network Co-Construction and Sharing 2.1 Evolution of Standards for Mobile Communication N
45、etwork Co-Construction and Sharing Since 2000 when the 3G era started,some operators in Europe have been pressing for mobile communication network sharing,and the network sharing of operators around the world has been emerging continuously in various forms.Thanks to network sharing,repeated network
46、infrastructure construction is reduced and mobile communication services are quickly provided,benefiting users all over the world.From 2003 to 2004,3GPP issued 3G network sharing standards in Release 6.3GPP TS 23.251 defined the Multi-Operator Core Network(MOCN),including system information broadcas
47、ting,network selection and other basic functions,as well as the network sharing requirements for User Equipments(UEs),base stations,and Core Networks(CNs).3GPP TS 25.331 and other specifications have defined the related interface protocols and other requirements for network sharing.In Releases 8 and
48、 10,3GPP has respectively provided 4G and 2G network sharing specifications.Release 15 and later releases of 3GPP support RAN sharing and 5G MOCN,and standardised RAN sharing in terms of network architectures,air interfaces,NG interfaces,and Xn interfaces.TS 38.331 and other specifications have defi
49、ned more interface protocols and requirements for further network sharing.3GPPs requirements for network sharing continue to evolve in later releases.In Release 17,new operator-specific management of shared resources was added to adapt to multicell ID scenarios.In Release 18,further research was car
50、ried out on the co-construction and sharing management architecture,and the requirements for better O&M management were clarified.The Network Sharing Timeline in 3GPP is shown in Figure 2.1.10 Figure 2.1 Network Sharing Timeline in 3GPP Mobile communication network sharing refers to the sharing of i
51、nfrastructure or communication equipment among multiple operators.The infrastructure includes towers,buildings,and equipment rooms used for deploying base stations,whilst the communication equipment includes RAN,transport network,and CN equipment.In terms of operations management,there are two model
52、s of co-construction and sharing for operators.One is to independently build networks and share network resources based on business agreements,and the other is to set up a joint venture which operates independently and undertakes wireless network construction or maintenance.Network resource sharing
53、includes active sharing and passive sharing.Passive sharing refers to the sharing of infrastructure such as antenna poles(towers),and passive equipment in transport networks.Active sharing refers to the sharing of infrastructure in RANs such as base stations,including those used for RAN sharing and
54、national inter-CN roaming.In most cases,operators obtain their frequency band resources from a regulatory authority and invest them as shared resources in a shared network.As the proportion of shared resources increases,CAPEX gradually decreases,but deployment becomes more difficult to control and t
55、he coordination among operators becomes more complex.This whitepaper focuses on active sharing which,in comparison with the relatively mature passive sharing,requires better coordination among operators and more complex technical solutions.11 Figure 2.2 Network Resource Sharing Models Operators gene
56、rally take cost reduction as the first concern when choosing areas for network sharing.5G network co-construction and sharing is implemented in areas such as suburbs and rural areas,while in dense and general urban areas,independent networks are deployed to provide differentiated services and ensure
57、 differentiated network performance.2.2 5G Network Sharing 5G sharing includes RAN sharing and national inter-CN roaming.2.2.1 RAN Sharing 2.2.1.1 Technical Solutions 3GPP Standardised RAN sharing solutions support operators which intend to share radio resources(carriers).In case of MOCN,a single(lo
58、gical)RAN node controls the(shared)radio resources.In the case of RAN sharing with multiple cell ID broadcast radios,resources are commonly controlled by a set of logical RAN nodes(one RAN node per cell ID broadcast).Further,the industry adopted the term Multi-Operator RAN(MORAN)to denote a deployme
59、nt variant where the same RAN infrastructure(antennas,PAs,etc.)is used but each operator uses its own carrier.See Figure 2.3.12 Figure 2.3 Network Architecture for RAN Sharing(both Operator A and B share their RAN)In MORAN,multiple independent carriers are configured and the PLMN IDs of operators ar
60、e broadcasted on the carriers.Baseband Units(BBUs)are shared,and connected to Remote Radio Units(RRUs)and Active Antenna Units(AAUs)provided by the same vendor of BBUs.Each carrier is independently configured and managed.The RAN infrastructure provides logically and physically separated cell resourc
61、es and core network connectivity on a per operator basis.The MORAN solution features simple RAN infrastructure sharing and O&M,and is applicable to scenarios where operators need to maintain service and deployment independence in shared networks.In MOCN,one or more carriers are configured for freque
62、ncy sharing.Operators share their cells-physically and logically;in each cell,multiple Public Land Mobile Networks(PLMNs)are broadcasted.Sharing radio resources among participating operators is performed according to service level agreements.Parameterisation of cell-level features needs to be negoti
63、ated among all operators.UEs accessing shared cells select one of the broadcast PLMNs and communicate this selection to the gNodeB,which connect UEs to their(selected)core network,see Figure 2.4.The MOCN solution features high resource efficiency and is applicable to operators that closely cooperate
64、 with each other.For example,MOCN is used when operator A has a spectrum license,and operator does not have a spectrum license but would like to use the spectrum of operator A.13 RAN sharing with multiple cell ID broadcast is similar to MOCN in the sense that each operator deploys its own 5G Core(5G
65、C),but while MOCN requires the operators to coordinate their allocation schemes of cell identifiers and Tracking Area Codes,RAN sharing allows each operator to deploy respective allocation schemes independently.Figure 2.4 MORAN(left figure)and MOCN(right figure)MORAN MOCN Carriers Independent Shared
66、 Cell-level parameters Configured independently by operators Configured in a unified way by the hosting operator Mobility management Configured independently by operators Configured in a unified way or independently Impact on performance Independent Quality of Service(QoS)Flexible adjustment based o
67、n considerable network independence Independent QoS requiring operators to negotiate in advance More RAN resources available for sharing Service provisioning Implemented independently Implemented by multiple operators together Hardware Two carriers deployed,posing higher requirements for the bandwid
68、th and power supported by shared base stations Fast implementation based on existing hardware 14 Network adjustment Implemented independently Implemented in a unified way Table 2.1 Comparison Between MORAN and MOCN 2.2.1.2 Evolution from NSA Sharing to SA Sharing In terms of the network sharing in t
69、he NSA phase,core networks are independently established by operators,5G base stations are shared,and 4G anchor base stations are shared on demand,resulting in a complex network architecture.As shown in Figure 2.5,the X2 interface is required between the 4G base station and 5G base station for UE is
70、olation and interoperation.To implement the co-construction and sharing solution,the following two difficulties must be tackled:4G and 5G base stations must be provided by the same vendor.4G anchor base stations and 5G base stations must be deployed at the same site.Figure 2.5 Evolution from 4G Shar
71、ing to NSA Sharing There are two technical solutions for NSA sharing:dual-anchor solution and single-anchor solution.See Figure 2.6.15 Figure 2.6 Dual-Anchor(left figure)and Single-Anchor(right figure)Solutions Dual-Anchor Solution Single-Anchor Solution Sharing 4G base stations are not shared,and 5
72、G base stations are connected to respective 4G anchor base stations.TX2 interfaces are required between 4G and 5G base stations,which must be provided by the same vendor.5G base stations are connected to the same shared 4G anchor base station,and all the base stations must be provided by the same ve
73、ndor and located at the same site.Features Fast network deployment leads to good user experience.The requirements for the areas where networks are to be deployed are strict.There are less requirements for the areas where networks are to be deployed.Table 2.2 Comparison Between Dual-Anchor and Single
74、-Anchor Solutions The dual-anchor solution is applicable to scenarios where the 4G base stations of all operators as well as the 5G base stations of the hosting operator are provided by the same vendor.Otherwise,X2 interface incompatibility problems may occur.The dual-anchor solution can quickly ach
75、ieve 5G network co-construction and sharing with minor changes to existing 4G networks.16 The single-anchor solution is applicable to scenarios where 4G base stations of operators are provided by different vendors.However,this solution requires a complex reconstruction of existing 4G networks or the
76、 establishment of a new 4G anchor.With this solution,5G networks can be shared while 4G non-anchor base stations are not.In the NSA phase,voice services are carried over only LTE networks,i.e.Voice over LTE(VoLTE).The complex technical solutions for NSA sharing involve a large amount of work in reco
77、nstruction and cause difficulties in network management and optimisation.Therefore,an evolution to SA sharing,should be performed as soon as possible to improve network quality.Figure 2.7 Evolution from NSA to SA sharing After the evolution to 5G SA sharing,operators only need to connect 5G base sta
78、tions to respective 5GCs,without the reconstruction of 5GCs.In addition,transport networks should be scaled out as required,the base station sharing function should be enabled for 5G base stations,and 4G base stations should be configured as neighbour cells.With the 5G network decoupled from 4G netw
79、orks,no complex anchor coordination solution is needed,easy optimisation of the 5G 17 network is made possible,and good user experience is guaranteed in both 4G and 5G networks.In the SA phase,there are two voice service solutions:Voice over New Radio (VoNR)and Evolved Packet System(EPS)fallback.EPS
80、 fallback allows UEs to fall back either to their operators LTE networks if 5G base stations are shared,or to the hosting operators LTE network if both 5G and 4G base stations are shared(if 4G base stations have been shared in the NSA phase,they do not need to be reconstructed),see Figure 2.8.Figure
81、 2.8 Fallback of UEs to their Operators LTE Networks After fallback,voice services are provided via LTE networks to ensure voice service continuity,while only data services are in NR networks.If a UE initiates a voice call,a handover is triggered when the gNodeB establishes an IP Multimedia Subsyste
82、m(IMS)voice channel in the NR network.In this case,the gNodeB sends a redirection or inter-RAT handover request to the 5GC.After the UE falls back to the LTE network,its voice services are implemented based on VoLTE.EPS fallback allows 5G UEs to camp on NR networks where voice services are not provi
83、ded.Since there is latency in the fallback procedure,the call setup duration increases.The VoNR solution requires only 5G base stations to be shared.NR networks are connected to the 5GC while LTE networks are connected to the Evolved Packet Core(EPC).In NR networks,VoNR is used to provide voice serv
84、ices,and 18 at the 5G network edge,UEs are handed over to their LTE networks through the N26 interface and the voice services are continued on LTE.VoNR improves voice quality and allows all the data and voice services of a UE to be implemented in the same NR network.2.2.2 National Inter-CN Roaming 2
85、.2.2.1 Technical Solutions The core networks involved in national inter-CN roaming are established by respective operators.The core network of the hosting operator is interconnected with that of the participating operator.Base stations are shared between operators and connected to only the hosting o
86、perators core network,see Figure 2.9.Unlike international roaming,a national inter-CN roaming UE in the visited area may receive signals from the Home PLMN(HPLMN),because the area is covered by the 4G/5G signals of the hosting operators network and the 4G signals of the participating operators netwo
87、rk at the same time,resulting in a network selection problem for the UE.Figure 2.9 Network Architecture for National Inter-CN Roaming with shared base stations 2.2.2.2 4G/5G Core Network Interconnection and Evolution In the NSA phase,the EPC networks of operators are interconnected,and NSA networks
88、are constructed in different areas.5G NSA UEs and 4G UEs can use the same roaming policy or different roaming policies,depending on network coverage,planning,and business cooperation.If operators have used national inter-CN roaming in the 4G phase,the same roaming policy is used for 4G and 19 NSA UE
89、s in the NSA sharing phase.If operators have not used national inter-CN roaming in the 4G phase and need to directly implement NSA sharing,different roaming policies need to be used for 4G and NSA UEs to ensure that NSA UEs roam to the coverage area of the shared NSA network and 4G UEs attached to 4
90、G networks.To implement such roaming policies,on base stations,Mobility Management Entities(MMEs)and other Network Elements(NEs),operators need to configure a mobility management policy and related information based on the RAT Frequency Selection Priority(RFSP),mobility restriction and other technol
91、ogies to control inter-PLMN mobility.In the SA sharing phase,a roaming UE can access a 5G Visited PLMN(VPLMN)to use 5G services.In national inter-CN roaming mode,the RANs and 5GCs of operators are independently constructed and managed,and UEs are separately managed.National inter-CN roaming is imple
92、mented through home routing.That is,the data of a roaming UE is returned to the HPLMN,and the HPLMN provides services for the UE.The networks involved in national inter-CN roaming should provide IMS-based voice and video services(including emergency call services),Short Message Service(SMS)over IP(i
93、.e.via IMS),and data services for UEs,and the involved operators should provide services for roaming UEs based on an inter-network roaming protocol.2.3 Spectrum Sharing Refarming 4G spectrum for rapid 5G network deployment has become a global consensus,and about 50%of global 5G operators have put su
94、ch refarming into application.As 4G services and UEs will still exist,a major challenge is how to coordinate the 4G and 5G development strategies and pace of the participating and hosting operators in the 5G co-construction and sharing network,so as to guarantee good user experience.Against such a b
95、ackdrop,China Telecom and China Unicom adopt the DSS technology.The DSS technology saves network investment by taking account of the different 4G and 5G development strategies and deployment timescales of operators.2.3.1 Dynamic Spectrum Sharing(DSS)Challenges 20 In the early stage of 5G,4G traffic
96、is much heavier than 5G traffic,so there exists an opportunity to optimise the use of spectrum when deploying standalone 5G networks.Innovation China Telecom and China Unicom have proposed the DSS technology to promote the coordinated development of 4G and 5G based on the LTE 2.1 GHz frequency band
97、that features strong penetrability see Figure 2.10.With the DSS technology,5G networks can be rapidly deployed without affecting 4G user experience,effectively improving spectrum efficiency and meeting different service requirements of both 4G and 5G users.Figure 2.10 DSS Technology In this solution
98、,both 4G and 5G service requirements should be collected and prioritised,and spectrum resources be allocated based on the priorities,so that the 4G and 5G spectrum resources can be dynamically shared.Figure 2.11 shows how the DSS solution works.For dynamic spectrum sharing,LTE and NR services use th
99、e same spectrum,and the interference between them can be prevented or reduced by using such technologies as Cell-Specific Reference Signal(CRS)rate adaptation,Multimedia Broadcast Multicast Service Single Frequency Network(MBSFN)subframe,and Zero Power Channel State Information Reference Signal(ZP C
100、SI-RS).The potential increase in the overhead of 4G and 5G Physical Downlink Control Channels(PDCCHs)after the DSS solution is used can be minimised through efficient PDCCH allocation.21 Figure 2.11 DSS Solution The spectrum resources allocated for NR and LTE can be dynamically adjusted in accordanc
101、e with the number of connected 4G and 5G UEs,thus ensuring the optimal uplink and downlink performance.In addition,4G and 5G Physical Downlink Shared Channels(PDSCHs)and Physical Uplink Shared Channels(PUSCHs)can be shared in real time and scheduled at millisecond level based on service requirements
102、 to improve spectrum efficiency.Technical Achievements By taking 4G and 5G service requirements into account and coordinating the development strategies and service requirements of operators involved in network sharing,the DSS technology provides an intelligent adaptation policy for the long-term ne
103、twork evolution.The DSS solution won the Best Mobile Technology Breakthrough award in 2018.2.4 Power Sharing 2.4.1 Inter-Carrier Dynamic Power Sharing Challenges Currently,the maximum transmit power of an AAU with Massive Multiple Input Multiple Output(MIMO)on the 3.5 GHz frequency band is 320 W,and
104、 the transmit power of each 100 MHz cell is 200 W.In the CT/CU Deployment,the minimum bandwidth shall be 200 MHz on the 3.5 GHz frequency band.If a second carrier is enabled,the average power of each carrier is only 160 W,resulting in 1 dB lower 22 power in coverage.Therefore,how to enable the secon
105、d carrier without deteriorating the coverage performance becomes an urgent issue.Innovation To address this issue,power resource pooling and dynamic power sharing are introduced.As shown in Figure 2.12,the power resource pooling technology allows dynamic power sharing between two carriers and flexib
106、le power allocation in a unified manner.The dynamic power sharing technology actively allocates power to two carriers based on service requirements.This ensures lossless coverage performance when the second carrier is enabled in lightly-loaded networks.Figure 2.12 Dynamic Power Sharing Technical Ach
107、ievements The application on the live network in Anhui province shows that the average user experience in downlink services improves by 5%to 20%after the dynamic power sharing technology is used.23 2.5 China Telecom and China Unicom Promoting Standards and Industrialisation of 5G Network Co-Construc
108、tion and Sharing 2.5.1 Taking the lead in the project initiation of seven 5G international standards and seven industry standards,significantly enhancing the influence of 5G network co-construction and sharing on industry chains China Telecom and China Unicom took the lead in the initiation of four
109、3GPP specification projects:2.1 GHz 40/50 MHz bandwidth Frequency Division Duplexing(FDD)NR,NSA 26 dBm high-power UE,FDD Massive MIMO,and 5G Quality of Experience(QoE).The 2.1 GHz 40/50 MHz bandwidth FDD NR greatly promotes the technical evolution of FDD NR high bandwidth,and provides strong impetus
110、 for FDD spectrum refarming and improvement in network competitiveness.China Telecom and China Unicom launched the worlds first base station(with a RRU)that supports both the 1.8 GHz and 2.1 GHz frequency bands and can operate at full power,and implemented the first 2.1 GHz 40/50 MHz bandwidth test
111、in April 2020,promoting the development of high-bandwidth FDD NR UEs.China Telecom and China Unicom led the project initiation of the following industry standards in the CCSA:Research on Smart Energy Saving of 5G Base Stations,Technical Requirements for 5G Network Co-Construction and Sharing,Test Me
112、thods for 5G Network Co-Construction and Sharing,Technical Requirements for 5G Digital Indoor Distribution,and Test Methods for 5G Digital Indoor Distribution.2.5.2 Taking the lead in the outdoor 200 MHz bandwidth technology and achieving the peak downlink data rate 2.7 Gbps 24 To take advantage of
113、spectrum sharing,improve the competitiveness of 5G networks,and fully implement high-bandwidth capabilities,the operators enable base stations to support 200 MHz bandwidth in conjunction with Carrier Aggregation(CA).This enables 5G networks to meet the application requirements whilst making full use
114、 of the high bandwidth and large capacity of the 3.5 GHz frequency band and achieving a peak downlink data rate of 2.7 Gbps to a single user.See figure 2.13.Figure 2.13 Outdoor 200 MHz Bandwidth Technology 3.International Roaming in 5G SA Network Co-Construction and Sharing Scenarios 3.1 Internation
115、al Roaming Under National Inter-CN Roaming 3.1.1 Scenario Description In the 5G SA scenario,an operator can deploy a shareable network.For example,operator 1(OP1)shares its RAN with operator 2(OP2),and operator 3(OP3)is a roaming partner of OP2.In this case,the UEs of OP3 can connect to the shared R
116、AN of OP1 to access the services of OP2.Figure 3.1 illustrates the network architecture for national inter-CN roaming in the 5G SA scenario.25 Shared NG-RANof OP1NG-RANof OP25G core network of OP25G core networkof OP15G core networkof OP3DNUE of OP3 Figure 3.1 Scenario of International Roaming Users
117、 in national Inter-CN Roaming As shown in the figure,three operators(OP1,OP2,and OP3)are involved in this scenario.OP1 not only shares its RAN with OP2,but also makes its core network shareable for inbound roamers of OP2.OP2 signs a 5G network sharing agreement with OP1 for sharing the RAN of OP1.OP
118、3 is a roaming partner of only OP2(that is,they have signed a roaming agreement).Since OP2 has signed a 5G network sharing agreement with OP1,the UEs of OP2 can connect to the shared RAN of OP1 to access the services of OP2.In addition,OP3s UEs roaming in OP2s dedicated RAN or OP1s shared RAN can ac
119、cess the services of OP2 through the corresponding RAN.3.1.2 New requirements in 3GPP and GSMA In Release 18,3GPP TS 23.501 only supports 5G MOCN,and 3GPP specifications describe roaming covering both national and international roaming in the 5G SA scenario.3GPP SA1 initiated in Release 19 the Feasi
120、bility Study on Network Sharing Aspect,documented in TR 22.851,attaching greater importance to the feasibility of more sharing modes.Section 5 of TR 22.851 covers Use case on International Roaming Users in a Shared Network and includes as potential new requirements to support the use case.PR 5.4.6-0
121、01 The 5G system shall enable the shared access network of a hosting operator with indirect connection between the shared access network and a participating operators core network to provide services for inbound roaming users.26 In addition,GSMA PRD NG.113(5GS Roaming Guidelines)only supports bilate
122、ral roaming.Unlike the serving networks in bilateral roaming,a serving network in national inter-CN roaming involves multiple operators.Therefore,how to increase support for international roaming under national inter-CN roaming in the 5G SA scenario requires further work in the GSMA.3.2 Internationa
123、l Roaming Under RAN Sharing In RAN sharing,multiple operators share one 5G RAN,but their 5GCs are independent.As shown in Figure 3.2,the shared 5G RAN is connected to the 5GCs built by respective operators via Next Generation(NG)interfaces.Figure 3.2 Roaming Under RAN Sharing in the 5G SA Scenario R
124、oaming under RAN sharing in the 5G SA scenario includes Home-Routed(HR)roaming and Local Breakout(LBO)roaming.The international roaming procedure in the 5G SA scenario after a UE accesses the corresponding PLMN is the same as the standard international roaming procedure.3GPP has defined the interfac
125、es related to international roaming in the 5G SA scenario.For details,refer to GSMA PRD NG.113,3GPP TS 23.501,and 3GPP TS 23.502.27 4.Prospects for 5G Network Co-Construction and Sharing 4.1 Deepening Cooperation on 5G Network Co-Construction and Sharing Figure 4.1 illustrates the evolution of 5G ne
126、twork co-construction and sharing from the perspective of technical routes,geographic scope,number of partners,operating frequency band,and RAT.Figure 4.1 Evolution of 5G Network Co-Construction and Sharing 1)Technical routes:Focusing on RAN sharing,operators should also determine other technologies
127、 such as national inter-CN roaming for 5G network co-construction and sharing.2)Geographic scope:Operators should consider the geographic scope for 5G network co-construction and sharing,including indoor scenarios.3)Number of partners:Operators can also extend 5G network co-construction and sharing
128、to more than two partners.4)Operating frequency band:5G systems can operate on multiple frequency bands,such as 3.5 GHz,2.6 GHz z,2.1 GHz,700 MHz,and 800 MHz.With the deepening of 5G network co-construction and sharing,more frequency bands such as millimeter wave will be used.2 3 4 partner size geog
129、raphical scope technical standards 5G 5G+4G More standards National Townships,rural areas Remote areas technical routes operating bands 28 5)RAT:As 5G network co-construction and sharing advances,4G RATs,including 4G Narrowband Internet of Things(NB-IoT)and Enhanced Machine Type Communication(eMTC),
130、may also be involved.The above aspects should be comprehensively taken into account for further development of 5G network co-construction and sharing.For example,to provide more options for such scenarios as indoor infrastructure sharing,vendors should continue to develop new devices in terms of dev
131、ice forms and deployment modes.In addition,they need to choose the most optimum operating frequency band to meet different geographic requirements.For instance,in remote areas,sub-1GHz bands should be used for 5G network co-construction and sharing.4.2 Future Technology Evolution for Network Co-Cons
132、truction and Sharing 4.2.1 Millimeter Wave Featuring high bandwidth and low latency,millimeter Wave(mmWave)is crucial for both current and future 5G network development.The mmWave frequency bands will coexist with other frequency bands in the long term,as 5G networks need both high and low frequency
133、 bands.ER-UTRA NR Dual Connectivity(EN-DC),NR Dual Connectivity(NR-DC)and Frequency Range 1(FR1)+Frequency Range 2(FR2)Carrier Aggregation(CA)enable optimal utilisation of high and low frequency bands in different stages of 5G development,making mmWave play a full part in 5G network co-construction
134、and sharing scenarios.With the global popularity of 5G,mmWave frequency bands can be used as a supplement to the main frequency bands(medium and low frequency bands)of 5G networks.When using high-traffic services,a terminal can use mmWave to offload traffic.NR-DC/CA can be adopted to implement bette
135、r inter-frequency coordination for the devices from the same vendor,and only the frequencies in FR2 are used for the devices of different vendors in 5G network co-construction and sharing.The priority-based carrier scheduling and load balancing help to maximise the utilisation of medium and low freq
136、uency bands.29 4.2.2 Edge Computing To achieve ultra-large-scale computing and short latency,cloud servers and edge servers should be deployed close to users to run applications with stringent requirements on computing and latency in 5G networks,thus ensuring the good operation of industrial applica
137、tions through cloud-pipe-terminal coordination.The Edge Computing(EC)technology introduced in 5G networks supports a variety of industrial applications that impose high requirements on network latency and data security.In a shared network,the hosting operator and participating operators can share th
138、e computing power of the edge servers,which coordinate with the cloud servers and terminals to flexibly schedule and transfer computing resources.In this way,the QoS of edge computing applications as well as the coverage of edge computing is improved,thus attracting more third-party applications and
139、 ultimately providing better user experience.4.2.3 6G Technologies With the acceleration of 5G network construction,a variety of applications are flourishing in vertical industries.As a new generation of mobile communication systems emerge about every ten years,it is predicted that 6G will be commer
140、cially available around 2030.At present,many countries have issued whitepapers on 6G visions.The expectations for next-generation networks,especially those for key technologies,are all incorporated into the 6G visions.The 6G visions include instantaneous speed,ubiquitous 3D connectivity,integrated s
141、ensing&communication,intrinsic intelligence,smart simplicity,security&trust,sustainability&sharing,and flexibility&openness.To realise these visions,various network virtualisation technologies have been proposed,such as mmWave and terahertz,satellite-integrated space-air-ground-sea connectivity,high
142、-frequency multi-sensory data fusion,intelligent semantic communication,cloud-network convergence and computing power networks,instinct security,and intelligent energy saving.6G network co-construction and sharing is still in the research stage.With the development of key 6G technologies,the followi
143、ng three aspects are expected to become the focus in the next few years:30 Smart simplicity:In the face of massive service access and dynamic network requirements in the future,network design should be oriented towards simplicity and decentralisation,unifying basic interface protocols and access man
144、agement modes.In co-construction and sharing,multiple operators can share network resources,thus providing seamless network access.Network compatibility:The 6G network should be compatible with traditional networks.In co-construction and sharing,smooth voice and data services can be guaranteed durin
145、g inter-PLMN or inter-RAT handover.So far,many countries have started to promote research on 6G technologies,which will definitely drive the mobile communication industry to new heights.Unified international communication standards are essential for the success of 6G.Therefore,China Telecom and Chin
146、a Unicom will unswervingly participate in the formulation and update of the standards,promoting 6G globalisation and the development of the community with a shared future for mankind.31 Glossary 1G 1st Generation(of Mobile Technology)2G 2nd Generation(of Mobile Technology)3G 3rd Generation(of Mobile
147、 Technology)4G 4th Generation(of Mobile Technology)5G 5th Generation(of Mobile Technology)5GC 5G Core(Network)6G 6th Generation(of Mobile Technology)AAU Active Antenna Unit AI Artificial Intelligence AR Augmented Reality BBU-Baseband Unit CA Carrier Aggregation CAPEX Capital Expenditure CCSA China C
148、ommunications Standards Association CN Core Network CRS-Cell-Specific Reference Signal DSS Dynamic Spectrum Sharing ECGI E-UTRAN CGI FR1 Frequency Range 1 FR2 Frequency Range 2 EC Edge Computing eMTC Enhanced Machine Type Communication EN-DC E-UTRA-NR Dual Connecttivity EPC Evolved Packet Core EPS E
149、volved Packet System E-UTRA Evolved UMTS Radio Access FDD-Frequency Division Duplexing HPLMN Home PLMN ICT Information&Communications Technology ID Identity IP Internet Protocol IMS IP Multimedia Subsystem KPI Key Performance Indicators LBO Local Break-Out LTE Long Term Evolution MBSFN-Multimedia Br
150、oadcast multicast service Single Frequency Network MES Manufacturing Execution System MIMO Multiple Input Multiple Output MME Mobility Management Entity MOCN Multi-Operator Core Network MORAN Multi-Operator Radio Access Network MU-MIMO Multi-User MIMO NB-IoT Narrow Band Internet of Things NG Next Ge
151、neration NR New Radio NR-DC NR Dual Connectivity NSA Non-Standalone O&M Operations&Maintenance 32 PDCCH-Physical Downlink Control Channel PDSCH Physical Downlink Shared Channel PUSCH Physical Uplink Shared Channel PLMN Public Land Mobile Network QoE Quality of Experience QoS Quality of Service RAN R
152、adio Access Network RAT Radio Access Technology RFSP RAT Frequency Selection Priority RRU Remote Radio Unit SA Standalone SMS Short Message Service TDD Time Division Duplexing TNR TDD NR TTI Transmission Time Interval UE User Equipment UHD Ultra Hi-Definition UMTS Universal Mobile Telecommunications
153、 System UPF User Plane Function USD United States Dollar VPLMN Visited PLMN VoLTE Voice over LTE VR Virtual Reality ZP CSI-RS-Zero Power Channel State Information Reference Signal 33 About this whitepaper This is a GSMA whitepaper and is a public document subject to copyright protection.The GSM Asso
154、ciation makes no representation,warranty or undertaking(express or implied)with respect to and does not accept any responsibility for,and hereby disclaims liability for the accuracy or completeness or timeliness of the information contained in this document.The information contained in this document
155、 may be subject to change without prior notice.The information contained herein is in full compliance with the GSM Associations antitrust compliance policy.Copyright 2023 GSM Association About GSMA The GSMA is a global mobile industry association that represents the interests of mobile operators wor
156、ldwide,uniting more than 750 operators with almost 300 companies in the broader mobile ecosystem,including handset and device makers,and software companies.The GSMA also holds the industry-leading events such as Mobile World Congress(in Barcelona,Shanghai and Los Angeles)and the Mobile 360 Series.GS
157、MA Foundry is the go-to place for cross-industry collaboration and business development,where GSMA members and industry players come together to rapidly develop real-world solutions to industry challenges,nurture new ideas through initial commercial trials and scale proven solutions at a regional and global level to forge our digital future.For more information,please visit HEAD OFFICE 1 Angel Lane London EC4R 3AB UK