Table of Contents   I. 5G Standardization so far II. 5G Developments in Leading Countries    1. Korea  1-1. KT  1-2. SK Telecom 1-3. LG U+   2. U.S. 2-1. Verizon 2-1. AT&T   3. Japan 3-1. NTT DoCoMo   4. China  4-1. China Mobile

 

 

 

II. 5G Developments in Leading Countries

 

 

1. Korea

 

As the average rates of their LTE subscription have stagnated (at 82.9% as of Q3 2016), South Korea's big 3 telcos are all aggressively seeking ways to develop new services and move forwards 5G.

 

 

Figure 1-1. Number of mobile connections in Korea (Q3 2016) 

 

KT, as a sponsoring telco of the PyeongChang Winter Olympic in 2018, is aiming to launch 5G trial service in time before the event begins, and then ultimately commercial 5G services in 2019. The telco developed 5G RAT common specifications with Verizon, a USA telco who is almost ready to present commercial 5G FWA services in 2017, while driving many global partnerships for 5G standardization. SK Telecom (SK Telecom), the strongest rival of KT, also introduced Quantum, its 5G brand, to the world in last November, taking the lead in global efforts for 5G development through conducting a demonstration of 'Connected Car', one of its  new Quantum solutions, and more. SK Telecom also declared that it would begin 5G trial service in the second half of the year and make itself ready to launch 5G commercial service by 2019. LG U+ is gearing up for 5G commercialization by 2020.      

 

 

1-1. KT

 

■ What's planned

KT aims to launch 5G trial service during the 2018 PyeongChang Olympic Games. With the experience to be gained from the service, the telco hopes to move forwards to present the world's first commercial, mobile 5G service in 2019, positioning itself as a leader in 5G standardization. The 5G trial service in 2018 will be based on the pre-standard specification because 5G global standards will not be available around 2020. As all the 5G systems that KT is currently developing for the 5G trial service are technically and fundamentally based on the pre-standard specifications, KT is working closely with global leading players in the field like global manufacturers and telcos to ensure that this specification is reflected in the final 5G standards as much as possible.

 

Simply put, KT's ultimate 5G strategy is to make the PyeongChang 5G technology a global and commercial 5G technology by:

• [2016] Develop a set of 5G common specifications (KT 5G-SIG specifications*) in partnership with global vendors
• [2018] Present commercial-level 5G trial service based on the KT 5G-SIG specification during the PyeongChang Winter Olympics
• [2017-2019] Have the KT 5G-SIG specification to be reflected in the 3GPP 5G standards as much as possible
• [2019] Upgrade 5G trial network to a commercial network that comply with 3GPP 5G NR standards
• [2019] Launch the world's first commercial 5G service

* Commonly known as, KT 5G specifications or PyeongChang 5G specifications

 

■ Progresses made and to be made

We will see 5G development made by KT so far as categorized in Figure 1-2 below.

 

 

Figure 1-2. KT 5G progress 

 

KT 5G Specifications

KT formed 'KT 5G-SIG' with global vendors (Samsung, Ericsson, Nokia, Intel and Qualcomm) in November 2015 and finalized the 'KT 5G-SIG’ specifications, the world’s first common specifications for 5G, in June 2016 (Figure 1-3). 5G.201 and 5G.211 - 5G.214 define RF/physical layer specifications while 5G.300, 5G.321 - 5G.323 and 5G.331 define higher layer protocol specifications.  

The telco, collaboratively with Verizon, completed development of common specifications for mmWave-based 5G RAT, and is also cooperating for SDN/NFV and GiGA Wire technologies. mmWave-based 5G and GiGA Wire will be adopted to be used for fixed wireless access and existing coaxial cable, respectively, to help deploy broadband Internet. 

 

 

Figure 1-3. KT 5G-SIG members and KT 5G-SIG specifications 

 

The KT 5G specifications, while primarily based on LTE specification and EPC, were designed to be 3GPP forward-compatible. <Table 1-1> and <Table 1-2> show key items defined in the KT 5G-SIG specifications. 

 

RF/Physical layer: The operating frequency band of KT 5G is 28 GHz (27.5 - 28.35 GHz) with up to 800 MHz bandwidth using 8x100 MHz carrier aggregation. A radio frame duration is 10 ms and each subframe period (or TTI) is 0.2 ms which consists of 14 OFDM symbols. KT 5G frame structure supports i) self-contained subframe which enables a DL data transmission and UL ACK in the same subframe and ii) dynamic TDD assignment which can dynamically change the UL and DL subframe ratios to cope with instantaneous traffic conditions. In the self-contained structure, each subframe keeps DL data in the front symbols and UL ACK in the back symbol. KT 5G radio supports hybrid beamforming which can combine the advantage of both analog and digital beamforming. 8 MIMO streams per cell and 2 MIMO streams per UE are supported.

 

<Table 1-1> KT 5G-SIG specifications: RF/Physical layer

 

(source: KT, presented at Mobile Communication Technology Workshop by KICS, February 2017)

 

Network/Protocol: KT's transition to 5G network will be made based on EPC, in a way that minimize changes required in the core network. The KT's 5G network can be SW upgraded to reflect the updates/changes once 3GPP 5G standards are finalized in the future. It will be able to support both Non-standalone (NSA) and Standalone (SA) modes as being discussed in 3GPP (Currently, only SA mode is supported in Verizon network). The network, consisting of EPC and PyeongChang trial base station (P5G RAN), to be composed of LTE base stations (eNBs) and 5G base stations, will ensure seamless interworking between LTE and 5G.  

 

<Table 1-2> KT 5G-SIG specifications: Network/Protocol

 

(source: KT, presented at Mobile Communication Technology Workshop by KICS, February 2017)

 

Development/Test

Based on the specifications, KT built a 5G network testbed and completed mmWave channel modeling and field tests in 2015. In the second half of 2016, it introduced 5G systems and devices  (in partnership with Samsung, Ericsson, Nokia and Intel) based on the KT 5G specifications. Then, it performed a 5G e2e First Call test using the same specifications in October 2016, followed by interworking tests between base stations and devices a month later. Starting from October 2016, the telco has been conducting fields tests in select areas in Seoul and PyeongChang using the '5G test network' configured based on the KT 5G specifications. In the field tests conducted in Seoul in December 2016, inbuilding, handover, multi-vendor interoperability and more were tested, and inbuilding tests showed averages of 2.3 Gbps download speeds. Now it is carrying out field tests in PyeongChang.

• Oct. 2016: Performed, jointly with Samsung, 5G e2e First Call test based on the 'KT 5G-SIG' specifications
• Oct. 2016: Began 5G virtualized core network verification process with Samsung and Nokia
• Nov. 2016: Developed KT 5G-SIG base station with Ericsson and Nokia
• Nov. 2016: Performed first interworking tests between 5G base stations and 5G devices 
• Dec. 2016: Conducted field tests in downtown Seoul, supporting 5G indoor 2.3 Gbps (DL) and testing handovers
• Feb. 2017 ~ : Currently conducting field tests in the PyeongChang Olympic arena and village

 

 

(a) 5G e2e First Call Test (KT - Samsung)

 

(b) Ericsson 5G UE and BBU (left) and Nokia RFU (right)

Figure 1-4. KT 5G-SIG based 5G system 

 

 

Figure 1-5. KT 5G BUS: handover test 

 

5G Network Deployment

In November 2016, a test event titled 'Hello PyeongChang' started as a part of preparation efforts for the sport event and it will go on until April 2017. From the end of 2016 to March 2017, KT conducted a range of field tests in downtown Seoul (e.g. indoor performance and handover tests in last December) and PyeongChang (e.g. immersive services in actual sports events during February and March 2017). After that, the 5G trial network for the PyeongChang Olympic 5G trial service will be deployed in Pyeongchang, Jeongseon, Gangneung and other select areas in Seoul by September 2017. After the sports event, the 5G trial network will be upgraded and expanded to reflect the 3GPP Release 15 specifications, making it possible to deploy a real 5G commercial network in 2019.

• March 2017: KT 5G test network deployed in PyeongChang
• September 2017: KT 5G trial network deployment to be completed

 

5G Service Demonstration  

To demonstrate 5G trial service in preparation, KT conducted the 1st test event in February 2016, and the 2nd test event in February and March 2017 in PyeongChang. In December, 2016, a field test to demonstrate the upgraded service presented in the first test event was carried out as well.

 

1) 1st test event (in February 2016): Sync view, 360° VR, Hologram live, 5G Safety, Interactive multi-view (time slice), etc.

• Sync view - Streaming events from the perspectives of players
• 360° VR - Live streaming of events in real time through multi-channel  
• Interactive multi-view - e.g. Can be used in video replay by referees
• Hologram live
• 5G safety - Drone featuring face recognition solution integrated with AI system

 

 

Figure 1-6. 5G services demonstrated in the 1st test event (February 2016)

 

2) 5G field test demonstration (December 2016): Upgraded services tested in the 1st test event were demonstrated.

• Sync view - Live streaming from the perspective of a bobsleigh player running at the average speeds of 120-150 Km/hour
• Hologram - World's first multi-party hologram
• 360° VR - Offers upgraded views of arenas, waiting rooms and interview rooms
• Interactive multi-view - Provides views of each player, allowing viewers to keep tracks of their movement individually in a team sports game like ice hockey 

 

 

Figure 1-7. 5G Field test demonstration (Upgraded services tested in the 1st test event, December 2016)

 

3) 2nd test event (in March 2017)

In the ‘Hello PyeongChang’ event, various services including four key 5G immersive services, Sync View service, 360º VR service, Interactive Multi-View service, and Omni Point View service, were actually offered and tested in real games. In addition, 5G converged services, like Mixed Reality (MR)/Virtual Reality) (VR) service, 5G autonomous driving bus, drone delivery, were also demonstrated.

• Sync view – technically verified in actual games during the Bobsleigh World Cup held by International Bobsleigh Skeleton Federation (IBSF)
• 360° VR – technically verified in actual games during the Four Continents Figure Skating Championships held by International Skating Union (ISU) 
• Interactive multi-view - technically verified in actual games during the Four Continents Figure Skating Championships held by International Skating Union (ISU) 
• Omni point view - technically verified in actual games during the Cross Country World Cup held by International Ski Federation (FIS)
• Demonstration of MR torch relay and VR Walk Through  
• Demonstration of 5G autonomous driving bus and drone delivery
• Demonstration of hologram live in 5G autonomous driving bus 

 

 

Figure 1-8. Verification of four key 5G immersive services and demonstration of 5G converged services during the 2nd test event (February and March 2017)

 

■ Key radio access technologies

Some of KT’s key radio access technologies based on the KT 5G-SIG specifications are outlined below.

• mmWave - 5G-SIG system operates in 28GHz mmWave band using up to 800MHz bandwidth (through CA of eight (8) 100MHz channels). mmWave band has smaller cell coverage, but shorter wave length. This makes it possible to mount more antennas in the same footprint, allowing multiple antenna solutions to be adopted. 
• Hybrid beamforming - Can support both analog and digital beamforming
• Lean Design  - More efficient in minimizing control signals than LTE. Can improve data transmission speeds by fully utilizing radio resources. Reference signals and system information that are kept "always on" in LTE can be minimized.
• Self-contained structure - Radio frame that can process downlink data and uplink response in less than 1 ms is supported to meet the relevant 5G requirement.
• Dynamic TDD - Utilize radio resources in more efficient ways by adjusting UL/DL link rates in real-time depending on the amount of traffic or the nature of service being offered.
• 4G-5G interworking - The KT 5G-SIG specifications had it mandatory for devices to have dual connectivity that offers both LTE and 5G connections at the same time, and offer uninterrupted service through handovers between LTE and 5G. By default, control signals are transmitted via LTE and data are delivered via 5G.

 

 

Figure 1-9. Key radio access technologies

 

■ Key infrastructure technologies

Some of the key infrastructure technologies are:

• Network Virtualization - In KT's 5G system, mobile network/service functions run as SW on universal-purpose servers. Dedicated networks such as disaster network, IoT network, and traffic network are virtualized as SW solutions on universal, common HW equipment. This means a new network can be easily deployed through modifying the configuration of the network using SW on the existing network, and even customized as a dedicated network that meets an operator's business needs and facilitate introduction of application services. 
• Network distribution and SW-based control architecture - In 5G where capacity per cell reaches 20 Gbps, traffic must be distributed before they can be processed. Servers  (i.e. edge clouds) are distributed across the nation through SW virtualization, and network functions are placed on to the servers, effectively distributing traffic data. Resource allocation for virtualized network functions on the edge clouds are controlled by the orchestrator in the central location through SW.

 

■ 5G global collaboration activity

KT have been aggressively working with 5G standardization organizations, such as 3GPP and ITU, and 5G leading companies for establishment of KT 5G specifications. It has also teamed up with global leading vendors through 5G-SIG, 5G DF, NFV Open Lab, SDI Open Eco Alliance, etc. to pave ways to develop 5G system and deploy software-based networks.

 

<Table 1-3> 5G global collaboration activity

 

 

■ Other 5G services

Although, for now, KT's main focus is on successful launch of 5G trial service, the telco has showed keen interests in artificial intelligence and autonomous driving service technologies.

• Artificial Intelligence (AI) Service: In January 2017, KT launched an IPTV-based AI service with 'GiGA Genie', an voice/video-based AI set-top box (see Netmanias's blog).
• Autonomous driving service: Infrastructure for autonomous driving services requires high data throughput in order to link transmit data on road conditions in real time. KT has been taking the lead in building nationwide wired/wireless networks across the nation to realize the vision of 'GiGATopia' it had declared, and now with its strong wired infrastructure, it has secured competitive advantage in terms of infrastructure environment needed for autonomous driving service. Some of the technologies that it is currently investing are ITS/vehicle control, next generation telematics based on high precision position measurement, and eco-drive/electric car, vehicle entertainment based on 5G ultra-wideband network.

 

■ 5G roadmap 

 

Figure 1-10. KT 5G roadmap