Introduction to 5G ATSSS - Access Traffic Steering, Switching and Splitting

Last month we made a short tutorial on 5G and Fixed-Mobile Convergence (FMC). One of the features covered in that was ATSSS. It deserved a bit more detail so we made a short tutorial on this feature.

Access Traffic Steering, Switching and Splitting or ATSSS for short is being standardized as part of 3GPP Rel-16 and allows traffic steering across multiple accesses at a finer granularities than a PDU session.  It is an optional feature both on the UE and the 5GC network. ATSSS introduces the notion of Multi Access PDU session, a PDU session for which the data traffic can be served over one or more concurrent accesses (3GPP access, trusted non-3GPP access and untrusted non-3GPP access). The simplest way to visualize it is as shown below:

The presentation and video is embedded below:

Misc: Introduction to ATSSS - Access Traffic Steering, Switching and Splitting from 3G4G

Related Posts:

• Exploring Network Convergence of Mobile, Broadband and Wi-Fi
• 5G and Fixed-Mobile Convergence (FMC)
• BT's Converged Core to Launch in 2023
• Tutorial: Service Based Architecture (SBA) for 5G Core (5GC)
• Updated 5G Terminology Presentation (Feb 2019)

5G and Fixed-Mobile Convergence (FMC)

We recently made a new video looking at how 5G architecture caters for Trusted and Untrusted Wireless Access as well as Wireline Access. The presentation discusses:

• Untrusted non-3GPP access networks;
• Trusted non-3GPP access networks (TNAN);
• Wireline access networks;
• Non-5G-Capable over WLAN (N5CW);
• Access Traffic Steering, Switching and Splitting (ATSSS)

Slides and video embedded below.

Advanced: True Fixed-Mobile Convergence (FMC) with 5G from 3G4G

Related Posts:

• Exploring Network Convergence of Mobile, Broadband and Wi-Fi
• Introduction to 5G ATSSS - Access Traffic Steering, Switching and Splitting
• Operator Watch Blog: BT's Converged Core to Launch in 2023
• Tutorial: Service Based Architecture (SBA) for 5G Core (5GC)
• Updated 5G Terminology Presentation (Feb 2019)
• An Introduction to Non-Terrestrial Networks (NTN)
• 3G4G: 3GPP 5G Specifications
• 3G4G: 5G (IMT-2020) Wireless
• Opinion: What is "Real 5G" or "True 5G"
• The Politics of Standalone vs Non-Standalone 5G & 4G Speeds
• New 3GPP Release-17 Study Item on NR-Lite
• 5G SpeedTests and Theoretical Max Speeds Calculations

LTE / 5G Broadcast Evolution

It's been a while since I last wrote about eMBMS. A report by GSA last month identified:
- 41 operators known to have been investing in eMBMS
- 5 operators have now deployed eMBMS or launched some sort of commercial service using eMBMS
- GSA identified 69 chipsets supporting eMBMS, and at least 59 devices that support eMBMS

#eMBMS
- 41 operators known to have been investing in eMBMS
- 5 operators have now deployed eMBMS or launched some sort of commercial service using eMBMS
- GSA identified 69 chipsets supporting eMBMS, and at least 59 devices that support eMBMShttps://t.co/EjjOH1tQxy pic.twitter.com/Gcc35BFC8H

— GSA (@gsacom) August 6, 2019

BBC R&D are testing the use of 4G/5G broadcast technology to deliver live radio services to members of the public as part of 5G RuralFirst - one of 6 projects funded under the UK Government’s 5G Phase 1 testbeds and trials programme (link).

A press release by Samsung Electronics back in May announced that it has signed an expansion contract with KT Corporation (KT) to provide public safety (PS-LTE) network solutions based on 3GPP standard Release 13 for 10 major metropolitan regions in South Korea including Seoul by 2020. One of the features of PS-LTE that the PR listed was LTE Broadcast (eMBMS): A feature which allows real time feeds to hundreds of devices simultaneously. It enables thousands of devices to be connected at once to transfer video, images and voice simultaneously using multicast technology

Dr. Belkacem Mouhouche – Samsung Electronics Chief Standards Engineer  and Technical Manager of 5G projects: 5G-Xcast and 5G-Tours Presented an excellent overview on this topic at IEEE 5G Summit Istanbul, June 2019. His presentation is embedded below.

Recent advances in Broadcasting standards and research from 3G4G

5G-Xcast is a 5GPPP Phase II project focused on Broadcast and Multicast Communication Enablers For the Fifth Generation of Wireless Systems.

They have a YouTube channel here and this video below is an introduction to project and the problems it looks to address.




Further Reading:

• GSA Report: LTE Broadcast (eMBMS) Market Update – July 2019
• GSA Snapshot: LTE Broadcast – eMBMS – Snapshot July 2019

Related posts:

• The 3G4G Blog: Multicast Operation on Demand (MooD) and Service Continuity for eMBMS
• Operator Watch Blog: Telstra's LTE-B Push
• Operator Watch Blog: Reliance Jio getting ready for LTE-Broadcast (eMBMS) rollout
• The 3G4G Blog: Mission Critical Services update from 3GPP - June 2017

An Introduction to Non-Terrestrial Networks (NTN)

I made a short introductory tutorial explaining what is meant by Non-Terrestrial Networks. There is is lot of work on this that is planned for Release-17. Slides and video below.

Beginners: Non Terrestrial Networks (NTN) from 3G4G

Related Posts:

• Connectivity Technology Blog: TIP has launched 'Non-Terrestrial Connectivity Solutions' Group
• The 3G4G Blog: Connectivity on Planes
• The 3G4G Blog: Satellites & Non-terrestrial networks (NTN) in 5G
• 3G4G Small Cells Blog: Flying Small Cells are here...

3GPP 5G Standardization Update post RAN#84 (July 2019)

3GPP recently conducted a webinar with Balazs Bertenyi, Chairman of 3GPP RAN in which he goes through some of the key features for 5G Phase 2. The webinar also goes through the details of 5G Release-15 completion, status of Release-16 and a preview of some of Release-17 features.

Slides & video embedded below. Slides can be downloaded from 3GPP website here.

3GPP Webinar: 5G Standardization update from 3G4G

Related Posts:

• The 3G4G Blog - New 3GPP Release-17 Study Item on NR-Lite
• 3GPP Release-16, Release-17 & Beyond...
• Non-public networks (NPN) - Private Networks by another name
• Evolution of Security from 4G to 5G
• Update from 3GPP on LTE & 5G Mission Critical Communications
• Updated 5G Terminology Presentation (Feb 2019)

3GPP Release-16, Release-17 & Beyond...

6G Summit featured quite a few talks from people looking at evolution beyond Release-16. The future releases will still be 5G, maybe become 5.5G, like 3GPP Release-13 which was known as LTE-Advanced Pro officially was unofficially known as 4.5G.

Back at the 6G Summit in Finland, Dr. Peiying Zhu from Huawei looked at the topics being discussed for Release-17 and beyond.

Thanks to Mika Klemettinen for sharing the pictures on Twitter, as the presentation was not shared.

3GPP is working towards defining Release-16. TS 21.916 - Release description; Release 16 is still not yet available on the 3GPP reflector. Once that is available, we will know for sure about all the Rel-16 changes. Release-17 is long way away. Having said that, there is no shortage of discussions as some of these Rel-17 features were discussed in the recent RAN Plenary.

Jungwon Lee, VP, Samsung also shared a summary of 3GPP Release-16 and Rel-17 features at IEEE 5G Summit in San Diego recently. Quite a few interesting features in all the pictures above that we will no doubt look at in the future posts.

3GPP also shared a presentation recently (embedded below), looking at not only Release-15 & 16 but also looking at focus areas for Release-17

5G Standards: 3GPP Release 15, 16, and beyond from 3G4G

Related Posts and Articles:

• The 3G4G Blog - Ultra Reliability: 5x9s (99.999%) in 3GPP Release-15 vs 6x9s (99.9999%) in 3GPP Release-16
• The 3G4G Blog - Update from 3GPP on LTE & 5G Mission Critical Communications
• 3GPP - Release 16
• Light Reading - 5G Standards Group Struggles to Balance Tech With Politics
• Eiko Seidel - 5G Mission Critical Networks (Proximity Services in Rel.17)
• The 3G4G Blog - Slides and Videos from the 1st 6G Wireless Summit - March 2019
• The 3G4G Blog - Couple of talks by NTT Docomo on 5G and Beyond (pre-6G)
• The 3G4G Blog - China Telecom: An examination of the current industrial trends and an outlook of 6G
• Mission Critical Communications: Mission-Critical Features for Release 17 Discussed at Latest 3GPP Meetings

Ultra Reliability: 5x9s (99.999%) in 3GPP Release-15 vs 6x9s (99.9999%) in 3GPP Release-16

We made a tutorial some time back explaining how to calculate reliability and what is the difference between 5x9s in 3GPP Release-15 5G vs 6x9s in 3GPP Release-16. Slides and video below

Beginners: Reliability - 5x9s vs 6x9s from 3G4G

Related posts:

• Updated 5G Terminology Presentation (Feb 2019)
• Prof. Andy Sutton: 5G Radio Access Network Architecture Evolution - Jan 2019
• Theoretical Throughput Calculation of FDD 5G New Radio (NR)
• Can Augmented & Mixed Reality be the Killer App 5G needs?
• What is Industrial IoT (IIoT) and how is it different from IoT?

Update from 3GPP on LTE & 5G Mission Critical Communications

Adrian Scrase, CTO of ETSI & Head of MCC, 3GPP presented an update at BAPCO / CCE 2019 on Public Safety LTE and 5G. His presentation is embedded below.

There has been quite a progress in this area since I wrote my last post on Release-14 here.

This is the list of features that are planned for Release-16. There is also an update on Satellite communications but I will look at it separately in another post. Here are the slides:

Keynote Address: Critical communications standards supporting a multi-vendor and interoperable environment from 3G4G

The presentation can be directly downloaded from 3GPP website here.

Related posts:

• Update on UK's Emergency Services Network (ESN) from #BAPCO2019
• Tutorial on Network In a Box (NIB)
• Summary of 3GPP Release-14 Work Items

Automating the 5G Core using Machine Learning and Data Analytics

One of the new entities introduced by 3GPP in the 5G Core SBA (see tutorial here) is Network Data Analytics Function, NWDAF.

3GPP TR 23.791: Study of Enablers for Network Automation for 5G (Release 16) describes the following 5G Network Architecture Assumptions:

1 The NWDAF (Network Data Analytics Function) as defined in TS 23.503 is used for data collection and data analytics in centralized manner. An NWDAF may be used for analytics for one or more Network Slice.
2 For instances where certain analytics can be performed by a 5GS NF independently, a NWDAF instance specific to that analytic maybe collocated with the 5GS NF. The data utilized by the 5GS NF as input to analytics in this case should also be made available to allow for the centralized NWDAF deployment option.
3 5GS Network Functions and OAM decide how to use the data analytics provided by NWDAF to improve the network performance.
4 NWDAF utilizes the existing service based interfaces to communicate with other 5GC Network Functions and OAM.
5 A 5GC NF may expose the result of the data analytics to any consumer NF utilizing a service based interface.
6 The interactions between NF(s) and the NWDAF take place in the local PLMN (the reporting NF and the NWDAF belong to the same PLMN).
7 Solutions shall neither assume NWDAF knowledge about NF application logic. The NWDAF may use subscription data but only for statistical purpose.

Picture Source: Application of Data Mining in the 5G Network Architecture by Alexandros Kaloxylos

Continuing from 3GPP TR 23.791:

The NWDAF may serve use cases belonging to one or several domains, e.g. QoS, traffic steering, dimensioning, security.
The input data of the NWDAF may come from multiple sources, and the resulting actions undertaken by the consuming NF or AF may concern several domains (e.g. Mobility management, Session Management, QoS management, Application layer, Security management, NF life cycle management).
Use case descriptions should include the following aspects:
1. General characteristics (domain: performance, QoS, resilience, security; time scale).
2. Nature of input data (e.g. logs, KPI, events).
3. Types of NF consuming the NWDAF output data, how data is conveyed and nature of consumed analytics.
4. Output data.
5. Possible examples of actions undertaken by the consuming NF or AF, resulting from these analytics.
6. Benefits, e.g. revenue, resource saving, QoE, service assurance, reputation.

Picture Source: Application of Data Mining in the 5G Network Architecture by Alexandros Kaloxylos

3GPP TS 23.501 V15.2.0 (2018-06) Section 6.2.18 says:

NWDAF represents operator managed network analytics logical function. NWDAF provides slice specific network data analytics to a NF. NWDAF provides network analytics information (i.e., load level information) to a NF on a network slice instance level and the NWDAF is not required to be aware of the current subscribers using the slice. NWDAF notifies slice specific network status analytic information to the NFs that are subscribed to it. NF may collect directly slice specific network status analytic information from NWDAF. This information is not subscriber specific.

In this Release of the specification, both PCF and NSSF are consumers of network analytics. The PCF may use that data in its policy decisions. NSSF may use the load level information provided by NWDAF for slice selection.

NOTE 1: NWDAF functionality beyond its support for Nnwdaf is out of scope of 3GPP.
NOTE 2: NWDAF functionality for non-slice-specific analytics information is not supported in this Release of the specification.

3GPP Release-16 is focusing on 5G Expansion and 5G Efficiency, SON and Big Data are part of 5G Efficiency.

3GPP Release-16 is going to focus on 5G expansion & efficiency. Listen to the @3GPPLive Webinar here: https://t.co/tKzXJ3cUFj pic.twitter.com/1xCZfpT9lt

— 3G4G (@3g4gUK) July 14, 2018

Light Reading Artificial Intelligence and Machine Learning section has a news item on this topic from Layer123's Zero Touch & Carrier Automation Congress:

The 3GPP standards group is developing a machine learning function that could allow 5G operators to monitor the status of a network slice or third-party application performance.

The network data analytics function (NWDAF) forms a part of the 3GPP's 5G standardization efforts and could become a central point for analytics in the 5G core network, said Serge Manning, a senior technology strategist at Sprint Corp.

Speaking here in Madrid, Manning said the NWDAF was still in the "early stages" of standardization but could become "an interesting place for innovation."

The 3rd Generation Partnership Project (3GPP) froze the specifications for a 5G new radio standard at the end of 2017 and is due to freeze another set of 5G specifications, covering some of the core network and non-radio features, in June this year as part of its "Release 15" update.

Manning says that Release 15 considers the network slice selection function (NSSF) and the policy control function (PCF) as potential "consumers" of the NWDAF. "Anything else is open to being a consumer," he says. "We have things like monitoring the status of the load of a network slice, or looking at the behavior of mobile devices if you wanted to make adjustments. You could also look at application performance."

In principle, the NWDAF would be able to make use of any data in the core network. The 3GPP does not plan on standardizing the algorithms that will be used but rather the types of raw information the NWDAF will examine. The format of the analytics information that it produces might also be standardized, says Manning.

Such technical developments might help operators to provide network slices more dynamically on their future 5G networks.

Generally seen as one of the most game-changing aspects of 5G, the technique of network slicing would essentially allow an operator to provide a number of virtual network services over the same physical infrastructure.

For example, an operator could provide very high-speed connectivity for mobile gaming over one slice and a low-latency service for factory automation on another -- both reliant on the same underlying hardware.

However, there is concern that without greater automation operators will have less freedom to innovate through network slicing. "If operators don't automate they will be providing capacity-based slices that are relatively large and static and undifferentiated and certainly not on a per-customer basis," says Caroline Chappell, an analyst with Analysys Mason .

In a Madrid presentation, Chappell said that more granular slicing would require "highly agile end-to-end automation" that takes advantage of progress on software-defined networking and network functions virtualization.

"Slices could be very dynamic and perhaps last for only five minutes," she says. "In the very long term, applications could create their own slices."

Despite the talk of standardization, and signs of good progress within the 3GPP, concern emerged this week in Madrid that standards bodies are not moving quickly enough to address operators' needs.

Caroline Chappell's talk is available here whereas Serge Manning's talk is embedded below:



I am helping CW organise the annual CW TEC conference on the topic The inevitable automation of Next Generation Networks

#CWTEC 2018 planning committee working hard to bring an exciting conference - explores the role of #AI in delivering Next Gen. Network performance; & bridges the gap between #AI/#ML & Telecos communities! @zahidtg @Bob_CWCEO @swunger Paul Ceely @bt_uk , John Haine @BristolCSN pic.twitter.com/4uGprC1usg

— Sylvia Lu (@SylviaLuUk) July 23, 2018

Communications networks are perhaps the most complex machines on the planet. They use vast amounts of hardware, rely on complex software, and are physically distributed over land, underwater, and in orbit. They increasingly provide essential services that underpin almost every aspect of life. Managing networks and optimising their performance is a vast challenge, and will become many times harder with the advent of 5G. The 4th Annual CW Technology Conference will explore this challenge and how Machine Learning and AI may be applied to build more reliable, secure and better performing networks.

Is the AI community aware of the challenges facing network providers? Are the network operators and providers aware of how the very latest developments in AI may provide solutions? The conference will aim to bridge the gap between AI/ML and communications network communities, making each more aware of the nature and scale of the problems and the potential solutions.

I am hoping to see some of this blog readers at the conference. Looking forward to learning more on this topic amongst others for network automation.

Related Post:

• Artificial Intelligence - Beyond SON for Autonomous Networks

enhanced Public Warning System (ePWS) in 3GPP Release-16

I wrote about PWS 9 years back here. Since then there has been little chance to PWS until recently. According to 3GPP News:

Additional requirements for an enhanced Public Warning System (ePWS) have been agreed at the recent 3GPP TSG SA#79 meeting, as an update to Technical Specification (TS) 22.268.

3GPP Public Warning Systems were first specified in Release 8, allowing for direct warnings to be sent to mobile users on conventional User Equipment (PWS-UE), capable of displaying a text-based and language-dependent Warning Notification.

Since that time, there has been a growth in the number of mobile devices with little or no user interface - including wrist bands, sensors and cameras – many of which are not able to display Warning Notifications. The recent growth in the number of IoT devices - not used by human users – also highlights the need for an alternative to text based Warning Notifications. If those devices can be made aware of the type of incident (e.g. a fire or flood) in some other way than with a text message, then they may take preventive actions (e.g. lift go to ground floor automatically).

3GPP SA1 delegates also considered how graphical symbols or images can now be used to better disseminate Warning Notifications, specifically aimed at the following categories of users:

• Users with disabilities who have UEs supporting assistive technologies beyond text assistive technologies; and
• Users who are not fluent in the language of the Warning Notifications.

Much of the work on enhancing the Public Warning System is set out in the ePWS requirements specification: TS 22.268 (SA1). You should also keep an eye on the 3GPP protocol specifications (CT1, Stage 3 work) in Release 16, covering:

• Specifying Message Identifiers for ePWS-UE, especially IoT devices that are intended for machine type communications
• Enabling language-independent content to be included in Warning Notifications

The work on ePWS in TS 22.268 (Release 16) is expected to help manufacturers of User Equipment meet any future regulatory requirements dedicated to such products.

Related Specs:

• 3GPP TR 22.869: Feasibility study on enhancements of Public Warning System; Stage 1
• 3GPP TS 22.268: Public Warning System (PWS) requirements - Stage 1 for Public Warning System
• 3GPP TS 23.041: Technical realization of Cell Broadcast Service (CBS) - CT1 aspects of Stage 3 for Public Warning System 
• 3GPP TS 29.168: Cell Broadcast Centre interfaces with the Evolved Packet Core; Stage 3 - CT4 aspects of Stage 3 for Public Warning System

Further reading:

• 3GPP: Towards a better Public Warning System (ePWS)
• 3G4G Blog: Public Warning System (PWS) in Release-9

Tutorial: Service Based Architecture (SBA) for 5G Core (5GC)

As a continuation of 'Control and User Plane Separation of EPC nodes (CUPS) in 3GPP Release-14', here is another tutorial on Service Base Architecture (SBA) for the 5G Core.

The slides (with video) is embedded below but there are quite a few tutorials on 5G available on 3G4G page here.

Advanced: 5G Service Based Architecture (SBA) from 3G4G

Further Reading:

• Control and User Plane Separation of EPC nodes (CUPS) in 3GPP Release-14
• 3GPP 5G Specifications
• 5G - 3G4G Webpage
• 2G, 3G, 4G & 5G Training and Tutorial Videos - 3G4G Webpage

QUIC - Possibly in 5G, 3GPP Release-16

Over the last year or so, I have heard quite a few discussions and read many articles around why QUIC is so good and why we will replace TCP with QUIC (Quick UDP Internet Connection). One such article talking about QUIC benefits says:

QUIC was initially developed by Google as an alternative transport protocol to shorten the time it takes to set up a connection. Google wanted to take benefits of the work done with SPDY, another protocol developed by Google that became the basis for the HTTP/2 standard, into a transport protocol with faster connection setup time and built-in security. HTTP/2 over TCP multiplexes and pipelines requests over one connection but a single packet loss and retransmission packet causes Head-of-Line Blocking (HOLB) for the resources that were being downloaded in parallel. QUIC overcomes the shortcomings of multiplexed streams by removing HOLB. QUIC was created with HTTP/2 as the primary application protocol and optimizes HTTP/2 semantics.

What makes QUIC interesting is that it is built on top of UDP rather than TCP. As such, the time to get a secure connection running is shorter using QUIC because packet loss in a particular stream does not affect the other streams on the connection. This results in successfully retrieving multiple objects in parallel, even when some packets are lost on a different stream. Since QUIC is implemented in the userspace compared to TCP, which is implemented in the kernel, QUIC allows developers the flexibility of improving congestion control over time, since it can be optimized and better replaced compared to kernel upgrades (for example, apps and browsers update more often than OS updates).

Georg Mayer mentioned about QUIC in a recent discussion with Telecom TV. His interview is embedded below. Jump to 5:25 for QUIC part only

Georg Mayer, 3GPP CT work on 5G from 3GPPlive on Vimeo.

Below are some good references about QUIC in case you want to study further.

• IETF QUIC Charter
• Youtube: QUIC Next generation multiplexed transport over UDP - Google
• Understanding QUIC wire protocol - Anuradha Niroshan
• HTTP/2 and QUICK protocols. Optimizing the Web stack for HTTP/2 era
• Measuring QUIC vs TCP on mobile and desktop

3GPP-VRIF workshop on Virtual Reality Ecosystem & Standards in 5G

Its been a year since I last posted about Augmented / Virtual Reality Requirements for 5G. The topic of Virtual Reality has since made good progress for 5G. There are 2 technical reports that is looking at VR specifically. They are:

• 3GPP TR 26.918: Virtual Reality (VR) media services over 3GPP
• 3GPP TR 26.929: QoE parameters and metrics relevant to the Virtual Reality user experience

The second one is work in progress though. 

Anyway, back in Dec. 3GPP and Virtual Reality Industry Forum (VRIF) held a workshop on VR Ecosystem & Standards. All the materials, including agenda is available here. The final report is not there yet but I assume that there will be a press release when the report is published.

While there are some interesting presentations, here is what I found interesting:

From presentation by Gordon Castle, Head of Strategy Development, Ericsson

From presentation by Martin Renschler, Senior Director Technology, Qualcomm

For anyone wanting to learn more about 6 degrees of freedom (6- DoF), see this Wikipedia entry. According to the Nokia presentation, Facebook’s marketing people call this “6DOF;” the engineers at MPEG call it “3DOF+.”

XR is 'cross reality', which is any hardware that combines aspects of AR, MR and VR; such as Google Tango.

From presentation by Devon Copley, Former Head of Product, Nokia Ozo VR Platform

Some good stuff in the pres.

From presentation by Youngkwon Lim, Samsung Research America; the presentation provided a link to a recent YouTube video on this presentation. I really liked it so I am embedding that here:



Finally, from presentation by Gilles Teniou, SA4 Vice chairman - Video SWG chairman, 3GPP

You can check and download all the presentations here.

Further Reading:

• 3GPP 5G Specifications

Satellites & Non-terrestrial networks (NTN) in 5G

Satellites has been an area of interest of mine for a while as some of you know that I used to work as Satellite Applications & Services Programme manager at techUK. I have written about how I see satellites complementing the mobile networks here and here.

Pic Source: The Role of Satellite in 5G - SES

Its good to see that there is some activity in 3GPP going on about satellites & Non-terrestrial networks (NTN) in 5G. While there are some obvious roles that satellites can play (see pic above), the 5G work is looking to cover a lot more topics in details.

Pic Source: Nomor - Overview 3GPP 5G Satellite Activities, Oct 2017

3GPP TR 38.913: Study on scenarios and requirements for next generation access technologies looks at 12 different scenarios, the ones relevant to this topic ate Air to ground, Light aircraft and Satellite to terrestrial.

3GPP TR 38.811: Study on New Radio (NR) to support non terrestrial networks (Release 15) covers this topic a bit more in detail. From looking at how satellites and other aerial networks work in general, it looks at the different NTN architecture options as can be seen above.

People looking to study this area in detail should probably start looking at this TR first.

3GPP also released a news item on this topic last week. It also refers to the above TR and a new one for Release 16. The following from 3GPP news:

The roles and benefits of satellites in 5G have been studied in 3GPP Release 14, leading to the specific requirement to support satellite access being captured in TS 22.261 - “Service requirements for next generation new services and markets; Stage 1”, recognizing the added value that satellite coverage brings, as part of the mix of access technologies for 5G, especially for mission critical and industrial applications where ubiquitous coverage is crucial.

Satellites refer to Spaceborne vehicles in Low Earth Orbits (LEO), Medium Earth Orbits (MEO), Geostationary Earth Orbit (GEO) or in Highly Elliptical Orbits (HEO).

Beyond satellites, Non-terrestrial networks (NTN) refer to networks, or segments of networks, using an airborne or spaceborne vehicle for transmission. Airborne vehicles refer to High Altitude Platforms (HAPs) encompassing Unmanned Aircraft Systems (UAS) - including tethered UAS, Lighter than Air UAS and Heavier than Air UAS - all operating at altitude; typically between 8 and 50 km, quasi-stationary.

These Non-terrestrial networks feature in TSG RAN’s TR 38.811 “Study on NR to support non-terrestrial networks”. They will:

• Help foster the 5G service roll out in un-served or underserved areas to upgrade the performance of terrestrial networks
• Reinforce service reliability by providing service continuity for user equipment or for moving platforms (e.g. passenger vehicles-aircraft, ships, high speed trains, buses)
• Increase service availability everywhere; especially for critical communications, future railway/maritime/aeronautical communications
• Enable 5G network scalability through the provision of efficient multicast/broadcast resources for data delivery towards the network edges or even directly to the user equipment

The objective of TR 38.811 is to study channel models, to define the deployment scenarios as well as the related system parameters and to identify and assess potential key impact areas on the NR. In a second phase, solutions for the identified key impacts on RAN protocols/architecture will be evaluated and defined.

A second study item, the “Study on using Satellite Access in 5G” is being addressed in Working Group SA1.  It shall lead to the delivery of the corresponding Technical Report TR 22.822 as part of Release 16.

This study will identify use cases for the provision of services when considering the integration of 5G satellite-based access components in the 5G system. When addressing the integration of (a) satellite component(s), use cases will identify new potential requirements for 5G systems addressing:

• The associated identification of existing / planned services and the corresponding modified or new requirements
• The associated identification of new services and the corresponding requirements
• The requirements on set-up / configuration / maintenance of the features of UE’s when using satellite components related features as well for other components from the 5G system
• Regulatory requirements when moving to (or from) satellite from (or to) terrestrial networks

Related Posts:

• An Introduction to Non-Terrestrial Networks (NTN)
• Connectivity on Planes
• Connectivity Technology Blog: TIP has launched 'Non-Terrestrial Connectivity Solutions' Group
• 3G4G Small Cells Blog: Flying Small Cells are here...

Updates from the 3GPP RAN 5G Workshop - Part 1

3GPP held a 5G Workshop in Phoenix last week. 550 delegates and over 70 presentations contributed to the discussion, which covered the full range of requirements that will feed TSG RAN work items for the next five years. I will eventually look at all the presentations and highlight the ones that I find interesting as a part of this blog. Due to the vast number of presentations, I will split them into a few blog posts.

Lets start with the chairman summary. The chair highlighted three high level use cases that 5G needs to address (This has been highlighted in many presentations, see here for example):

• Enhanced Mobile Broadbandare 
• Massive Machine Type Communications
• Ultra-reliable and Low Latency Communications

As can be seen in the picture above, 3GPP is planning to split the 5G work into two phases. Phase 1 (Rel-15) will look at a subset of requirements that are important for the commercial needs of the day. Phase 2 (Rel-16) will look at more features, use cases, detailed requirements, etc.

Here is the chair summary of the workshop:

The presentation (RWS-150002) from Motorola/Lenovo highlighted the need to handle different spectrum. For sub-6GHz, the existing air interface could work with slight modifications. For spectrum between 6GHz and 30GHz, again a similar air interface like 4G may be good enough but for above 30GHz, there is a need for new one die to phase noise.

The presentation by CATT or China Academy of Telecommunication Technology (RWS-150003) is quite interesting and is embedded below. They also propose Pattern Division Multiple Access (PDMA).

Orange (RWS-150004) has definitely put a thought into what good 5G would be. Their presentation is embedded below too:

The presentation from Huawei (RWS-150006) introduced the concept of Unified Air Interface, UAI.



They presentation also explains the concept of Adaptive Frame structures and RAN slicing very well. For those who may be wondering, uMTC stands for ultra-reliable MTC and mMTC stands for massive MTC. RAN slicing enables the RAN to be partitioned such that a certain amount of carriers are always dedicated to a certain services independently of other services. This ensures that the service in the slice is always served reliably.

The final presentation is the vision and priorities by 5GPPP as follows: