In this report, the analyst highlights the industry’s current thinking on Release 18 5G NR functionality, better known as 5G NR Advanced.
Although the “final decisions” on Release 18 activities won’t be made until December with Release 18 activities currently scheduled to last 18 months - functionality won’t be commercialized until at least 2025 - it is helpful to understand where operators and vendors from around the world have some common beliefs on what is needed in the standard.
- No mention of LTE. When 3GPP held its first 5G workshop back in 2015 there was discussion on future LTE functionality. Not this time around, suggesting future LTE work will be specific to bug fixes and modifications needed to support the evolution of 5G NR.
- Give me an “e” or an “fe”. Most everything proposed in Release 18 is an enhanced (“e”) or further enhanced “fe”) implementation of something that already exists in the standard. There was even a “fee” or further enhanced and evolved proposal.
- More efficient RAN. Dozens of proposals dealt with improvements to the radio access network for both FR1 and FR2 (mmWave) - the latter included support from multiple operators. Better scheduling, improved MIMO and, especially, improvements to uplink coverage and capacity topped the list.
- Bring out the verticals. Non-terrestrial Networks (NTN) was a hot topic as was IIOT (Industrial IOT) and broadcast/multicast, although none of these topics has seen much in the way of commercialization as of now.
- Scheduling (Full Duplex, Cross Scheduling, Flexible Duplex)
- MIMO and Modulation Scheme Enhancements
- Uplink Performance (Transmit Power, Remote UEs)
- DSS Enhancements
- Mobility Enhancements
- Network Energy Efficiency
- Higher Frequencies
- Non-Terrestrial Networks
- Industrial IoT (IIoT) and URLLC
- Final Thoughts
List of Figures
Figure 1. Flexible Duplex Scheme with TDD
Figure 2. TDD and Carrier Aggregation versus Flexible Duplex/Full Duplex
Figure 3. Cross Carrier Scheduling
Figure 4. Distributed MIMO
Figure 5. Distributed Uplink MIMO
Figure 6. Simultaneous Uplink
Figure 7. Uplink Dynamic Power Aggregation
Figure 8. Flexible Spectrum Access
Figure 10. FR1 and FR2 CA/DC Operation for High Throughput URLLC
In September 2015, the analyst attended the 3GPP 5G Workshop, in which several hundred individuals from around the world shared their vision for 5G. Ironically, one of the big misses from the workshop was the timing of 5G. Seemingly no one, other than operators in South Korea and Japan, expected 5G to see the light of day before 2020, or in time for the summer Olympics. KT promoted its plans for a 5G network at the winter Olympics, and while there ended up being a network in place for the event, it was really just a trial/showcase network that provided limited benefits to attendees. No one at the time ever envisioned there being nationwide/ near nationwide 5G networks across multiple countries, including the use of both sub 6 GHz and mmWave frequencies. Then again, no one could have predicted that the Tokyo Olympics would take place in 2021 and that international spectators would be banned from attending.
For the last few weeks, 3GPP RAN has been holding a virtual meeting to initially plan the functionality for Release 18, better known as 5G Advanced. Although the scope for Release 18 won’t be finalized until December (further changes to increase/decrease scope are likely if consistent with previous releases), the stage is being set to define Release 18 functionality. As a bit of more irony, some of the proposed Release 18 functionality was originally proposed at the initial 5G workshop, meaning this functionality has still not made it into the standard. Therefore, readers shouldn’t assume that just because the analyst highlights something in this report, doesn’t mean it will make it into the forthcoming release. Presently, Release 18 activities, once they commence, will last for eighteen months with the commercialization of the functionality not anticipated until circa 2025 at the earliest.
Following this virtual meeting, 3GPP will commence a week of additional email discussions on the topics presented at this recent virtual workshop. The goal is to discuss these topics further so that the 3GPP Release 18 scope can be realistic. It is also foreseeable that topics not yet presented or discussed could make their way into the release - it has happened before. The RAN chairman identified 13 primary topics as well as 4 additional catch-all topics. The analyst addresses many of these topics in this report, although our grouping of topics doesn’t necessarily align with the chairman’s guidance since the analyst started work on this report well before the workshop finished. Unlike the 3GPP workshop, there was no mention of LTE when planning Release 18 functionality. One can rightfully conclude that new LTE functionality is unlikely other than necessary changes to support new 5G NR features and/or fix LTE bugs.
As another important caveat, there were 500+ initial submissions with many companies making multiple submissions. The analyst can’t claim to have reviewed every submission, but they did try to review as many submissions as possible, especially from those companies who have historically taken a leadership role in 3GPP, not to mention submissions with titles that appeared more interesting to us. Many companies proposed similar functionality, such as higher modulation schemes, more advanced MIMO schemes, etc. The analyst tried to give all companies as much credit as possible but ultimately, they're sure they unintentionally excluded one or more companies for the features that they are highlighting in this report. Lastly, the analyst notes that many of the proposed ideas pertain to study items, meaning that even if a proposed idea makes its way into Release 18, it may not become a commercial reality until Release 19. Even then, the Release 19 functionality may not be sufficient enough to entice operators to deploy it. For example, eMBMS (LTE Broadcast) went through a few releases before operators became interested in it, before subsequently dismissing the feature.