After months of discussions and deliberations, the scope of 5G Advanced Release 19 was approved at the 3GPP’s Plenary Meeting in Edinburgh in December. Led by Wanshi Chen, Chair of 3GPP TSG RAN, Release 19 builds on Release 18 and focuses on enhancing 5G performance while expanding the capability of 5G across devices and deployments. In addition, it will establish the technical foundations for 6G and will include preliminary work on new 6G capabilities.

Release 19 will be followed by Release 20, the first 3GPP release for 6G studies. During the next few years, 5G Advanced will continue to evolve within 3GPP while the standardization of 6G officially starts to ramp up in parallel. Release 18 is expected to be finalized in mid-2024 with Release 19 following in late 2025.

Performance Enhancements

5G Advanced continues to push the spectral efficiency limits and coverage in both sub-7GHz and millimetre wave spectrum. In addition to continued enhancements to massive MIMO radios and mobility, Release 19 provides advancements for new use cases such as XR and Non-Terrestrial Networks.

• Massive MIMO Radio - Release 18 introduced improvements to massive MIMO uplink and downlink throughput. Release 19 will boost capacity further by improving multi-user MIMO, which enables more UEs to share the same time and frequency resources.
  Release 19 will also enable the cost-efficient realization of distributed transmitters and receivers, thus improving signal quality. This is an important step towards enabling fully distributed MIMO (D-MIMO) systems. Other enhancements include 5G beam management with UE-initiated measurement reporting, thus resulting in faster beam selection.
• Mobility - 5G Advanced introduces a new handover procedure known as low-layer (i.e. L2) triggered mobility (LTM). In Release 18, LTM is supported between cells served by the same gNB. In Release 19, the LTM framework will be extended to support handover between cells served by different gNBs.
• XR and the Metaverse - Release 19 builds on the low latency and power saving features of Release 18 by enabling higher XR capacity by adding improved uplink and downlink scheduling using packet delay information.
• Non-Terrestrial Networks - 5G Advanced combines terrestrial and satellite communications under one standard for the first time. Release 19 will build on the enhancements introduced in Release 18 with a focus on increasing satellite downlink coverage, introducing UEs with higher output power and providing Redcap device support. It will also investigate whether additional support is required for regenerative payloads.

With a long history as an innovator in satellite communications, San Diego-based Qualcomm is leading the charge in non-terrestrial networking. In addition to its contributions to 5G NR NTN and 5G IoT NTN standards, the vendor recently launched two modems: the 212S modem, a satellite-only IoT modem and the 9205S modem. The latter connects to both terrestrial cellular and satellite networks and includes a Global Navigation Satellite Systems (GNSS) chip to provide location data.

Role of AI/ML in 5G Advanced

AI/ML will become a key feature of 5G networks with numerous applications ranging from network planning and network operations optimization to full network automation. Another important application is the use of AI/ML to improve the performance and functionality of the 5G air interface.

3GPP studied the use of AI/ML in the air interface in Release 18 and defined three use cases: channel state feedback (CSF) information, beam management and positioning. Based on the conclusions of Release 18 studies, Release 19 will specify a general AI/ML framework, i.e. actual specifications to support the above three use cases as well as specific support for each individual use case. Release 19 will also explore new areas in the AI/ML air interface such as mobility improvement and AI/ML-related model training, model management and global 5G data collection.

AI/ML is another major focus for Qualcomm. The company has dedicated significant technical resources to develop full-scale demonstrations of the three Release 18 defined use cases. For example, it recently demonstrated CSF-based cross-node machine learning involving E2E optimization between devices and the network. This reduces device communication overheads resulting in improved capacity and throughput. Qualcomm has also demonstrated the use of AI/ML to improve beam prediction on its 28GHz massive MIMO test network and is heavily involved in positioning technologies. For example, it has showcased its outdoor precise positioning technology, which uses multi-cell roundtrip (RTT) and angle-of-arrival (AoA) based technologies, as well as its RF finger printing technology operating in an indoor industrial private network.

Over the next few months, 3GPP will continue exploring the applicability of AI/ML based solutions for other use cases such as load balancing between cells, mobility optimization and network energy savings. For example, there will be support for conditional Layer 2 mobility in Release 19 and a new study item targeting new use cases designed to improve coverage and capacity optimization, such as AI-assisted dynamic cell shaping.

Enhancing Device and Network Sustainability

5G Advanced focuses on sustainability and introduces energy-saving features for devices and networks as well as exploring end-to-end energy saving opportunities that benefit devices. There are also improved features for RedCap and the study of ambient IoT as a new device type.

• Power-optimized devices - Releases 18 and 19 build on existing energy saving features, for example, a new low-power wakeup signal (LP-WUS). A low-complexity, power-optimized receiver is specified to monitor low-power wake-up signals from the network which only wakes-up the main radio when data is available at the device. This avoids the significant power consumption required to keep the main radio monitoring control signals from the network.
• Ambient IoT - enables new use cases enabled by very-low power devices that harvest energy from the ambient environment, for example, RF waves. Release 19 will investigate new architectures for ambient IoT devices and will include the development of a harmonized specification. Numerous use cases will be studied, including smart agriculture, industrial wireless sensor networks, smart logistics, warehousing, etc.
• Network energy savings - 5G Advanced reduces network energy consumption by dynamically adjusting the network’s operation based on feedback from the device, i.e. shutting down parts of the network when idle and transmitting less power depending on the overall traffic load or using more efficient antennas.

Setting The Stage For 6G

Although Release 19 will be the last release focused on 5G, it will also include some longer-term technologies that will become the foundation of 6G, thus setting the direction for Release 20. For example, Integrated Sensing and Communications (ISAC), which combines wireless communications with RF sensing, will enable a raft of new position-based use cases. Release 19 will study channel characteristics suitable for the sensing of various objects, including vehicles, UAVs and humans. Full duplex, another 6G technology, allows  transmitters and receivers to operate simultaneously on the same frequency, potentially resulting in a doubling of network capacity. Release 19 will study sub-band full duplex, a type of full duplex, which will improve capacity and latency, particularly for the uplink. Release 19 will also include channel model studies for the upper mid-band spectrum (7-16GHz), which will be supported by “Giga-MIMO” in the 6G timeframe, in order to enable wide-area coverage in this higher band.

Whereas AI/ML is a key pillar of 5G Advanced, it will be a core foundational technology of 6G and will underpin the key features that will make 6G revolutionary. For example, 6G will start to move away from the traditional, model-driven approach of designing communication systems and transition towards a more data-driven design. Indeed, it is likely that the 6G air-interface will be designed to be AI-native from the outset, thus signalling a paradigm change in the way communication systems are designed.  An AI-native air interface could offer many benefits. For example, it could refine existing communication protocols by continuously learning and improving them, thereby enabling the air interface to be customized dynamically to suit local radio environments.

Analyst Viewpoint

Despite huge investments in 5G, network operators are still reliant on revenues from traditional voice and broadband data services and are struggling to increase ARPU. Clearly, operators will need to leverage the capabilities of 5G Advanced in order to realize the full potential of 5G.

Although Release 19 includes a focus on new 6G focused technologies, Counterpoint Research believes that 5G is currently only at the midpoint of its development. Over the next few years, 5G Advanced will offer a plethora of new features to improve device and network capabilities and lower OPEX costs. It will also offer innovative new use cases thus enabling operators to generate new revenue streams. Together, this should enable operators to drive up ARPU of existing customers, lower OPEX costs and to acquire new B2B customers across several verticals.

However, 5G Advanced requires operators to deploy 5G SA cores across their networks. While around 92% of all 5G devices support 5G SA, only 21% of operators have started to invest in 5G SA. Of these, only 47 have commercially deployed 5G SA cores in their networks to date[1]. In the short-term, operators need to urgently prioritize 5G SA core deployment in order to fully benefit from their 5G investments.

[1] Source: GSA, 5G Standalone, October 2023

This blog is sponsored by Qualcomm.