ITU Sets Framework for Future 6G Mobile Broadband Standard

The International Telecommunication Union (ITU) has today published the first framework for the future 6G mobile (mobile broadband) and wireless networking technology (IMT-2030), which will support the development of related standards and radio interface technologies. The framework also reveals more about its potential capabilities.

At present the 6G standard is still in the early R&D phase and most observers don’t expect to see the first commercial builds until around 2030 (some countries expect field trials in 2028). But in the recent past there has been talk of it aiming for theoretical peak data rates of up to 1Tbps (Terabits per second) – or 1,000Gbps (Gigabits) – and harnessing radio spectrum up to the TeraHertz (THz) bands, while also using AI optimisations, new antenna designs and changes to boost network efficiency.

However, hitting such speeds in the real-world is a much bigger challenge, due to various reasons, such as the highly variable mobile environment (weather, buildings, trees and device choice all impact signal quality). Not to mention the high cost of needing to deploy an extremely dense and complex network, which is needed to help overcome the huge problems with weak signals and other obstacles (e.g. building lots of masts often upsets people).

In addition, many mobile operators, such as Three UK, Vodafone, EE (BT) and O2 (VMO2), still prefer to harness lower frequencies in order to ensure good coverage and greater economic viability. Mobile bands in higher frequencies are generally weaker and don’t travel as far, but they can carry more data due to an excess of spectrum frequency (good for urban areas and fixed wireless links).

What’s in the ITU’s 6G Framework?

The details of the 6G framework are contained in Recommendation ITU-R M.2160 on the “IMT-2030 Framework” approved by the ITU Radiocommunication Assembly (RA-23) at its recent meeting in Dubai, United Arab Emirates. However, the framework isn’t so much a standard as a guide to help explain – very roughly – what 6G aims to achieve, as well as the kind of changes that may be necessary to deliver on that.

Mario Maniewicz, Director of the ITU Radiocommunication Bureau

“Terrestrial wireless systems to be developed under IMT-2030 are expected to drive the next wave of innovative radiocommunication systems, promote digital equity and advance universal connectivity. The publication of the Recommendation on future 6G mobile technologies is a testament to ITU’s longstanding multi-stakeholder approach which ensures the development of globally accepted technical and regulatory solutions.”

The reality is that we’ll have to wait until the first draft standards before being able to get a fuller idea of what 6G will aim to deliver over its lifespan (the top performance could take years to achieve post-deployment), but the new framework does at least provide some very rough hints. For example, it confirms that IMT-2030 is envisaged to utilize a wide range of frequency bands ranging from sub-1 GHz up to frequency bands above 100GHz.

A series of propagation measurement activities are currently being carried out in frequencies above 100GHz under several different environments (such as outdoor urban and indoor office). The ITU-R is currently developing a report on the technical feasibility of IMT technologies in bands above 92GHz, including coverage, link budget, mobility, impact of bandwidth and needed capabilities to support new use cases of IMT.

The framework also includes some estimated targets for research and investigation of IMT-2030, which are naturally aiming for something a fair bit greater than that of IMT-2020 (5G). We’ve pasted some of the most relevant bits of information below.

Potential Capabilities of IMT-2030

1) Peak data rate

Maximum achievable data rate under ideal conditions per device.

Values of 50, 100, 200 Gbit/s are given as possible examples applicable for specific scenarios, while other values may also be considered.

2) User experienced data rate

Achievable data rate that is available ubiquitously across the coverage area to a mobile device.

Values of 300 Mbit/s and 500 Mbit/s are given as possible examples, while other values greater than these examples may also be explored and considered accordingly.

3) Spectrum efficiency

Spectrum efficiency refers to average data throughput per unit of spectrum resource and per cell.

Values of 1.5 and 3 times greater than that of IMT-2020 could be a possible example, while other values greater than these examples may also be explored and considered accordingly.

4) Area traffic capacity

Total traffic throughput served per geographic area.

Values of 30 Mbit/s/m2 and 50 Mbit/s/m2 are given as possible examples, while other values greater than these examples may also be explored and considered accordingly.

5) Connection Density

Total number of connected and/or accessible devices per unit area.

The research target of connection density could be 106 – 108 devices/km2.

6) Mobility

Maximum speed, at which a defined QoS and seamless transfer between radio nodes which may belong to different layers and/or radio access technologies (multi-layer/multi-RAT) can be achieved.

The research target of mobility could be 500 – 1 000 km/h.

7) Latency

Latency over the air interface refers to the contribution by the radio network to the time from when the source sends a packet of a certain size to when the destination receives it.

The research target of latency (over the air interface) could be 0.1 – 1 ms.

8) Reliability

Reliability over the air interface relates to the capability of transmitting successfully a predefined amount of data within a predetermined time duration with a given probability.

The research target of reliability (over the air interface) could range from 1-10−5 to 1-10−7

At this stage it’s a bit tricky to do a comparison with 5G because we don’t yet know precisely what the 6G standard will end up adopting, but we recall that 5G set a minimum standard for peak data rates of 20Gbps (download) and 10Gbps (uplink) – this is of course shared capacity and not for individual user connections.

The old 5G target values for the end-user experienced data rates in a Dense Urban (eMBB) environment were also 100Mbps for the downlink and 50Mbps for the uplink. Likewise, 5G aimed to deliver an ideal latency time (measured in milliseconds, where smaller figures are faster) of 4ms in eMBB environments and down to just 1ms on fixed wireless (URLLC) connections.

Suffice to say that 6G is aiming a fair bit higher than all of these and the ITU has set out some examples of what this extra performance could mean. Now brace yourselves for the usual hype train, but remember that a lot of this stuff is just as possible under a modern and well-equipped 5G and even some 4G networks.

Expected usage scenarios for 6G include:

➤ Immersive communication to provide a rich and interactive video experience for users.

➤ Hyper-reliable and low-latency communication to enable the scale-up of intelligent industrial applications including telemedicine and management of energy and power grids.

➤ Enhanced ubiquitous connectivity, especially in rural, remote and sparsely populated areas with the aim of bridging the digital divide.

➤ Massive communication to include expanded use of Internet of Things (IoT) devices and applications in smart cities, intelligent transport systems and sectors such as health, agriculture, energy and environmental monitoring.

➤ Artificial intelligence (AI) and communications to support AI-powered applications.

➤ Integrated multi-dimensional sensing to improve assisted navigation, and high-precision positioning including object and presence detection, localization, imaging and mapping.

For the next phase of 6G’s development, companies and industry associations will submit proposals for the IMT-2030 Radio Interface Technology (RIT) for ITU-R consideration in early 2027. These submissions will then be evaluated against the agreed minimum requirements prepared by ITU’s expert group on IMT systems (ITU-R Working Party 5D), with the prospect of getting a final set of 6G technology standards approved by 2030.