As 5G deployments continue, the industry and the R&D community are now laying the foundations for the development of 6G. In fact, the International Telecommunication Union (ITU) has released the timeline for the development of IMT-2030 (as 6G is known at present). The process of finalising its predecessor, IMT-2020 (or 5G), took approximately seven years. The IMT-2030 timeline is stretched over ten years.
In short, ITU is currently forming a 6G vision – and the industry and the research community are carrying out technology research to develop requirements and concepts.
National and international cooperation will be important during this initial phase to ensure the technology goals are ambitious but realistic. I believe it is essential that the industry, R&D community and regulators collaborate to achieve these goals.
Spectrum, of course, is going to play a significant role in this process. Understanding spectrum needs and availability can help identify new spectrum bands suitable for mobile communication systems.
Spectrum can be made available in three different ways:
- Re-farming existing spectrum: New technologies can provide higher spectrum efficiency. However, re-farming will depend on clearance plans and the use of legacy technologies. In particular, there may be some challenges in re-farming 2G and 3G due to current requirements for providing eCall (an EU-pioneered emergency call solution) in Europe using 2G and 3G.
- Sharing spectrum: Due to the lack of unoccupied spectrum bands, spectrum sharing is gaining more attention in recent years, not least because technological advances have made spectrum-sharing more feasible.
- Utilising new spectrum bands: 5G enabled the use of mmWave bands. 6G may go beyond this. There are two main areas of radio spectrum under consideration for new spectrum bands for IMT 2030: 7-24 GHz and THz. Bands at about 92 GHz (commonly known as ‘THz bands’) have attracted interest in recent years and may have a role in future communications systems. However, the technology deployed needs to mature to make these spectrum bands viable in commercial networks.
I have explored the available opportunities for mobile services in the 7-24 GHz range. I have noted that, firstly, all available spectrum is already allocated to a number of different services in the 7-24 GHz range. Hence, clearing or sharing is necessary before regulators can make this spectrum available.
As readers will know, spectrum allocation-related decisions are debated and decided at World Radio Conferences (WRCs). Although individual countries can make their own decisions related to spectrum use, administrations prefer a harmonised approach unless there are specific reasons to do otherwise. Put simply, a harmonised approach means equipment and device manufacturers will all work with the same part of the radio spectrum. In turn, the economies of scale will lower infrastructure costs, leading to more affordable consumer services. There’s also a regulatory boost: bands already allocated to ‘mobile’ service are likely to have a faster route to market.
I have explored all spectrum bands in the 7-24 GHz range from the ITU Frequency Allocation Table to see what the potential opportunities could be. The figure below highlights the spectrum bands with primary mobile allocations in the 7-24 GHz frequency range. The bar height shows how many other services the mobile service may have to share with. The width of the band shows the bandwidth (drawn to scale). None of the bands is allocated to mobile service alone. However, 65% of the spectrum is allocated to mobile service on a primary basis. In addition, none of the bands has IMT identification. In most cases, IMT deployments – that is 3G, 4G and 5G mobile systems – take place in the mobile bands with IMT identification. Interestingly, all mobile primary allocations in this range also have fixed primary allocations. There are about 50 different co-channel primary allocation combinations.
Sharing is likely to be essential for most spectrum bands available in the future. Of course, the cost and complexity of this approach will vary significantly from service to service; sharing is easier with some services than others.
Also, the regulatory measures required to enable sharing will be different in each case. In addition, the restrictions applied in these regulatory measures could vary from country to country and even from service to service. So, the devil is in the details. And, those details make the case or break it.
As for Real Wireless, we have conducted detailed sharing and co-existence studies for various global and national service providers, considering the most realistic parameters, and practical deployment scenarios to help them initiate the dialogue with regulators.
However, the most important consideration is that we can offer deep experience in technology and regulations. This will help service providers to make better, evidence-based decisions during engagements with the regulators.