5G reality check – restrictions and the requirement for 6G
With 5G deployments still in the nascent era, it may appear too soon to be talking about 6G. But provided that the initial development of 5G started in 2010, now is the time for the telecoms industry to begin shifting its focus to the next G.
“But wasn’t G supposed to be the last G?” 5G was developed to be the first truly software-defined wireless standard, where network functions would be instantaneously spun-up, and new frequency bands could be swiftly programmed into future ‘revisions’ of 5G networks. 5G was supposed to see real time sensing networks facilitate autonomous vehicles, smart cities, VR and AR galore. However, the early deployments of 5G are starting to demonstrate some cracks, that could get us to a breaking point.
However, 6G isn’t here to re-write the script. A lot like 4G was an improvement to 3G, 6G will operate as an improvement to 5G, and will complete the work that 5G intended to do.
Getting to 5G’s breaking point
Every generation of wireless technology enhances upon the capacities of its predecessor. We’ve observed new generations that have needed a complete network overhaul, like the upgrade from 2G to 3G and from 4G to 5G, along with wireless generations that have enhanced and improved upon current infrastructure, such as 3G to 4G, and in due time, 5G to 6G.
5G’s hype has called out applications such as immersive video calling to vehicle-to-vehicle communications, through to remote surgery and precision remote control robotics. These use cases will need improved mobile broadband (eMBB) plus massive machine type communications (mMTC) plus ultra-low latency communications (URLCC) services.
Having to deploy dual or more network slices is fine for a restricted array of deployments, however network slicing en-masse is probably not a very elegant approach. And this is where 6G steps in. While 5G new radio evolution function like NR-Lite are exploring mixing URLLC and mMTC, and evolution is needed, furnishing a flexible system that can be compatible with hybrid services in a more organic fashion.
5G also reaches breaking point when we observe the data rate challenges of video and immersive applications like consumer holographic communications, telepresence and mixed reality (MR), in addition to multi-sensory extended reality (XR).
While present 360-degree 4K video needs data rates of 10-50Mbps, next generation 360-degree 8K demands data rates of 50-200Mbps, far more than what 5G can provide today. If we then think about XR and full immersive experiences, which need 200Mbps to 5Gbps – then it’s not very long before 5G gets to its breaking point. And XR isn’t even the most demanding use case. Holography is the application usually specified when we think of futuristic video and immersive experiences, but holographic needs almost Terabi/second data rates.
6G’s technology advancements
To reach these Gbps capabilities, then breaking into higher spectrum bands is minimally needed. As a matter of fact, 3GPP has already explored 72 Ghz spectrum bands to be compatible with preliminary XR applications. However, pushing into these spectrum bands isn’t bereft of challenges. When pushing into 80Ghz or 100Ghz, issues with digital design of OFDM (Orthogonal Frequency Division Multiplexing) strategies appear. This implies going from 5G to 6G is probably to need a genuinely new radio design.
Intelligent metasurfaces will also be a critical prospective technology within 6G, as they will be able to furnish a turbo boost to line speed and data rates. This consists of implantation of smart antennas in the radio channel that manipulate Snell’s law, and eventually, they have the outcome in introducing a new RAN element into the network that wasn’t there prior.
Why now?
After all the promise and hype that has been created by 5G, cracks are starting to appear, and the very hyped use cases we have heard about time and time again will not be viable with current 5G technology.
The telecoms domain usually develops tech 10 to 15 years in advance, which implies now is the time to look at developing 6G to find a solution to 5G’s shortfalls. 6G’s development is not necessarily a quick fix, and like every other generation of wireless technology. It will be several years in the making.
The relationship amongst 5G and 6G is symbiotic – 6G cannot exist without 5G, and the same is true the other way around. 5G has laid the very critical groundwork for the next gen of wireless, and it will be 6G’s job to carry it over the line.