What is 6G and future wireless?

Fundamentals

Even though 5G is still being rolled out to replace the aging 4G standard, its successor 6G is already in development. Like its predecessors, 6G networks are expected to be faster and handle increased bandwidth with lower latencies.

 6G networks are expected to provide more diverse capabilities than their predecessors and are more than likely to support applications beyond current mobile applications, such as virtual and augmented reality (VR/AR), AI and the Internet of Things (IoT). It's also speculated that mobile network operators will adopt flexible, decentralized models for 6G, with local spectrum licensing, spectrum sharing, and infrastructure sharing. All will be handled by intelligent automated management underpinned by mobile edge computing, short-packet communication and blockchain technologies.

New wireless communication standards are developed about every ten years, and 6G is expected to come into play around 2030. As it stands, nothing is set in stone in regards to 6G, and even its designation could be replaced by something else. With that in mind, there are some theoretical aspects of 6G and what it might have to offer when it eventually deploys. With the rollout of 5G, consumers will continue to use more mobile devices and consume internet data at ever-increasing rates.

While telecoms are still relying on 4G for consumer use, 5G is on course to replace the aging tech, albeit very slowly, with most deployed in densely packed cities. The 4G/LTE standard, introduced in 2009, was a game-changer for mobile devices as it boosted data speeds and allowed users to stream HD movies, play games and transfer large amounts of data at approximately 33 Mbps.

5G moves beyond 4G's capabilities by utilizing microwave and mmWave technology to increase its speed to around 900 Mbps or higher. Those higher speeds and bandwidth are comparable to commercial broadband providers, allowing for increased applications that move beyond media streaming. The IoT and connected devices will have real-time sensing capabilities. Edge computing can take advantage of the cloud and gain access to data instantly. Healthcare providers could gain instant knowledge from patients wearing medical devices. 5G offers applications in retail, industry, agriculture and manufacturing. The list is nearly endless, but we won't see 5G's true potential for some time yet until the new technology is deployed worldwide.

 

Notable differences between each standard, including speeds and applications. (Credit Cabe Atwell) 

6G Technologies

As mentioned, 6G is too early in the development stage to have factual information on its technologies or its capabilities. It's suspected that most telecoms will adopt flexible, decentralized business models with local spectrum licensing/sharing and infrastructure sharing similar to 5G. According to a 2019 paper from Virginia Tech, engineers describe 6G as a fully integrated, internet-based system that provides instant communication between users, devices, vehicles, and the surrounding environment. Imagine going beyond the Internet of Things to the Internet of Everything, which is what 6G could theoretically provide.

Some experts believe 6G could reach speeds of up to 1 Tbps, a thousand times faster than the 1 Gbps that current fiber optic packages can supply. The Federal Communications Commission (FCC) opened up the prospect of 6G speeds in 2019, allowing companies to experiment with terahertz waves (AKA submillimeter waves), which fall into the 95 GHz to 3 THz spectrum. In comparison, 5G utilizes low-band, mid-band or high-band millimeter-wave (mmWave) and microwave technologies to achieve a 24 GHz to 40 frequency range. While terahertz waves could boost 6G speeds into the 1 Tbps range, it would suffer the same limitations as 5G in that it has a limited range and requires "line-of-sight" between the transmitter and end-user.

Engineers at the University of California Santa Barbara have designed a device that can help speed up the 6G development process using N-Polar gallium nitride high-electron-mobility transistors (HEMTs). Those HEMTs incorporate a junction between two materials with different bandgaps that function as a channel instead of a doped region commonly found in MOSFETS. As a result, the HEMTs allows the device to operate at much higher frequencies (140 THz to 230 THz), like those required by 6G.

Last year, researchers from the Nanyang Technological University of Singapore and Osaka University of Japan designed a chip for terahertz waves, which could be utilized for 6G. Earlier this year, engineers from Millimeter Wave Products  developed amplifiers for G-bands operating in the terahertz waves. These are a few of the tools that could help 6G come to fruition and move beyond the research stage. Considering the slow advance of the 5G rollout, it could be a decade or more before 6G becomes a reality.

(Credit Nvidia via Flickr)

Potential Applications for 6G

It isn't easy to know what 6G will be capable of at this stage, but if it's anything like previous standards deployment, the impact could be huge. Autonomous vehicles, drones, smart factories, and AI have gained a lot of traction during the rise of 5G. Some experts feel 6G could advance those applications even further, even tasking AI to keep it all coordinated and running smoothly. Self-driving cars might utilize collaborative AI to talk with others for navigation, pedestrian/object avoidance and traffic updates. AI and edge computing could also make devices, such as traffic and street lights, act as networking antennas in surrounding areas, allowing vehicles and people to maintain a Wi-Fi connection.

VR and AR could become more immersive. Imagine cellular surfaces and objects that feel tangible via connected implants or even wireless human/computer interfaces. A Virginia Tech 2019 white paper describes that smartphones will eventually be dumped in favor of wearables, headsets/glasses, and implants for multisensory extended reality (XR). Others envision the complete merging of cyberspace and physical reality. Imagine thinking about any given subject, then having access to data stored within the cloud for more information --  the ultimate cheat tool for students.

Of course, these potential applications are speculative as research for 6G is still in its infancy, and 5G is still several years away from being fully deployed. The internet may even need to be reengineered before it can support 6G. All those devices will require constant power in some cases, relying on batteries and stable connections to the electrical grid. All that manufacturing and energy usage could also be a detriment to the ecosystem unless they could be tied to a sustainable power source. That said, 6G certainly brings more to the table than its predecessors, at least on a speculative paper, but it will be an exciting prospect if any of those applications come to fruition.