It took a long time for folks to get used to the idea of using millimeter wave (mmWave) frequencies for 5G wireless communications. Verizon, for one, spent a lot of money on mmWave, only to have some Wall Street analysts and others continue to second-guess its decisions.
Some good reasons support the skeptics, yet a lot of research and investment are going toward mmWave so that this mostly untapped spectrum will work in wireless operators’ favor. So if the next big frontier is even higher than mmWave, it might be time to hold onto your hats, because the ride is going to get a lot more wild, and some would say, downright crazy.
Wireless communications enabled by Terahertz (THz) in 6G is one of the topics to be explored during Fierce 5G Blitz Week, a free online event. On Wednesday (August 4), the event features keynotes from professors at academic institutions leading the charge, including Josep Jornet of Northeastern University, Qammer Abbasi of the University of Glasgow and Ranjan Singh of Singapore’s Nanyang Technological University.
Of course, 5G is still rolling out and the standards for 6G have yet to be fully conceived and written. However, the THz band is seeing a lot of attention from both industry and academia, Abbasi told Fierce via email. THz loosely refers to frequencies above 100 GHz.
Advanced multimedia services such as truly immersive extended reality (XR), mobile holograms and digital replicas, nano healthcare, three-dimensional (3D) calls, haptics communications, unmanned mobility, tele-operated driving and the nano-inspired internet of things are some examples of promising use cases of terahertz communications in 6G, according to Abbasi.
In fact, 6G needs to provide a much higher data rate than 5G, which was designed to achieve 20 Gpbs peak data rate. “In 6G, we are looking to provide the peak data rate of 1,000 Gbps,” he said.
Get ready for digital twins
With the help of advanced sensors, artificial intelligence (AI) and THz communication technologies, it will be possible to replicate physical entities, including people, devices, objects and places in a virtual world, Abbasi said.
“The digital replica of a physical entity is called a digital twin, and in a 6G environment, users will be able to use digital twins to explore and monitor the reality in a virtual world, without temporal or spatial constraints,” he said. “THz frequency imaging and spectroscopy will support real-time and perpetual data on the human body through non-intrusive, contact-free, and dynamic measurements,” such as digital health technology.
The idea of THz being applied to holograms and digital imaging isn’t all that surprising when one considers how higher frequencies are used in airport security imaging systems, for example. Higher frequencies result in better imaging, it appears.
There was a time, not that long ago, when no one wanted much to do with THz signals, and the sensing community was saying, “Well, maybe you don’t want them, but we love them for imaging,” such as in airport security systems to inspect the content of items without having to open those items – like luggage or boxes, said Jornet, associate professor at Northeastern University.
The idea of using THz for applications outside the sensing community has made inroads in recent years, especially in wireless communications. Asked about how far THz has come in recent years, Jornet noted that oftentimes, there are the people who work on theories and those who build devices, and they haven’t always been in the same room, so to speak. If you talk to the “theory” people, they think anything is possible. If you talk to the “product” people, they see where obstacles lie for real-world deployments.
Bringing together both sets of experts can lead to more productive discussions. “I think one of the healthy things that has been happening in the last 10 years is you’ve had more groups of inter-disciplinary people, so in the same project, you have people who can build radios and people who can think of how they would like those radio to be,” he said.
That’s encouraging when people are just starting to develop their “wish lists” for 6G and THz moves from the subject of academic papers to the agendas of federal regulators like the FCC and international spectrum bodies like the ITU.
There’s still room for the “crazy” ideas. “We keep looking at the crazier topics,” Jornet said, noting research into computers that are configured to control a human brain and vice versa. That may sound slightly crazy today, but 10 years from now, it’s quite possible that will no longer be the case.