In the article ‘6G, the Path to the Fusion of the Digital and Physical Worlds,’ we explained that it is time to start talking about 6G. We also previewed what the world will look like with the sixth generation of cellular networks: connected, sustainable, digitized, and programmable.
In this article, we will focus on three technologies that, until a few years ago, might have seemed like the product of a science-fiction writer or screenwriter’s imagination. Three technological advancements that will be made possible by 6G:
Immersive Holographic Telepresence with Extended Reality
Although holographic presence has been possible for more than a decade, the experience is not complete without that immersive capability with extended reality. The moment in the Star Wars saga when Princess Leia appears as a holographic projection from R2-D2 asking for help from Ben Kenobi and Luke Skywalker would be a much less sophisticated precursor to the advancement we are discussing. This future service will consist of virtually representing a person in a specific location while they are physically elsewhere. Moreover, it will allow the person to feel as if they are truly in the remote location. For example, it may appear as though they are in the office during a meeting while actually being at home, on the subway, or on the bus.
This technology’s most immediate application could be in the workplace (for instance, for remote meetings) and for social interaction. This represents a significant leap forward from virtual reality and extended reality. While both technologies provide an enhanced user experience of the environment, they do not have the telepresence capability.
What will be needed to make this technology possible?
To make these types of services possible, portable devices (wearables) such as smart glasses or contact lenses, and other items embedded in clothing, will be necessary. Bio-implants capable of gathering environmental and contextual information might also be required. For telepresence interaction to be more intuitive and efficient, current keyboard and mouse interfaces should be replaced by gestures, voice, or eye movements.
Regarding the technical challenges for commercializing this type of service, two significant hurdles exist. On the one hand, network transmission capacity will likely need to increase by two orders of magnitude compared to 5G, moving from speeds of tens of gigabytes per second to terabytes per second. Additionally, communication delays must be nearly zero and constant to ensure real-time telepresence without causing asynchrony. This issue would be particularly uncomfortable, for example, in a meeting with several participants.
Once these challenges are overcome, ensuring the security of 6G communication must be a priority. This is the focus of the 6GEnablers project. In this project, Gradiant is working on different security mechanisms. One area of work is a proof of concept for PKG (Physical-layer Key Generation), an innovative mechanism for generating secure keys based on communication channel information. Additionally, in 6GEnablers, Gradiant is also developing smart applications called xApps, which are used to detect, classify, and mitigate network security anomalies such as interference. These applications could be installed on an intelligent network controller called RIC by network operators, similar to how we download and install apps on a mobile phone.
Situational Awareness
Understanding the environment is essential for effective wireless communication. Situational awareness, also known as environmental awareness, aims to provide as much information as possible about the surroundings of the communication equipment (typically the transmitter and receiver).
The basic purpose of situational awareness is to efficiently address potential unwanted interactions with the environment. Factors that can affect communications include obstacles that might block or reflect signals (from buildings to humans), interference, and the behavior of the radio communication channel. However, this approach is more typical of 5G systems. Situational awareness with 6G would be able to achieve a much more complete characterization of the environment. For example, it would include sensory perceptions that enable services like advanced localization systems or immersive telepresence. These functionalities require network capabilities that 5G lacks, as well as 3D communication channel models across a wide frequency range, reaching up to terahertz (THz).
Another challenge to making this advance possible is the development of advanced sensing systems capable of rendering the environment in real-time and providing not only images and audio but also object positioning. These sensing systems are expected to be based on THz technologies and the integration of sensing and communication (ICAS). Their development is currently in the early stages.
3D High-Precision Positioning, Localization, and Tracking
Adapting to our living environment requires high precision. Actions such as turning a doorknob, picking a specific book off a shelf, or choosing the right tool require millimeter accuracy. 3D high-precision localization and enhanced tracking capabilities at the centimeter level or less, especially indoors, will open many new opportunities. The factories of the future, warehouses, hospitals, and smart libraries could achieve full automation. Future robots equipped with this 3D high-precision positioning, localization, and tracking technology could match a person’s capacity for specific tasks.
What will future libraries look like?
If this technology is integrated into these spaces, books could be identified with very small wireless modules, eliminating the need for classification: their positions would be automatically collected in a database or even a 3D digital twin. A robotic librarian could locate a book for a user using that positioning information.
This type of high-precision localization is also eagerly awaited by autonomous systems (drones, vehicles), especially in smart factory environments where two or more robots operate collaboratively. Additionally, a drone may need to land on a moving transport vehicle to recharge, or a delivery robot may need to fill a smart container (tank/container) with a specific liquid or solid substance. In such close-range use cases, centimeter-level relative localization accuracy is required to complete the task.
Current positioning systems do not provide these levels of accuracy. Additionally, full integration of positioning mechanisms with the 6G network is necessary, which does not happen in 5G. To achieve this, THz technologies must be developed, and ultra-narrow beams (pencil-thin) must be achieved for very high pointing precision, along with the development of the sensing and communication integration technology mentioned earlier.
Work on 6G Specifications and Designs Is Underway
These are some of the technologies that 6G development could enable. As Joaquín Escudero explained in his article, it is likely that this sixth generation will not be available until the early 2030s. In the meantime, work has begun on the specifications and design of 6G through projects developing the necessary technologies to provide the services and applications mentioned above, such as the 6GOPENVERSO-NET project in which Gradiant is developing a sub-THz band link prototype with sensing capabilities.
Funded by the Ministry for Digital Transformation and Public Administration and the European Union-NextGenerationEU under Spain’s Recovery, Transformation, and Resilience Plan.
