Extended Reality (XR) is a general term for virtual reality (VR), augmented reality (AR) and mixed reality (MR). Cloud-based XR technology will significantly reduce the computing load and energy consumption of XR terminal devices, get rid of the shackles of cables, and XR terminal devices will become lighter, more immersive, more intelligent, and more conducive to commercialization.

For 2030 and beyond, the improvement of network and XR terminal capabilities will push XR technology into the era of full immersion. The cloud XR system will be combined with the new generation of network, cloud computing, big data, artificial intelligence and other technologies, enabling business and creative, industrial production, culture and entertainment, education and training, medical and health care and other fields, to facilitate the digital transformation of all industries.

In the future, cloud XR system will realize voice interaction, gesture interaction, head interaction, eye interaction and other complex services between users and the environment. It needs to meet ultra-low delay and ultra-high bandwidth in a relatively determined system environment to bring users extreme experience. Existing cloud VR systems require no more than 20ms MTP delay, while the existing end-to-end delay is up to 70ms. For 2030 and the future, the total delay based on cloud XR will be at least less than 10ms. According to the calculation of the Virtual reality industry promotion Committee, in order for virtual reality user experience to reach the level of full immersion, the angular resolution should reach 60 PPD, the frame rate should be no less than 120 Hz, the field Angle of view should be no less than 130°, and 12 bits per pixel should be able to eliminate the vertigo caused by demodulation conflicts to a certain extent. Calculated according to the compression ratio of 100, Throughput requirements are about 3.8 Gbps. Typically, XR technology leverages mobile computing through powerful machines and creates experiences that we access through wearable devices like goggles or eyeglasses. However, in the future, XR technology may also include us being able to walk in and experience an XR room. XR will produce a number of killer applications for 6G in the AR/MR/VR range. Unable to provide extremely low latency for data-rate-intensive XR applications, upcoming 5G systems are still unable to provide a full immersive XR experience that captures all sensory inputs. A truly immersive AR/MR/VR experience requires a joint design that integrates not only engineering (wireless, computing, storage) requirements, but also perceptual requirements derived from human senses, cognition, and physiology. Minimum and maximum perception requirements and limitations must be taken into account in the engineering process (calculation, processing, etc.). To this end, a new concept of quality of physical experience (QoPE) entails measuring the merging of physical factors from human users themselves with classical QoS (e.g., delay and rate) and QoE (e.g., average opinion score) inputs. Some factors that influence QoPE include brain cognition, body physiology, and gestures.

Virtual reality and augmented reality are two types of XR, but others exist as well. To review:

Augmented reality is the process of using computer-generated features or feelings to enhance real world objects. One example is the face filter on Instagram. Virtual reality is a full-sensory simulation of the real world. It usually uses headphones, gloves, or other props to make the user feel like he or she is immersed in a simulated world. Mixed reality is a combination of virtual and augmented reality in which physical and digital objects coexist. The hologram of a man in the conference room is mixed reality. Immersive reality is a term we sometimes hear referring to VR or MR. It simply means creating a seamless XR reality that is indistinguishable from the user.

1. Current and future XR features

Extended reality has become very popular and widely used, even if we don't realize it. Many apps appear in entertainment, such as Instagram filters or the Pokemon GO phenomenon. Still, others have found many applications in a variety of industries, including retail, marketing, real estate, health care, military, education, engineering, and more. The popularity of the technology means it is likely to continue to be a part of our lives. However, it is currently limited by our wireless technology. In particular, extended reality has the following problems:

High implementation costs: Most forms of XR require infrastructure that does not always exist. High resource consumption: To create a seamless virtual experience, computers need to access large amounts of data and computing resources. Network vulnerabilities: A growing body of research suggests that the XR is particularly vulnerable to data hacking. These shortcomings must be addressed in order to create a truly sustainable and practical set of extended reality technologies. The development of 6G can solve the above problems. Among the many topics discussed at 6G, how the nature of technology itself will change is the neat sounding concept of "physical convergence of information." The term, which first appeared in NTT Docomo's white paper, refers to the transfer and processing of data between cyberspace and physical space with zero delay. Further subdivided, it is through the use of wearable devices to transmit thoughts and actions in real time. This may seem far-fetched, but similar technology already exists. A mind-switching device, or brain-computer interface, is a technology that allows severely paralyzed patients to manipulate information on a screen. Although still under research, it shows that "physical fusion of information" is possible. Some researchers think 6G could eventually enable scientists to take advantage of brain-computer interfaces.

2. Other possibilities of XR in 6G

5G will significantly enhance extended reality, but we may not see anything truly extraordinary until 6G. Of particular interest, however, is the role of intelligent networks that host extended real-world resources. Taken together, these technologies can lead to very powerful XR applications. Some of these may include:

Multi-sensory experience: Research shows that unmatched data access and the ability to draw inferences from it with zero latency will eventually lead to a truly immersive XR experience. Some global brands use it for entertainment, while others use it for education. Telemedicine: The practice of remote patient care is called telemedicine, and 6G May make XR easier to do. Not only will patients without access to doctors have access to healthcare resources, but XR will make patient screening easier. Implants: Implants that allow users to communicate telepathically have been around in science fiction for a long time, but 6G could make them a reality. This will mean accessing the network whenever and wherever you want it.

3. Expand your thoughts about reality with 6G

Due to the limitations of current wireless technology, extended reality (XR) has a lot of untapped potential. That's a big reason why proponents are so excited about 5G and beyond. While many believe 5G will eventually make the XR sustainable, we suspect it needs 6GB to fully leverage its capabilities.

Still, extended reality will continue to gain ground in power and complexity as new technologies emerge. It is mentioned in many newly published papers on the properties and characteristics of 6G, suggesting that 6G will play a central role in our world in the 2030s and beyond.

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