Analyzing the Hurdles to Achieving a Wireless Virtual Reality
New study shows that wireless access to high-quality virtual realities is off-limits until signal transmission comes up to the mark
Daejeon, March 2020
Virtual reality (VR) systems are currently all wired. But if they could be made wireless, their potential applications would extend to many fields, including education and medicine. However, wireless VR systems require the use of high-frequency bands, which causes a variety of issues. Can existing technology overcome these issues? A research team from Korea recently answered this question.
We know virtual reality (VR) as technology that provides a fresh and immersive experience in entertainment and gaming. But what is lesser known is that VR can also have myriad novel applications across many fields, including medicine, education, and military domains. Researchers worldwide are working on broadening and enhancing the VR experience, and have achieved tactile sensations along with unprecedented video quality and framerate (16K at 90 fps). However, a notorious challenge still prevents VR systems from really taking off: they are not wireless. “Wires associated with VR devices can lead to several problems, including restriction of user movement, limitation of multiuser services, and scalability issues. Unfortunately, typical wireless systems such as Wi-Fi cannot support the required data transfer rates,” states Dr. Na.
For powerful VR applications, millimeter-wave (mmWave) bands are required, on which high-frequency signals of over 30 GHz can be transmitted, allowing for the necessary high speeds. However, the use of mmWave bands for VR is not straightforward and poses many problems. High frequencies require a clear line-of-sight between transmitter and receiver, and VR users tend to accidentally block the transmission path with their body. Moreover, the antennas in such systems irradiate a narrow beam, and aligning the server’s antenna with that of the mobile VR headset is crucial. To make things worse, multi-user VR environments face problems such as interference and server deafness, which further hinder transmissions.
In this study, scientists individually considered these problems and their potential solutions using existing technology. After determining the necessary data rate for high-quality VR services (roughly 1 Gbps), they conducted a series of experiments and simulations to gauge the feasibility of implementing a mmWave VR system using commercially available devices and the 802.11ad protocol, designed by the IEEE for mmWave communications.
First, the researchers performed individual experiments for each of these problems using a laptop and a VR dongle. Unfortunately, the performance degradation was very severe in all cases, limiting data rates to 0.7 Gbps or less even though the protocol theoretically allows for transmissions at 4.62 Gbps. “It is clear that such problems are yet to be addressed and must be solved using existing techniques that improve high-quality VR capabilities,” states Dr. Na. Then, simulations of a VR military training environment were carried out, mainly highlighting the challenges posed by inter-server interference. The results were promising and showed that beamforming using a thin beam can achieve the necessary speed even for a large number of users.
This study showcases some of the current practical barriers to the implementation of mmWave VR systems and how it may be possible to surpass them with existing technology. Future research will hopefully reveal more solutions, such as solutions to the deafness and blockage problems, so that we can immerse ourselves in unprecedented VR worlds and unlock novel applications.
Reference
Names of authors: Woongsoo Na1, Nhu-Ngoc Dao2, Joongheon Kim3, Eun-Seok Ryu4, and Sungrae Cho5
Affiliations:
1Department of Computer Science and Engineering, Kongju National University
2Institute of Computer Science, University of Bern
3School of Electrical Engineering, Rep. of Korea University
4Department of Computer Education, Sungkyunkwan University
5School of Software, Chung-Ang University
About Assistant Professor Woongsoo Na
Woongsoo Na received the B.S., M.S., and Ph.D. degrees in computer science and engineering from Chung-Ang University, Seoul, South Korea, in 2010, 2012, and 2017, respectively. He is currently an Assistant Professor with the Department of Computer Science and Engineering, Kongju National University, Chenan, South Korea. He was an Adjunct Professor with the School of Information Technology, Sungshin Women’s University, Seoul, from 2017 to 2018, and a Senior Researcher with Electronics and Telecommunications Research Institute, Daejeon, South Korea, from 2018 to 2019. His current research interests include mobile edge computing, flying ad hoc networks, wireless mobile networks, and explorations beyond 5G.
Media contact:
Email: wsna@kongju.ac.kr
