Testing eXtended Reality (XR)

XR technologies constitute a fundamental part of the metaverse as they provide interfaces to experience vast virtual worlds. The performance of XR-based technologies and services will be critical to delivering high quality metaverse experiences.
A compatible testbed setup is needed to learn more about the connectivity and performance of XR applications and devices and to assist in the validation of designs. This requirement stems from the necessity to thoroughly test the performance of XR-based applications over today’s 5G and Wi-Fi and future 6G networks. Such a testbed would encompass the entire journey of data from server to client, navigating through the intricacies of cloud computing architectures and ultimately reaching the end-user devices such as 5G smartphones tethered to AR glasses or VR headsets. The testbed allows the testing of an application across a variety of devices and their combinations, ensuring interoperability and optimal performance in real-world scenarios. This comprehensive testing environment enables content developers as well as design and test engineers to identify and address potential bottlenecks or performance issues, ensuring that XR applications deliver a high-quality, immersive experience to users across different platforms and network conditions.

Push 5G technology with XR applications

The rollout of 5G is still in its early stages and has not met the initial promises so far. Many consumers are yet to experience the benefits of this technology – the average revenue per user (ARPU) has not shown a significant increase compared to 4G LTE, making it difficult to invest further in the 5G technology (e.g. expand mmW frequencies where additional capacity is needed). Hence, the technology has reached a pivotal point. According to experts, 5G requires a push from a “killer app”. XR and the metaverse are considered a possible “killer app” and a critical driver in unlocking the full potential of the 5G technology.

The 3rd Generation Partnership Project (3GPP) thoroughly reviewed applications of extended reality (XR) in its Release 17. This review was crucial for pinpointing existing limitations and possible improvements in the current 5G standard to further finetune the 5G networks and 5G devices for seamless operation of XR-based applications. It set the stage for the next phase of 5G, known as 5G-Advanced, which is covered in Release 18. This release defined specific features and enhancements of functions with the explicit aim of optimizing 5G for XR. A crucial part of this process was a comprehensive analysis of various use cases that illustrated the practical application of 5G in enabling XR experiences. Among these, the scenario of 5G-enabled AR-animated avatar calls stood out as a particularly illustrative example. This use case not only highlights the innovative integration of 5G with XR but also serves as a valuable entry point for exploring the technological hurdles associated with testing XR functionalities over 5G networks.

Design and test challenges for the Metaverse and XR

XR technologies offer immersive interfaces to experience vast virtual worlds and can therefore be seen as fundamental to the metaverse. Providing a functional ecosystem of XR-capable applications and devices like AR glasses and VR headsets, chipsets to power mobile devices and network infrastructure components are therefore crucial to accessing and engaging with the metaverse in all its forms and variants.

High data rates and low latency are determining factors for XR services as they are vital to avoid issues like motion sickness and to create a smooth immersive experience.

While specific details among others depend on the device form factor, the targeted use case and its computing capability, XR devices for consumer applications generally need to be small, lightweight and even fashionable, but also need to have a low power consumption. Such requirements pose the challenge of reducing size and power consumption without compromising performance and capabilities.

It is for this reason that efficient energy use is particularly important in XR devices. This ensures longer usage times as well as sustainability – particularly in portable and wearable devices, which are integral to the metaverse experience.

The seamless interplay of all these different components, provided by different vendors, requires thorough testing to ensure they operate at the required level.

When testing XR devices, critical factors such as functionality, usability, performance, and user comfort are evaluated. The unique and advanced features of XR applications and devices mean that traditional testing tools and protocols may not be adequate. This adds a layer of complexity to XR testing, requiring specialized approaches to effectively assess these devices.

Testing solutions for the Metaverse and XR

As a leader in test and measurement solutions, Rohde & Schwarz provides a cutting-edge testbed setup that allows the testing of a seamless operation of XR-based applications on mobile devices and chipsets. QoE and performance of AR and VR devices and applications as well as chipsets to be tested.

At the core of this setup are our R&S®CMX500 5G one-box signaling tester combined with our R&S®ATS1800C chamber, that emulates either a 5G NR or Wi-Fi network to test XR applications tested from an end-to-end perspective.

We provide a controlled environment for testing AR glasses or VR headsets, tethered to 5G devices via Wi-Fi to measure parameters like throughput and latency under various network conditions by emulating different traffic models and traffic patterns. The setup allows the extensive testing of mobility scenarios (e.g. handovers), where typically peaks in network impairments (e.g. IP jitter) are experienced. Due to the parallel support of 5G and Wi-Fi, comprehensive interoperability and performance tests can be performed to check the offloading capabilities from the cellular to non-cellular networks and vice versa. It is essential to verify that the transition does not affect an application’s performance. Our solution can test different parameters and emulate the streaming of 3D content to users.

You can also benefit from our setup by mimicking congested networks or challenging radio frequency (RF) conditions and testing the performance of applications under such parameters. A robust and reliable user experience even under less ideal circumstances can thus be verified.