The development of next-generation communication systems promises to enable extended reality (XR) applications, such as XR gaming with ultra-realistic content and human-grade sensory feedback. These demanding applications impose stringent performance requirements on the underlying wireless communication infrastructure. To meet the expected Quality of Experience (QoE) for XR applications, high-capacity connections are necessary, which can be achieved by using millimeter-wave (mmWave) frequency bands and employing highly directional beams. However, these narrow beams are susceptible to even minor misalignments caused by small-scale user mobility, such as changes in the orientation of the XR head-mounted device (HMD) or minor shifts in user body position. This article explores the impact of small-scale user mobility on mmWave connectivity for XR and reviews approaches to resolve the challenges arising due to small-scale mobility. To deepen our understanding of small-scale mobility during XR usage, we prepared a dataset of user mobility during XR gaming. We use this dataset to study the effects of user mobility on highly directional communication, identifying specific aspects of user mobility that significantly affect the performance of narrow-beam wireless communication systems. Our results confirm the substantial influence of small-scale mobility on beam misalignment, highlighting the need for enhanced mechanisms to effectively manage the consequences of small-scale mobility.

翻译：下一代通信系统的发展有望实现扩展现实（XR）应用，例如具有超逼真内容和人类级感官反馈的XR游戏。这些高要求应用对底层无线通信基础设施提出了严格的性能要求。为满足XR应用预期的体验质量（QoE），需要高容量连接，这可通过使用毫米波（mmWave）频段并采用高定向性波束来实现。然而，这些窄波束极易受到由小尺度用户移动性（如XR头戴式设备（HMD）的方向变化或用户身体位置的微小偏移）引起的轻微失准影响。本文探讨了小尺度用户移动性对XR毫米波连接的影响，并综述了解决由小尺度移动性所引发挑战的方法。为深入理解XR使用过程中的小尺度移动性，我们构建了一个XR游戏期间用户移动性的数据集。利用该数据集，我们研究了用户移动性对高定向性通信的影响，识别了显著影响窄波束无线通信系统性能的用户移动性的具体方面。我们的结果证实了小尺度移动性对波束失准的显著影响，强调了需要增强机制以有效管理小尺度移动性带来的后果。