Section: 7.6.1 AR/VR
Content: Audio-visual interaction is characterised by a human being interacting with the environment or people, or controlling a UE, and relying on audio-visual feedback. In the use cases like VR and interactive conversation the latency requirements include the latencies at the application layer (e.g. codecs), which could be specified outside of 3GPP. To support VR environments with low motion-to-photon capabilities, the 5G system shall support: - motion-to-photon latency in the range of 7 ms to 15ms while maintaining the required resolution of up to 8k giving user data rate of up to [1Gbit/s] and - motion-to-sound delay of [< 20 ms]. NOTE: The motion-to-photon latency is defined as the latency between the physical movement of a user's head and the updated picture in the VR headset. The motion-to-sound latency is the latency between the physical movement of a user's head and updated sound waves from a head mounted speaker reaching their ears. To support interactive task completion during voice conversation, the 5G system shall support low-delay speech coding for interactive conversational services (100 ms, one-way mouth-to-ear). Due to the separate handling of the audio and video component, the 5G system will have to cater for the VR audio-video synchronisation in order to avoid having a negative impact on the user experience (i.e. viewers detecting lack of synchronization). To support VR environments the 5G system shall support audio-video synchronisation thresholds: - in the range of [125 ms to 5 ms] for audio delayed and - in the range of [45 ms to 5 ms] for audio advanced. The 5G system shall support service continuity for AR/VR to support immersive user experience under high UE mobility. When it comes to implementation of applications containing AR/VR components, the requirements on the 5G network could depend on architectural choices implementing these services. Note 3 in table 7.1-1 above gives an example on such dependences for a VR application in a 5G system. Table 7.6.1-1 below illustrates additional use cases and provides more corresponding requirements on the 5G system. - Cloud/Edge/Split Rendering – Cloud/Edge/Split Rendering is characterised by the transition and exchange of the rendering data between the rendering server and device. - Gaming or Training Data Exchanging – This use case is characterised by the exchange of the gaming or training service data between two 5G connected AR/VR devices. - Consume VR content via tethered VR headset – This use case involves a tethered VR headset receiving VR content via a connected UE; this approach alleviates some of the computation complexity required at the VR headset, by allowing some or all decoding functionality to run locally at the connected UE. The requirements in the table below refer to the direct wireless link between the tethered VR headset and the corresponding connected UE. Table 7.6.1-1 KPI Table for additional high data rate and low latency service