MAC Scheduling for Multiuser Wireless Virtual Reality in 5G MIMO-OFDM Systems

Wireless Virtual Reality (VR) is a new-arising technology to enable the untethered connection between VR server and VR client, which needs to support simultaneously ultra-high data rate and ultra-high transfer reliability for video streaming, and also ultra-high responsive speed for motion-to-photon latency. Such three ultra-high (3UH) requirements constitute the basic characteristics of the generalized tactile internet. This paper proposes a multiuser MAC scheduling scheme for VR service in 5G MIMO-OFDM system, which can maximize the number of simultaneous VR clients while guaranteeing their 3UH quality-of-experience (QoE). Specifically, this scheme is composed of three novel functions, including video frame differentiation and delay-based weight calculation, spatial-frequency user selection based on maximum aggregate delay-capacity utility (ADCU), and link adaptation with dynamic block-error-rate (BLER) target. In addition, a low-complexity downlink MIMO user selection algorithm is developed, which can reduce the calculation amount with one order. It is demonstrated by the simulation results that the proposed scheme increases 31.6% for the maximum number of simultaneously served VR users than the traditional scheme with maximum-sum-capacity based scheduling and fixed BLER target based link adaptation.