# A 5G-Based VR Application for Efficient Port Management
## 3 Application of 5G + VR in Smart Ports
### Key Process  
The 5G + VR smart port framework proposed in this paper has two VR modes as shown in Figure 3, where different modes can be selected depending on the network QoS and application requirement. In Mode 1, the virtual reality is reconstructed by building every real-world model in the virtual scene, in which real-world related parameters such as movement speed, angle, and collision are rendered through Unity3D. Mode 1 is suitable for limited networks with low bandwidth, as only the interaction commands are needed to be transmitted between the real world and the virtual scene. Its latency is typically more than 15 ms in a 4G network environment and can be reduced to less than 5 ms in a 5G network environment while having a 0% packet loss rate. In Mode 2, as shown in Figure 4, the immersive VR experience is achieved by real-time video captured by the 360\({}^{\circ}\) camera and transmitted through the 5G network. The terminal operators can observe the real-time 360\({}^{\circ}\) video of the captured scene by wearing a VR device or using a PC monitor. In this way, the VR experience is degraded from the original 6 Degrees of Freedom (DoF) to 3 DoF, where the viewers are limited to a 360\({}^{\circ}\) view at a fixed point in the remote scene without the feasibility to move around. This is due to the extremely high data volume (about 10 times that of 3 DoF) and video rendering computation capability limitations in implementing 6 DoF VR video streaming. According to the QoE evaluation mode, results show that the video resolution in the VR environment must reach at least a 4K resolution level for the viewers to avoid feeling fatigued when using for a long  
Figure 3: VR mode selection. period (e.g., 15-20 min). This mode requires a high transmission rate (e.g., above 20 Mbps), and the latency is generally 20 ms under the 5G network, which is fully supportable for normal work in most departments of smart ports. For some specific scenarios, for example, assisted driving, higher safety can be achieved by having an ultra-low delay in 5G slicing networks. This requires higher-speed networks or edge deployment of 5G with theoretical latency of 5 ms or even less than 1 ms. The main process of Mode 2 consists of three stages: video capture, transmission processing, and video playback. (1) Video capture: Panoramic cameras are used to shoot panoramic images, connecting to the base station through a 5G CPE (Customer Premise Equipment), 5G mobile phone, or the 5G module that is equipped with a camera, and they are responsible for uploading the generated RTSP or RTMP format video stream through the 5G access network. (2) Transmission processing: The 5G bearer network guarantees the port video content through the \"virtual private network\" to ensure that the 360\({}^{\circ}\) video stream is smoothly transferred to the content platform located in the cloud. After the content platform performs a series of operations such as local storage, resolution conversion, coding rate conversion, and encapsulation format conversion on the live 360\({}^{\circ}\) stream, it will generate a new 360\({}^{\circ}\) video stream and transmit it to the terminal through the bearer network. In a traditional network such as WLAN and 4G, the video streaming quality is easily affected by network fluctuations and its QoE cannot be guaranteed for remote  
Figure 4: Mode 2 key process of smart port. control. Industrial 5G networks can provide a slicing network that preserves sufficient network resources for steady 360\({}^{\circ}\) video streaming with a high QoE level. 3. Video playback: 360\({}^{\circ}\) video streams are transmitted to TVs, mobile phones, VR helmets, and other terminal devices through the 5G base station downlink channel for further decoding and playback. The requirements for video stream bit rate, resolution, and other parameters obtained by different terminal devices vary according to their computation capability, network connection, screen size, application scenario, etc.