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C-V2X and 5G for Vehicular Connectivity

We have made couple of introductory tutorials on "Connected and Autonomous Vehicles (CAVs)" and another one on "Introduction to Vehicle to Everything (V2X) and Cellular V2X (C-V2X)". These provide you with the basics needed to understand the technology. In addition, we have also collected "3GPP Technical Specifications (TS) and Reports (TR) related to V2X" here.

5G Americas has recently published a white paper titled, “Vehicular Connectivity: C-V2X and 5G,” which covers the impacts of 5G-based cellular vehicle-to-everything (C-V2X) technologies on vehicles, embedded infrastructure, and intelligent transportation networks. You can download the PDF here and this page contains a presentation and a summary video.

The paper also details how Multi-access Edge Computing (MEC), previously known as mobile edge computing, can help bring processing power near the vehicle to meet ultra-low-latency requirements, and to reduce network traffic towards a centralized datacenter. The paper states:

MEC is a type of cloud-computing located near the edge of the network. It helps to offer various end-to-end services based on the bandwidth and/or latency requirements needed for various applications. The roadside edge network infrastructure can provide vehicular services (over PC5) by aggregating various road-side sensors and data processing via an Edge Computing platform. This can adapt the CPU and storage resources to handle the large volumes of data to and from the vehicles or RSUs based on the service requirements. Furthermore, the MEC deployment can use a hierarchical architecture using gateways and roadside units to further reduce the latency and processing load of the overall network.

Operators or MEC providers can open the edge cloud and services to authorized third parties that will enable rapid development and adaptation of applications and services for vehicular services, mobile subscribes and other vertical market segments. MEC will enable applications and services to be hosted ‘on top’ of the mobile network elements (above the network layer) that can be accessed via various methodologies including PC5 as shown in the figure 2.3 above.

MEC uniquely allows software applications to tap into local content and realtime information about local-access network conditions. For example, Edge Computing can provide various vehicular services over the PC5 or Uu interface to provide High-Definition real-time maps, real-time traffic monitoring/alerts, and various entertainment content. MEC services can provide help in autonomous driving scenarios by providing access and alerts based on observed/detected road hazards and predictions based on local computing (such as weather condition-based or camera detection-based alerts, pedestrian crossing, and more).

With 5G C-V2X technology in mind, 5GAA has identified a group of new V2X applications and their service level requirements as shown in table above. A list of selected service examples from 5GAA’s “C-V2X Use Cases Volume II: Examples and Service Level Requirements” were presented with corresponding service requirements and the recommended C-V2X communication mode to fulfill the requirements. The PDF of that is available here.

The Release-16 description document has a summary of new V2X changes as shown below:

  • Advanced V2X support
    • Improvement of V2X service Handling: This WI introduces the requirements related to vehicle quality of service support, which enables a V2X application to be timely notified of expected or estimated change of quality of service (QoS). For example, when the communication packet error is expected to increase or decrease, the V2X application such as platooning application can increase or decrease inter-vehicle distance
    • Architecture enhancements for 3GPP support of advanced V2X services: Based on the requirements specified by V2XIMP in TS 22.185 and TS 22.186, the "Architecture enhancements to the 5G System" are specified in TS 23.287 [1] in order to facilitate vehicular communications for Vehicle-to-Everything (V2X) services. The following reference points are defined in the architectural reference models:
      • PC5 reference point: NR PC5 RAT, LTE PC5 RAT.
      • Uu reference point: NR, E-UTRA.
    • Application layer support for V2X services: The V2X application layer can be divided primarily into a V2X application specific layer which consists of V2X specific applications (e.g. Platooning, Vehicle safety) and a V2X application support layer which consists of V2X enabler services (e.g. V2X service discovery, message delivery, service continuity) and common enabler services (e.g. Group management, configuration management, location management).
    • 5G V2X with NR sidelink: 3GPP RAN technology for sidelink communication based on 5G NR was specified through this WI to define the means for providing the advanced V2X services identified by 3GPP SA1. This WI corresponds to 3GPP V2X phase 3, which is the evolution of LTE V2X in Release 14 (phase 1) and 15 (phase 2).

You can read more about it on The 3G4G Blog here.

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