Cellular V2X uses
3GPP standardised
4GLTE or
5G mobile cellular connectivity to exchange messages between vehicles, pedestrians, and wayside traffic control devices such as traffic signals. It commonly uses the 5.9 GHz frequency band, which is the officially designated
intelligent transportation system (ITS) frequency in most countries. C-V2X can function without network assistance and exceeds the range of
DSRC by about 25%.[2]
C-V2X was developed within the 3GPP[1] to replace DSRC in the US and C-ITS in Europe.[3]
History
In 2014, 3GPP Release 13 spurred studies to test the applicability of the then current standards to V2X. This resulted in the 3GPP Release 14 specifications for C-V2X communications, finalised in 2017. 3GPP Release 15 introduced 5G for V2N use-cases and 3GPP Release 16 includes work on 5G NR direct communications for V2V/V2I.[4]
In Europe, the
EU announced in July 2019 that it was adopting a technology-neutral approach to C-ITS, leaving the way forward for
4G,
5G and other advanced technologies to be part of V2X applications and services.[5]
In the United States, the
Federal Communications Commission proposed late in 2019 that 20 MHz and possibly 30 MHz of the 5.9 GHz band be allocated to C-V2X.[6] In November 2020, this proposal was accepted, and the upper 30 MHz (5.895–5.925 GHz) were allocated to C-V2X.[7]
Modes
C-V2X has the following modes:
Device-to-network: communication using conventional cellular links for vehicle-to-network (V2N) applications such as cloud services in end-to-end solutions[jargon]
Device-to-device: direct communication without the use of network scheduling for
vehicle-to-vehicle (V2V),[8] vehicle-to-infrastructure (V2I), and vehicle-to-pedestrian (V2P) [8] applications such as vulnerable road user protection and
tolling[9]
C-V2X mode 4 communication relies on a distributed resource allocation scheme, namely sensing-based semipersistent scheduling which schedules radio resources in a stand-alone fashion in each user equipment (UE).[10]
Problems
All the
communications systems based on
wireless communication suffer from the drawbacks,
inherent to wireless communication, which are the limited capacities in various areas:
Wireless communication is susceptible to external influences, which may be hostile.[13]
In metropolitan areas, limits of data propagation due to surroundings such as
buildings,
tunnels[14] and also
Doppler effects, causing propagation speed reduction by repetitive transmissions required.
The costs to provide a comprehensive appropriate network such as
LTE or
5G are enormous.[15]
The solution to handle the flow of data is expected to come from
artificial intelligence.[16][17] Doubts in artificial intelligence (AI) and decision making by AI exist.[18]
^Hong-Chuan Yang, Mohamed-Slim Alouini (24 May 2018). "Wireless Transmission of Big Data: Data-Oriented Performance Limits and Their Applications".
arXiv:1805.09923 [
eess.SP].