5GAA | Safety of Life Study
The aim of this study is to explore the impact of different technical solutions for Cooperative Intelligent Transport Systems (C-ITS) communication solutions on EU road safety over time. Three different communication solutions are assessed independently and consist of:
- Cellular vehicle-to-everything (C-V2X) communication based on the evolved LTE technology as defined by 3GPP (a global cellular specifications body), divided into two solutions:
- LTE-PC5: Communication solution that uses direct-mode communication between vehicles, road users and infrastructure operating in ITS bands (e.g. ITS 5.9 GHz) independent of cellular network;
- LTE-Uu (cellular): Network-based communications interface (Uu) operating in the traditional mobile broadband licensed spectrum;
- 802.11p a Wi-Fi technology that supports Vehicle-to-vehicle (V2V) and Vehicle-to-Infrastructure (V2I) communications based on IEEE 802.11p and uses direct-mode communication operating in the ITS band of 5.9 GHz.
For the purpose of this study, LTE-PC5 and LTE-Uu will be modelled separately. However, it should be noted that these would likely co-exist. When assessing the results presented in this study, it should be considered that in reality, these two technical solutions could complement each other.
A key motivation for introducing C-ITS is the major potential to help improve road safety and decrease the number, as well as the severity, of accidents. For this study we have focused on two specific C-ITS use cases with high accident reduction potential that are on the European Commission’s list of priority C-ITS services. The selected services address vehicle-to-infrastructure (V2I) and pedestrian/cyclist to vehicle (V2P) communications:
- Red signal violation/intersection safety;
- Vulnerable Road User (VRU) protection.
The approach taken in this study separately models the penetration of new vehicles with C-ITS through built-in systems and that of additional equipment in existing vehicles through the driver’s smartphone (referred to as retrofitting).
We consider, as a baseline, the existing statistics of road traffic fatalities in the EU and then evaluate the potential reduction in the number of fatalities resulting from the deployment of each technical solution.
The modelling framework is kept in line with a previous 5GAA study and considers:
- The likelihood that any two ITS stations (vehicles, VRUs, roadside units (RSUs)) involved in a potential accident will be equipped with the same C-ITS communication solution.
- The fraction of fatalities which could be addressed and mitigated by the considered C-ITS communication solution.
- The likelihood that data transmitted from an ITS station via a given C-ITS communication solution is successfully communicated to its intended recipient.
- The effectiveness of a received alert/warning message inappropriately affecting the behaviour of the driver of a vehicle travelling towards a potential accident.
To account for the uncertainty in predicting the extent of future deployment and reliability of C-ITS technologies, we have developed “high” and “low” scenarios showing the sensitivity to key input parameters.
The aggregated results for both use cases (without the additional benefit arising from retrofitting of C ITS services through apps on smartphones used in vehicles) illustrate that in the high scenario LTE-Uu shows the highest benefits in terms of the number of avoided fatalities and serious injuries. By 2040 the number of fatalities and serious injuries avoided through the use of the LTE-Uu solution reaches 114,066, compared to 90,380 for LTE-PC5. For the 802.11p solution, the values are significantly lower at 27,144 as VRU protection is not supported through smartphones, leading to a low level of VRU protection (where VRUs are expected be equipped with C-ITS technology through their smartphones). Research carried out for this study showed that the integration of 802.11p into smartphones is highly unlikely; thus, the penetration in smartphones for this technical solution was set to zero.