# On the Needs and Requirements Arising from Connected and Automated Driving
## 5 Relationship to 3 GPP KPIs and the Role of 5 GAA  
3 GPP TS 22.186 [20] and the corresponding technical report TR 22.886 [13] were developed within Rel. 15 with focus on the description of advanced V2X use cases, when considering automated driving that requires more challenging performance requirements for the 3 GPP system, including more strict functional requirements for advanced features. Before, within Rel. 14, 3 GPP had introduced 22.185 [21] and 22.885 [22] for efficient support of basic ITS services using LTE-V2X. [20] has considered use cases that belong to the following groups: (a) Vehicle Platooning, (b) Extended Sensors, (c) Advanced Driving, (d) Remote Driving, and (e) General Aspects, including interworking, multi-RAT, communication-related requirements. For each of the use cases that belong to the above groups, the following performance requirements have been discussed: (a) payload (Bytes) without considering the security payload (i.e., application layer message size), (b) end-to-end latency (ms), without considering application layer processing delay, (c) reliability (%), (d) data rate (Mbps), (e) communication range (m), and (f) transmission rate (message/s). Table 3 highlights the range of the 3 GPP KPIs for each identified category. Automated driving sets the most stringent performance requirements for the communication layer in terms of delay, reliability, and capacity due to the safety requirements. As vehicles advance towards higher automation levels, they will have to deal with increasingly complex road situations and, therefore, the need for a complementary communication technology for the exchange of cooperative information with higher bandwidth and improved reliability will increase. The use cases and the requirements that have been proposed in the 5 GCAR project are, in many cases, different from the descriptions and/or the KPI values that have been proposed in 3 GPP. The 5 GCAR project elaborated on more concrete use cases than the ones defined by 3 GPP, which were the outcome of consensus discussions mostly between the 5 GAA organization and the traditional stakeholders of 3 GPP. Accordingly, although particularly well documented, the 3 GPP use cases were kept at quite a generic level (see for instance in Table 3 the range of some parameters). Indeed, the use cases elaborated by 5 GCAR were also defined with concrete applications in mind and they were demonstrated at the end of the project [23]. Moreover, 3 GPP has not focused on the analysis of automotive requirements, since the focus lies at the communication layer. An analysis of the differences between the 5 GCAR use cases and the corresponding 3 GPP use cases is provided below:  
* The 5 GCAR **lane merging** use case introduces additional network requirements regarding the expected latency and transmission range, which have not been set in 3 GPP [20]. In addition, the 5 GCAR reliability requirement is more demanding, while the 5 GCAR data rate requirement is lower, mainly due to the different adopted approaches for the calculation of exchanged trajectories. * The description of the 5 GCAR **see-through** use case is the same as the corresponding 3 GPP use case, which is entitled as \"Video sharing between UEs supporting V2X application\" in 3 GPP \begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Use Case Group** & **Payload (Bytes)** & **Latency (ms)** & **Reliability (\%)** & **Data Rate (Mbps)** \\ \hline Vehicle Platooning & 50–6500 & 10–20 & 90–99.99 & 0.012–65 \\ \hline Advanced Driving & 300–12000 & 3–100 & 90–99.999 & 0.096–53 \\ \hline Extended Sensors & 1600 & 3–100 & 90–99.999 & 10–1000 \\ \hline Remote Driving & - & 5 & 99.999 &
\begin{tabular}{} \end{tabular} \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Summary of V2X Performance Requirements in 3 GPP TS 22.186. TS [20]. The differences reside at the data rate (14-29 Mbps in 5 GCAR instead of 10 Mbps for the lower level of automation in 3 GPP) and reliability values (99.9% in 5 GCAR instead of 90% in 3 GPP).