# What is 5G? Emerging 5G Mobile Services and Network Requirements
## 4 5G Mobile Services
### Autonomous 5G services  
#### 4.4.1 Smart transportation  
The concept of smart transportation refers to a transportation system that enables improved safety, higher productivity and efficiency with the help of a network infrastructure. 5G combined with artificial intelligence (AI) algorithms is one of the main enabling technologies for such smart transportation systems. Connected cars and RSUs will offer services of collision avoidance and route optimization under a dedicated transport network with high security, high performance and cloud computing. As shown in Figure 9, the use cases in the automotive domain that are relevant for 5G include: autonomous driving vehicles, vehicle platooning and traffic safety and control [22]. With the advent of automated driving functions, especially with the broad availability of vehicles capable of supporting higher automation levels, autonomous-driving cars are the future of smart transportation [23; 24]. Autonomous-driving cars have the intelligence to recognize, decide and control accordingly. Enhanced V2X communications and autonomous functions are designed to avoid accidents caused by human error. The concept of vehicle platooning refers to vehicles traveling together by following a lead vehicle. This leads to increased safety and comfort, reduced traffic congestion and efficiency improvement. Vehicle platooning can be easily implemented through communication with 5G base stations and vehicle-to-vehicle communications. 5G base-stations can figure out the location and speed information of vehicles in real time through 5G with low latency and can support maintaining the minimum distance between cars. Traffic safety and control include all the services to ensure maximum safety in any type of situation. These applications include large-file and real-time data exchange and, in the case of passenger terminals, real-time information, entertainment systems and video advertising. V2X and some other intelligent transportation systems (ITS) applications require very low latency; much lower than the one provided by current technologies. In addition, driverless and next-generation driver-assisted cars will need real-time safety systems that can exchange data with other vehicles and a fixed infrastructure around them. These types of cars need to process at least 1 Gbps of data rate to make smart decisions. However, current technologies cannot support the simultaneous transmission and reception at such a high data rate among thousands of cars within a small area. Therefore, 5G technology is essential for providing real-time services in future vehicles, and baking low latency  
Figure 8: Smart personal, building and city services with IoT.  
into the design of 5G networks will open up the potentially large market of smart transportation for wireless operators. Localization is also one of the significant requirements for autonomous-driving vehicles to acquire the accurate information around the vehicles.  
Cellular V2X (C-V2X) provides connectivity between vehicles and everything with enhanced architectures and features based on cellular technologies [25]. In 5G, C-V2X can use both below the 6-GHz band for high service reliability and above the 6-GHz band, e.g., millimeter wave, for high volume data transfer, while also providing low latency wide area network support for assisted driving. Additionally, C-V2X direct communications can operate in the 5.9-GHz ITS spectrum band, which is used by IEEE 802.11p-based WAVE technology, without cellular subscription requirement for direct safety communications. Though the coexistence of C-V2X and IEEE 802.11p-based WAVE can be considered, C-V2X may be preferred as a 3 GPP standard because C-V2X can provide a direct evolution path from LTE to 5G and can support all V2X applications with the same technology.