Introductory Chapter: Vehicles Everywhere, and Vehicular Communications Should Follow!

1. Introduction—Vehicles everywhere!

The vehicles played a major role in the evolution of the human life and the industrial/modern society. Helping people to travel and carry merchandise over distances in a short time and in increasing comfort, they did not stop their evolution toward unbelievable and unprecedented manner. In the recent years, vehicles started assisting drivers in the driving, with the long-term objective to overtake the entire driving operations in an autonomous way to reach the full autonomous driving vehicles.

While autonomous driving vehicles are still competing to gain ground in the practice on public roads and fulfill the security requirements, autonomous vehicles have already been established in industrial applications. Different brilliant examples can be cited, as illustrated in Figure 1. Unmanned aerial vehicles (UAV) or drones are gaining increasing interest in different applications domains, such as the delivery tasks. The delivery items can be products purchased through online shopping or medical products in emergency situations, such as catastrophes/floods/etc., or accidents in difficult accessibly locations. A second example is the automated guided vehicles (AGV). These have a spread utilization in different industrial domains, such as the AGVs used to transport containers on maritime ports arrays or the AGVs used in the warehouses of giant online trade enterprises. Last but not least, the autonomous maritime vehicles, that is. vessels or ships, are new innovative solution to optimize the maritime transport of goods. The autonomy of the vessels can be one of four levels as defined by the International Maritime Organizations (IMO), as discussed in Ref. [1]:

• Degree one: Ship with automated processes and decision support: Seafarers are on board to operate and control shipboard systems and functions. Some operations may be automated and at times be unsupervised but with seafarers on board ready to take control.

• Degree two: Remotely controlled ship with seafarers on board: The ship is controlled and operated from another location. Seafarers are available on board to take control and to operate the shipboard systems and functions.

• Degree three: Remotely controlled ship without seafarers on board: The ship is controlled and operated from another location. There are no seafarers on board.

• Degree four: Fully autonomous ship: The operating system of the ship is able to make decisions and determine actions by itself.

Figure 1.

Vehicles on roads, in the air, in seaports, on the sea, in warehouses and all need to communicate with their environments or remote servers [1, 2, 3].

All these types of autonomous vehicles require efficient and highly reliable vehicular communications to exchange data and commands with its neighborhoods, in form of other vehicles, sensors, machines (on wheels), the servers in the remote control centers, etc.

2. Internet of vehicles

The term “Internet of Vehicles” (IoV) refers to the integration of vehicles with the Internet and other communication technologies to enable them to communicate with each other, with infrastructure, and with various services. IoV aims to enhance the safety, efficiency, and overall experience of transportation through the use of connected devices and advanced communication technologies. As illustrated in Figure 2, IoV is the evolution of the concept of vehicular communications (initially known as vehicle-to-vehicle or V2V). Its objectives are to cover a wider range of interactions between the vehicles and their environments (neighborhoods and remote servers/control centers) to cover: Vehicles and Personal Services (V&P), vehicle-to-vehicle (V2V), vehicle and roadside (V&R), vehicle and sensor (V&S), and vehicle and infrastructure (V&I or V2I) [4, 5].

Figure 2.

Evolution of evolution of vehicular communications in form of V2X in LTE/4G (left) toward Internet of Vehicles (IoV) in 5G and Beyond-5G (right).

Generally, the key components of the Internet of Vehicles include:

• Vehicular communication: Vehicles equipped with communication devices (such as sensors, GPS, and communication modules) can exchange information with each other and with the surrounding infrastructure. This communication can be used for various purposes, including traffic management, collision avoidance, and cooperative driving.

• Infrastructure integration: IoV involves integrating vehicles with the existing transportation infrastructure, such as traffic lights, road signs, and other roadside systems. This integration allows for better traffic management, improved safety, and enhanced overall transportation efficiency.

• Data exchange and processing: IoV relies heavily on the exchange of data between vehicles and infrastructure. This data can include information about traffic conditions, road hazards, and the status of other vehicles. Advanced data processing and analysis are essential for making real-time decisions and optimizing transportation systems.

• Intelligent transportation systems (ITS): The notion of IoV is closely related to intelligent transportation systems, which use different technologies to manage and optimize transportation networks. The ITS involves the application of information and communication technologies to transportation infrastructure and vehicles to improve safety, mobility, and environmental sustainability.

• Safety and collision avoidance: One of the primary goals of IoV is to improve road safety. Connected vehicles can share information about their speed, location, and other relevant data, enabling systems that can warn drivers about potential collisions or hazardous road conditions.

• Autonomous vehicles: IoV plays a crucial role in the development and deployment of autonomous vehicles. Connected vehicles can share data to improve the decision-making process of autonomous systems, enhancing their ability to navigate and respond to dynamic traffic conditions.

• Enhanced driver experience: IoV can offer various services to enhance the overall driving experience, such as real-time navigation updates, predictive maintenance alerts, and in-vehicle entertainment options.

• Sensors and connectivity: IoV relies on sensors, such as GPS, radar, and cameras, installed in vehicles to collect and transmit data. Connectivity is achieved through technologies, such as cellular networks and dedicated short-range communication (DSRC) systems.

• Data analytics and cloud computing: The massive amount of data generated by connected vehicles is processed and analyzed advanced technologies, which covers data analytics and cloud computing technologies. This enables real-time decision-making, predictive maintenance, and the development of intelligent transportation systems.

The Internet of Vehicles is part of the broader concept of the Internet of Things (IoT), where everyday objects are connected to the Internet to enable communication and data exchange. The implementation of IoV has the potential to revolutionize transportation by making it safer, more efficient, and more sustainable. The IoV may include also other vehicle types, such as those cited in the previous section, as shown in Figure 3. This example includes unmanned aerial vehicles or drones in different forms and types. Either such UAV can be an operational vehicle with specific tasks such as delivery, video surveillance, etc. or it can be a part of communications infrastructure, such as the UAV serving as a base station for the mobile cellular communications [6].

Figure 3.

Vehicular communications covers also unmanned aerial vehicles (UAVs) interacting/communicating with personal cars, busses, trucks, etc.

3. Vehicular communications

Vehicular communication refers to the exchange of information between vehicles and between vehicles and roadside infrastructure. This communication is typically facilitated by wireless technology, allowing vehicles to communicate with each other and with the surrounding infrastructure to improve road safety, traffic efficiency, and overall transportation systems. In general, there are two main types of vehicular communication:

• Vehicle-to-vehicle (V2V) communication: In V2V communication, vehicles exchange information directly with each other. This can include data about the vehicle’s speed, position, acceleration, and other relevant parameters. The goal is to enhance safety by allowing vehicles to be aware of each other’s presence and take appropriate actions to avoid collisions. For example, if one vehicle detects a potential collision with another, it can alert the driver or even take autonomous actions to prevent an accident.

• Vehicle-to-infrastructure (V2I) communication: V2I communication involves the exchange of information between vehicles and roadside infrastructure such as traffic lights, road signs, and other intelligent transportation systems. This communication can provide drivers with real-time information about traffic conditions, road closures, or other relevant updates. It also allows the infrastructure to communicate with vehicles, optimizing traffic flow and improving overall transportation efficiency.

3.1 Vehicular communications is a complex landscape

Vehicular communications, also known as V2X (Vehicle-to-everything) communication, involve the exchange of information between vehicles and other entities such as infrastructure, pedestrians, and the surrounding environment. Various types of vehicles benefit from vehicular communications, and these technologies play a crucial role in improving road safety, traffic efficiency, and overall transportation systems. The types of vehicles that can benefit from vehicular communications include:

• Passenger vehicles: Standard automobiles equipped with communication capabilities can benefit from V2X communication for enhanced safety and improved traffic flow.

• Commercial vehicles: Trucks, buses, and other commercial vehicles can use vehicular communications to optimize logistics, improve fuel efficiency, and enhance overall fleet management.

• Public transport: Buses and other public transportation vehicles can utilize V2X communication to improve passenger safety, provide real-time transit information, and optimize public transit routes.

• Emergency vehicles: Ambulances, fire trucks, and police vehicles can use vehicular communications to prioritize their movement through traffic, improving emergency response times.

• Cyclists and motorcyclists: V2X communication can enhance the safety of cyclists and motorcyclists by alerting other vehicles about their presence, especially in blind spots.

• Pedestrians: Pedestrians equipped with smart devices or wearables can interact with vehicles equipped with V2X technology, enhancing safety at crosswalks and intersections.

• Autonomous vehicles: Self-driving or autonomous vehicles heavily rely on V2X communication to share information with other vehicles, infrastructure, and pedestrians to navigate safely and efficiently.

• Infrastructure (V2I): Roadside infrastructure, such as traffic lights, signs, and sensors, can communicate with vehicles to provide real-time traffic information and signal timing to enhance the overall traffic management.

• Specialized vehicles: Vehicles used in specialized contexts, such as construction vehicles or agricultural machinery, can benefit from V2X communication to improve coordination and safety.

• Electric vehicles (EVs): Electric vehicles can use V2X communication to optimize charging schedules, share information about charging station availability, and coordinate with the power grid.

• Delivery vehicles: Vehicles involved in package delivery and logistics can use V2X communication to optimize delivery routes, reduce congestion, and improve efficiency.

• Car-sharing and ride-sharing vehicles: Vehicles involved in car-sharing and ride-sharing services can benefit from V2X communication to enhance safety and optimize pick-up and drop-off locations.

• Unmanned aerial vehicles (UAV) /Drones: UAV can be either an operational vehicle with specific tasks such as delivery, video surveillance, etc., or it can be a part of communications infrastructure, such as the UAV serving as base station for the mobile cellular communications.

• Automated guided vehicles (AGV): These have a large utilization in different industrial domains, such as the AGVs used to transport containers on maritime port arrays.

Vehicular communications are a key enabler for the development of intelligent transportation systems (ITS), providing a networked environment where vehicles and infrastructure work together to improve road safety, traffic flow, and overall transportation efficiency. The integration of V2X technologies contributes to the development of connected and autonomous vehicles and helps build more intelligent and responsive transportation networks.

3.2 Challenges for vehicular communications

While vehicular communication holds great promise for improving road safety and traffic efficiency, there are several challenges that need to be addressed for its successful implementation. Some of the key challenges include:

• Quality of service (Throughput, Reliability, and Low Latency): Vehicular communication systems require low-latency and high-reliability communication to support safety-critical applications. Delays in transmitting and receiving messages could lead to accidents.

• Security and privacy concerns: Ensuring the security of vehicular communication systems is crucial to prevent unauthorized access, cyberattacks, and data breaches. Additionally, preserving the privacy of drivers and their data is a significant concern.

• Scalability: As the number of connected vehicles increases, the vehicular communication system must be able to scale to handle a growing volume of data and connections without compromising performance.

• Interoperability: Achieving interoperability between different manufacturers and models of vehicles is a challenge. Standardization of communication protocols and data formats is essential to ensure seamless communication between diverse vehicles and infrastructure.

• Spectrum allocation: The availability and allocation of suitable radio frequency spectrum for vehicular communication is a critical issue. As more devices and systems compete for limited spectrum resources, the interference management and the guarantee of reliable communication become very challenging.

• Environmental factors: Vehicular communication systems must contend with various environmental factors, such as interference from buildings, terrain, and other obstacles. Adverse weather conditions, such as heavy rain or snow, can also affect signal quality.

• Infrastructure deployment: The deployment of roadside infrastructure, such as communication hubs and sensors, can be logistically challenging and costly. Achieving widespread coverage in both urban and rural areas is essential for the success of vehicular communication systems.

• Human factor considerations: Human behavior, including drivers’ acceptance of and adherence to vehicular communication systems, is a critical factor. Educating drivers about the benefits and usage of these systems is crucial for their effective implementation.

• Regulatory and legal issues: Developing and enforcing regulations related to vehicular communication is a complex task. Legal frameworks must be established to govern issues such as liability, data ownership, and compliance with safety standards.

Addressing these challenges requires collaboration among stakeholders, including automobile manufacturers, government agencies, communication technology providers, and standardization bodies. Continuous research and development efforts are necessary to overcome these obstacles and realize the full potential of vehicular communication systems.

3.3 Technologies and standards for vehicular communications

Several standards have been developed over the years to govern vehicular communications, ensuring interoperability, security, and consistency across different systems. A possible categorization of these standards is illustrated in Figure 4, based on a proposition from [7], showing three main categories:

Figure 4.

General classification of wireless communications technologies for vehicular communications and applications, extension based on [7].

The (traditional) vehicular communications: this class includes some of the first solutions for vehicle-to-vehicle communications, with:

1. IEEE 802.11p (Wireless Access in Vehicular Environments - WAVE): IEEE 802.11p is an amendment to the IEEE 802.11 standard that specifically addresses wireless communication in vehicular environments. It defines the use of the 5.9 GHz frequency band for dedicated short-range communication (DSRC), supporting V2V and V2I communication. IEEE 802.11bd (Next-Generation V2X - NGV): Under development, IEEE 802.11bd aims to provide advancements beyond IEEE 802.11p with improved performance and new features for next-generation V2X (Vehicle-to-everything) communication. IEEE 1609 Family (Wireless Access in Vehicular Environments - WAVE Standards): The IEEE 1609 family includes a set of standards for WAVE (Wireless Access in Vehicular Environments), covering various aspects of vehicular communication, including networking, security, and message sets.

2. ISO 24102 (Intelligent Transport Systems - Communication Access for Land Mobiles (CALM) - Facilitation of Traffic Management): ISO 24102 provides standards for the communication access for land mobiles (CALM) to facilitate traffic management in intelligent transport systems.

The most dynamic category is the one including the cellular technologies referred sometimes as cellular V2X (C-V2X), such as satellites and WiMAX (IEEE 802.16). However, the most dynamic and innovative solutions are included in standards developed by the third generation partnership project (3GPP) [8]. The vehicular solutions for vehicle communications started with use cases in form of device-to-device (D2D) solution in long-term evolution (LTE) referred as 4G to. This solution evolved in its following generation long- term evolution-advanced pro (LTE-A Pro/4,5G) and reaches its maturity within 5G.

The last category is the short distance wireless communication technologies, which are network protocols in which remote nodes are connected over very short distances. Short-range radio communication can minimize power, volume, heat, and cost. The most known technologies of this category are WIFI (IEEE 802.11), ZigBee, and Bluetooth in both versions the legacy Bluetooth and modern version Bluetooth Low Energy (BLE).

These standards play a crucial role in ensuring that different vehicles and infrastructure components can communicate effectively, promoting safety, efficiency, and interoperability in vehicular communication systems. It is important to note that standards may continue to evolve as technology advances and new requirements emerge. It is important to note that standards may vary regionally, and different countries or organizations may adopt specific standards based on their regulatory and technical requirements. Additionally, the field of vehicular communications is dynamic, with ongoing developments and updates to standards to address emerging challenges and technologies. Therefore, the ongoing works on 3GPP standards for the sixth generation of mobile cellular communications networks (6G) are considering more complex use cases and configurations in Internet of Vehicles scenarios [9]. Such future architecture covers three layers that are completing each other and interacting, as shown in Figure 5.

Figure 5.

Vehicular communications and IoV in the heart of development scenarios for the future generation of mobile networks 6G.

4. Conclusions

Vehicles are present everywhere in our daily life, in our industries, and societies. The Internet of Vehicles represents an innovative solution to connect all types of vehicles with the neighborhoods and infrastructures. In the paradigm of Internet of Vehicles, vehicular communications play a key role and must fulfill a long list of requirements. Therefore, different categories of wireless communications have been developed over the time. Standards, especially those issued from 3GPP with its work on the sixth generation of mobile communications (6G), are continuing its adaptability to the new service requirements and challenges to offer an economically viable, highly reliable, and performing adaptive communications solution.

Conflict of interest

The authors declare no conflict of interest.