Cellular V2X – Connecting Vehicles to everything

Introduction Cellular V2X 

(image source qualcomm.com)

Vehicular communication systems are networks in which vehicles and roadside units are the communicating nodes, providing each other with information, such as safety warnings and traffic information. They can be effective in avoiding accidents and traffic congestion. Both types of nodes are dedicated short-range communications (DSRC) devices. DSRC works in 5.9 GHz band with bandwidth of 75 MHz and approximate range of 300 m. Vehicular communications is usually developed as a part of intelligent transportation systems (ITS).[1]  Vehicular communication systems incorporates other more specific types of communication as Vehicle-to-everything (V2X) – V2I (Vehicle-to-Infrastructure), V2V (Vehicle-to-vehicle), V2P (Vehicle-to-Pedestrian), V2D (Vehicle-to-device) and V2G (Vehicle-to-grid).

Vehicle-to-everything (V2X) communication is the passing of information from a vehicle to any entity that may affect the vehicle, and vice versa. It is a vehicular communication system that incorporates other more specific types of communication as V2I (Vehicle-to-Infrastructure), V2V (Vehicle-to-vehicle), V2P (Vehicle-to-Pedestrian), V2D (Vehicle-to-device) and V2G (Vehicle-to-grid).[2]

DSRC was developed to meet all V2X requirements. It is the incumbent V2X technology, with huge planned investments in infrastructure. Vehicles with DSRC-based V2X can be bought today from GM and Toyota, and Volkswagen announced a plan for mass-market deployment starting 2019. Recently, C-V2X, a technology still in the making, is promoted by the cellular industry. No C-V2X products are available today, and are far from reaching the maturity and security levels needed for critical safety systems.

C-V2X directly connect vehicles to everything—including to each other (V2V), to pedestrians (V2P), and to roadway infrastructure (V2I), and to the network (V2N). C-V2X technology complements other vehicle sensor technologies, extending a vehicle’s ability to “see” further down the road and providing a higher level of predictability for enhanced safety and autonomous driving.

(image source qualcomm.com)

Technology

More than 800 mobile operators around the world have deployed networks that are compatible with the 3GPP standards, enabling them to benefit from global interoperability and economies of scale. In June 2017, 3GPP finalised Cellular Vehicle-to Everything (C-V2X) technology in Release 14 of its standards. Based on LTE, this cellular technology is designed to deliver safety and information services to vehicles, paving the way for the development of cooperative intelligent transport systems (C-ITS) that reduce congestion and pollution, while making travel faster and more efficient.

Cellular V2X (C-V2X) is the technology developed in 3GPP1 and is designed to operate in two modes:

• Device-to-device: This is Vehicle-to-Vehicle (V2V), Vehicle-to-(Roadway) Infrastructure (V2I) and Vehicle-to-Pedestrian (V2P) direct communication without necessarily relying on network involvement for scheduling.
  Device-to-network: This is Vehicle-to-Network (V2N) communication which uses the traditional cellular links to enable cloud services to be part of the end-to-end solution by means of network slicing architecture for vertical industries.

(image source qualcomm.com)

As experienced, trusted and licensed providers of connectivity, mobile operators are capable of meeting the automotive industry’s need for scalable, secure and proven solutions. Mobile operators have a long track record of deploying and managing secure, reliable and comprehensive end-to-end communication services and coverage. For the connected vehicle market to scale to its full potential, drivers need to trust the security and reliability of all components and layers of connected vehicles. Mobile operators can work with automakers and other stakeholders.

what mobile operators can offer:

• Broad coverage via existing cellular networks.
• Extensive experience in deploying,managing, and maintaining complexcommunication systems.
• Complementary services, such as navigation, pay-as-you-drive insuranceand vehicle diagnostics
• Public key infrastructure (PKI) certificate management
• Data storage and data analytics

The Role of C-V2X

In June 2017, the mobile industry body 3rd Generation Partnership Project (3GPP), standardised a set of technologies specifically designed to enable communications between vehicles and roadside infrastructure. Known as Cellular Vehicle-to-Everything (C-V2X), these technologies can enhance safety and ultimately support autonomous driving by:

• Leveraging the comprehensive coverage of secure and already established LTE networks.
• Enabling highly reliable, real-time communication at high speeds and in high-density traffic
• Supporting short and long range transmissions between vehicles and roadside infrastructure

By providing real-time information on conditions beyond the driver’s line of sight, C-V2X can work with other sensors on-board a vehicle to increase safety. The information captured by a C-V2X system can complement the data being captured by radar, lidar and ultrasonic systems that help the driver to keep the vehicle a safe distance from the vehicle in front and contend with bad weather conditions and low light situations. A vehicle’s on-board computer can combine data received via C-V2X with information captured by on-board cameras to interpret road signs and objects.[4]

How C-V2X can improve drivers safety

Scenarios in which C-V2X can help to enhance safety.

Platooning : refers to the formation of a convoy in which the vehicles are much closer together than can be safely achieved with human drivers. Such automated convoys make better use of road space, save fuel and make the transport of goods more efficient.

Co-operative driving: Vehicles can use C-V2X to work together to make the best use of the available road space and minimise the disruption caused by lane changes and sudden braking. C-V2X can be used to convey intent to other road users.

Queue warning: Roadside infrastructure can also use C-V2X to warn vehicles of queues or road works ahead of them, so they can slow down smoothly and avoid hard braking.

Avoiding collisions: Each vehicle on the road could use C-V2X to broadcast its identity, position, speed and direction. An on-board computer could combine that data with that from other vehicles to build its own realtime map of the immediate surroundings and determine whether any other vehicle is on a potential collision
trajectory.

(image source qualcomm.com)

Hazards ahead warning: C-V2X can be used to extend a vehicle’s electronic horizon, so it can detect hazards around a blind corner, obscured by fog or other obstructions, such as high vehicles or undulations in the landscape. Roadside signs could use C-V2X to broadcast hazard warnings to each vehicle on a particular stretch of road.

Increasingly autonomous driving: Along with other sensors and communications systems, C-V2X will play an important role in enabling vehicles to become increasingly autonomous.[5]

Some Key Feature of C-V2X are

Non-line of sight sensing
Provides 360º non-line-of-sight awareness, e.g. at blind intersections/on-ramps.

Conveying intent
Communicates intent and shares sensor data to provide higher level of predictability.

Enhanced situational awareness
Offers increased electronic horizon to enable soft safety alerts and reliable graduated warning.

Secure communications
Enables secure, low latency V2X communications for active safety and enhanced situational awareness.

Precise positioning
Provides precise positioning and timing that are necessary for cars to communicate their accurate position, speed and heading.

Efficient processing
Provides complete CV2X solution, including running the Intelligent Transportation Systems (ITS) V2X stack and secure communications.

The Advantages of C-V2X

C-V2X has several major advantages over other vehicle connectivity solutions for each of the
key stakeholders in this sector.

For automakers: Combining secure wide area and short-range connectivity in one technology, C-V2X is a versatile and cost-effective solution for automakers looking to improve road safety.

For road operators: As the ITS band uses high frequency spectrum (5.9 GHz), in which radio signals have a limited range, providing extensive connectivity coverage is challenging for road operators. However, C-V2X allows for direct communications in the 5.9 GHz band to be supplemented with cellular communications
using lower frequencies in which radio signals travel further.

For mobile operators: To keep deployment costs down, mobile operators can harness their existing cellular infrastructure to support the rollout of C-V2X connectivity. The synergies between the roadside infrastructure and the conventional cellular infrastructure can generate significant economic benefits.

C-V2X has a number of technical advantages over 802.11p-based alternatives, as summarised in the graphic
below:

C-V2X offers superior performance over IEEE 802.11p

Based on the recently completed 3GPP Release 14 specification, C-V2X offers superior performance over IEEE 802.11p – an amendment to the IEEE 802.11 standard defining enhancements to support Intelligent Transportation Systems (ITS) applications, also referred to as DSRC (Dedicated Short-Range Communications) from the related project of the US Department of Transportation which considered IEEE 802.11p – with respect to coverage, mobility support, delay, reliability and scalability, which makes C-V2X the most suitable candidate in the 5.9 GHz ITS spectrum to meet the near-term vehicular communication requirements.[3]

In addition to its performance advantages, C-V2X – as part of the 3GPP standards family – offers an evolution path to 5G which will enhance the 3GPP Release 14 specification through its highly reliable and low-latency mission critical service design for V2X applications and, thus, will provide the required technology roadmap for enabling ADAS and CAD. Finally, it is important to note that C-V2X can leverage well-designed and tested upper layer specifications from ETSI, ISO, SAE and IEEE. In this way, the latest 3GPP specified PHY and MAC can be used together with legacy C-ITS specifications to enable the best possible V2X deployments in the 5.9 GHz spectrum as early as 2018.

Since C-V2X can offer both device-to-device (V2V, V2I and V2P) and device-to-network (V2N) services which will transform connected transportation around the globe, it is important to consider the spectrum that needs to be utilized for that purpose. As the 5.9 GHz ITS spectrum is clearly emerging as the primary common global spectrum to be used for basic safety applications around the world, it is of major importance that the use of C-V2X direct communication in 5.9 GHz is secured in order to guarantee that the superior C-V2X technology advantages can be used both near- and long-term for the public good. In this way, C-V2X services will not only find their way to the market and the public through the use of the 5.9 GHz ITS spectrum, but they will also motivate the use of commercial cellular bands for additional non-ITS V2X use cases to complement the safety services predominantly provided in the 5.9 GHz ITS spectrum.[3]

Summary 

Now that C-V2X technology has been standardised, it is set to be widely adopted by vehicle manufacturers and mobile operators, paving the way for deployments around the world by road operators and municipalities. C-V2X is expected to be instrumental in transforming connected transportation services throughout the globe. C-V2X direct communications can operate both in ITS spectrum and in commercial cellular spectrum, combined with network-based C-V2X communications operating on existing and future cellular networks. The newly formed 5GAA is a clear proof of the existence of a strong ecosystem of leading automotive and telecommunication companies which is confident that a technically superior standards-based, cost-effective and scalable access technology from the cellular industry will carry C-ITS and Connected Vehicle applications well into the 5G era and beyond. From 2018, C-V2X systems will begin to go live in China, Europe and North America. As a matter of urgency, governments and public agencies need to ensure that there are no regulatory barriers preventing the widespread adoption of C-V2X.

With a flexible and future-proof regulatory framework, C-V2X will help to transform road transport, delivering numerous socio-economic and environmental benefits along the way.

References:

[1] https://en.wikipedia.org/wiki/Vehicular_communication_systems

[2] https://en.wikipedia.org/wiki/Vehicle-to-everything

[3] https://5g.ieee.org/tech-focus/june-2017/cellular-v2x

[4] https://www.auto-talks.com/technology/dsrc-vs-c-v2x-2/

[5] https://www.gsma.com