The field of communication today is flourishing with extravagant devices. Communication is a bare necessity not only for us but also for our machines. In specific regards to our vehicles, communication among them can be a boon to road safety. Our vehicles communicating with the infrastructure around and managing the road traffic lay a supreme foundation for smart cities. By far this phenomenon of a vehicle to infrastructure communication is real and is present in a handful of places in the world. It is estimated to grow with time at a steep rate. So what exactly is Vehicle to Infrastructure communication (V2I)? Colloquially speaking it’s the wireless exchange of data between the vehicles and the road infrastructure. It provides advisories and warning to the driver seeing his safety, mobility and environment-related conditions. It is a step up to an intelligent transport system.

V2I technologies ensure seamless flow of data to collaborate between vehicles, infrastructure, pedestrians this not only provides relative information but can also provide information about the weather, road conditions, traffic conditions, or even accidents. The motive is to move over a collaborated safe environment where your vehicle is able to collaborate and communicate with other cars. Apart from safety, it can also be used for automatic payments of Parking, Toll charges etc.

Future of Vehicle to Infrastructure Technologies:

V2I is expected to grow exponentially, as more and more devices are getting connected to grid(Infrastructure), these things are laying foundations of future connected Systems. V2I systems will play an essential role in Autonomous cars, where the environment has to be a part of the ecosystem, this integration will be soon part of the features presented by Vehicle manufacturers many of them have already planned to integrate the technologies in future models.

The network should not only work under Non-Line of Sight conditions but also up to a range of 100 meters. These systems should work with high traffic congestion, bad weather or potential hazards with high accuracy.

Classification of V2I:

V2I can be broadly divided into two aspects:

Safety Applications:

Non-Safety Applications

  1. SAFETY Applications in V2I: An application designed to work for safety critical environment should not only consider steady data transmission but also Minimum Latency. Most of these applications will be safety critical and can avoid an accident between vehicle, pedestrian or other so functional safety is of paramount importance.
  2. NON SAFETY Applications: These applications will not require extensive testing of functional safety but will also be a part of Vehicle infrastructure. One such example can be sharing of an event nearby or paying for a Parking lot.


The Dedicated Short Range Communication is a bipolar wireless communication technology that permits very high data transmission, crucial in safety applications. In 1999 the Federal Communication Commission has set aside the 75 megaHz of spectrum around the 5.9 gigaHz to be used for the vehicle-related safety system. It is used for V2I communications because it has secure transmission, low latency, fast network acquisition and the ability to handle rapid and frequent handovers that are inherent in a vehicle environment. It can also sustain severe weather conditions.

The DSRC consists of

  1. On-Board Unit or Equipment (OBU) -Initially the onboard units consisted of GPS and a storage device. Nowadays it accumulates information from multiple sensors and manages data at a very high speed and also performs real-time communication.
  2. The OBU has two correlated paths which are
  • Connectivity- the amount and types of ports available to connect with other devices
  • Processing Capacity- the capacity of the CPU to manage complex functionalities.

OBUs provide communication both between the roadside unit and vehicle and between nearby vehicles. They are the vehicle side of V2I communication.

  1. Roadside Unit or Equipment (RSU) –Roadside Unit is mounted at intersections and interchanges. It provides an interface to the vehicle within their range through an additional interface, it provides the local infrastructure applications safety. It allows information to be passed between the vehicles and infrastructure and other devices by transferring data through DSRC as per the industry norms. It can also be added to a backhaul system to facilitate distance management. It ensures that the available bandwidth for the transmission of data is not exceeded. It manages prioritisation of messages to and fro the vehicle.

Other Wireless Protocols

  1. Bluetooth- It is a wireless communication technology that allows sharing of data within short distances. It creates an ad hoc network. The range of Bluetooth is very application specific. Range may vary depending on class of radio used in an implementation:
  • Class 3 radios – have a range of up to 1 meter or 3 feet
  • Class 2 radios – most commonly found in mobile devices – have a range of 10 meters or 33 feet
  • Class 1 radios – used primarily in industrial use cases – have a range of 100 meters or 300 feet

In the automobile industry, the supreme use of Bluetooth is connecting to hands-free car system which helps the driver focus on the road. If paired with the in-vehicle interface it displays technical information needed by the driver. In V2I communication it can be a communication channel between vehicle and infrastructure. Through electronic devices paired with Bluetooth it can measure the pedestrian flow in V2I by detecting anonymous Bluetooth signals.

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  1. Wireless Fidelity or Wi-Fi – It can support only infotainment applications in the vehicle. Only the IEEE 802.11p WAVE (DSRC) is capable for safe and reliable communications in V2X applications.
  1. Mobile Network- It is strictly used in transmitting the information from the vehicle to the infrastructure. The Model Deployment is also evaluating the use of existing 3G/4G cellular networks to provide vehicles with updated security certificates.
  2. Short Range Radio- It is an older technology that is widespread in case of vehicles. They work on a lower ISM bandwidth (i.e. 433 or 866 mHz) and broadcasts an identifier which can be received by the traffic control systems prioritising public transport at intersection or stops.

Applications of V2I

Source: EE Herald
  1. Red Light Violation Warning- Based on the speed of the vehicle and distances to intersection this technology alerts the driver of an upcoming red light.
  2. Curve speed Warning- If the speed of the driver is more than the ideal speed on an upcoming road curve, this technology will alert the driver to slow down.
  3. Stop Sign Gap Assist- If the intersection is stop sign controlled then due to vehicle gap detection this technology will assist the motorists as to when it is unsafe to enter the intersection.
  4. Reduced Speed Zone Warning- This technology will assist drivers in work zones, by issuing alerts to drivers to reduce speed, change lanes, and/or prepare to stop.
  5. Spot Weather Information Warning- This technology informs the driver about the weather details from various locations.
  6. Stop Sign Violation Warning- This technology alerts the driver in case of violation of stop sign based on vehicle speed and distances to intersections.
  7. Railroad Crossing Violation Warning- It alerts the drivers about the safety of crossing railroad tracks via RSE connections
  8. Oversize Vehicle Warning- Drivers of oversized vehicles will receive an in-vehicle alert to take an alternate route or a warning to stop, based upon information from RSE connections to infrastructure at bridges/tunnels.
  9. Dynamic Traffic Light Control- Based on the type of car such as ambulance, fire brigade or police control car with V2I interaction it can change the traffic light.
  10. Payment and Information- At toll booths or parking lots where number plate is a base for payment applications this technology can be of a lot of help.


 “To get the full benefit of connected and automated vehicles, you need the infrastructure outfitted. Infrastructure can carry and share information about crashes, traffic jams, sharp curves, and with recommended speeds. You can also dynamically change recommended speed based on weather or other conditions.”

-James Sayer,

University of Michigan Transportation Research Institute

With the industry getting more digitalised there is always a risk of invasion of privacy. The credibility and the authenticity of data can also be questioned if the system has some bugs. The vehicles are communicating so that almost eliminates the chances of human error. There are over 10 million people who die every year due to road accidents. This is surely a stepping stone towards ensuring the safety of life and preventing numerous dangerous mishaps in future.

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This article was written by Aditya  and Eeshan for any correction or guest article mail us at


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