Traffic signal communication to vehicles

Applying connected vehicle (CV) technologies at signalized intersections can facilitate traffic signal communication with vehicles.

Key characteristics





WSDOT regions

Other names

  • Connected vehicle technologies

Strategy description

At signalized intersections, CV technologies can facilitate communication between traffic signals and vehicles to provide real-time information about signal timing and upcoming signal changes. By equipping vehicles with CV technology, drivers can receive alerts and warnings about approaching signal changes, allowing them to adjust their driving behavior accordingly. This can reduce congestion, improve fuel efficiency, and enhance safety by reducing the likelihood of red-light running and collisions. Additionally, signalized intersections can use CV data to optimize traffic flow and reduce delays.

When to use this strategy

Connected Vehicle (CV) technologies can be applied at signalized intersections to facilitate traffic signal communication with vehicles when there is a need to improve road safety, mobility, and efficiency.


  • Improve pedestrian and bicyclist safety
  • Enhanced situational awareness through vehicle-to-everything applications and enhanced monitoring capabilities
  • Reduce delay of equipped emergency vehicles and transit buses

What you need in order to implement

Planning needs:

  • Before implementing CV technologies at the intersections, agencies should use the systems engineering process to identify needs and requirements

Equipment needs:

  • Vehicle sensors that calculate volumes in each lane
  • Communications equipment between each intersection so the traffic signals can share data
  • Communications equipment connecting the traffic signals to a central server and to the vehicles
  • Common software at each traffic signal

Maintenance needs:

  • CV technologies need regular updating and maintenance

Technical skills need:

  • Agencies must commit resources to apply CV technologies

Learn more about this strategy

About key characteristics

Cost notes:

Costs associated with CV technologies are high as they require construction and technology expenses. The high level of technological sophistication and coordination required means that deploying CV technologies at intersections can be costly and time-consuming, but the potential benefits justify the investment.

Technology notes:

Technology needs associated with the CV technologies are high since it requires a complex and integrated system of hardware, software, and communication protocols to enable real-time communication between vehicles and infrastructure.

Collaboration notes:

Medium levels of collaboration are necessary to develop strategies and policies for CV technologies.