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Stakeholder Invitation: Connected Signalized Intersection Standard Project

The U.S. DOT ITS Joint Programs Office has initiated a new project, Connected Signalized Intersection standard, for which stakeholders representing public and private sectors as well as individuals, are invited to participate. The intent of the project is to have a balanced list of stakeholders representing infrastructure, automotive sector, and smart mobility, to ensure consistency and interoperability while receiving timely input from the industries mentioned.

The project purpose is to develop and publish a Connected Signalized Intersection document that addresses the ambiguities and gaps identified by early deployers. This project ensures that future deployments are interoperable across the United States, especially for automated transportation systems. The first version of this standard focuses on harmonizing existing SPAT, using the USDOT-sponsored Cooperative Automated Transportation Clarifications for Consistent Implementations (CCIs) To Ensure National Interoperability Connected Signalized Intersections as a starting point.

For this project, a connected signalized intersection is defined as an infrastructure system that broadcasts signal, phase and timing (SPaT), mapping information, and position correction data to vehicles. Following the Systems Engineering Process (SEP), project development will include a Concept of Operations (ConOps), System Requirements (SyRS or Functional Requirements), System Design Details, and associated SEP walkthroughs, as well as a software Reference Implementation.

The project will result in either a Standard or ‘Recommended Practice (RP)’ (or similar work, such as best practices) that demonstrates consensus via three associations’ standards development processes. The project will consider based on input from the Connected Signalized Intersection Committee and stakeholders, standardizing key capabilities expected in a Connected Signalized Intersection, as well as a software Reference Implementation (RI).

This proposed standard or RP incorporates relevant user needs, requirements and design elements of the RSUs defined in the RSU Specification 4.1, and NTCIP 1218 Object Definitions for RSUs, as well as relevant automobile standards and interfaces as applicable. The project team validates it through outreach to the real-world RSU deployments such as the Connected Vehicle (CV) Pilots programs, and the Signal Phase, and Timing (SPaT) Challenge.

Following the SEP, project development will include a Concept of Operations (ConOps), System Requirements (SyRS or Functional Requirements), System Design Details, and associated SEP walkthroughs, as well as a hardware and application software reference implementation. The project will result in a standard that demonstrates consensus standards development processes.

Stakeholders should anticipate that up to 15 web-enabled conference calls and three face-to-face meetings within the United States are to be held during the life of the project.

Stakeholders: Stakeholders with an interest/expertise in the following areas are invited to participate:

  • Participants in automated vehicle software development, as well as RSU deployments, and Connected Vehicle Pilots and the Signal Phase and Timing (SPaT) Challenge.
  • Transportation Infrastructure (including RSU) hardware and/or software design, manufacture, integration, operation (since infrastructure is expected to communicate).
  • Vehicle communication hardware and/or software design (including automated and fleet vehicles), manufacture, integration, and operation (since vehicles and connected signalized intersections are expected to communicate)
  • Software and/or hardware design manufacture, integration, and operation for pedestrian and other vulnerable road users (since pedestrians and other VRUs are expected to communicate)

The associations actively participating in this effort are the Society of Automobile Engineers (SAE), American Association of State Highway Transportation Officials (AASHTO), National Electrical Manufacturers Associations (NEMA), and Institute of Transportation Engineers (ITE).

To participate in the Connected Signalized Intersection Standard Committee, please email us at Subject line/Attention to: Connected Signalized Intersection

Project progress and updates can be found here: