Traffic signal systems represent a substantial component of the highway transportation network in the United States. It is challenging for most agencies to find engineering resources to properly update signal policies and timing plans to accommodate changing traffic demands. Upgrading existing systems can achieve incremental benefits, but do not address the fundamental problem that information about system performance is not communicated to the agency in a meaningful or systematic way. This project developed a collaborative pilot deployment partnership between a large public agency, university, and commercial equipment manufacturers to define an architecture for a centralized traffic signal management system that can be used on a large geographic scale by both maintenance and technical services staff. This architecture leverages wireless IP communications to integrate performance measures into a database environment and a performance measure dashboard.

In addition to this architecture, several uses of high resolution signal controller event data are presented. An extended discussion of a visualization technique called the “Purdue Coordination Diagram” is presented, which enables new methods for visualizing and assessing 24-hour corridor operations without field visits or searching through hours of recorded video. A new methodology for using data from peer intersections to estimate fundamental traffic flow characteristics is proposed. In this methodology, phase status from an upstream intersection is fused with downstream detector status to obtain link travel time and platoon dispersion characteristics. Finally, this data is integrated into an optimization engine for determining cycle length, phase sequence, and offsets.

Report Number



traffic signal systems, traffic signal optimization, performance measures, traffic signal timing, traffic signal architecture, SPR-3409

SPR Number


Performing Organization

Joint Transportation Research Program

Publisher Place

West Lafayette, Indiana

Date of this Version


Appendix_B.pdf (783 kB)
Appendix B: Data Reduction Procedures for Traffic Signal Systems Performance Measures

Appendix_F.pdf (978 kB)
Appendix F: Optimization of Offsets and Cycle Length Using High Resolution Signal Event Data

3409_technical_summary.pdf (1050 kB)
Technical Summary