Application of NTCIP Standard 1211 Framework for Upgrading Downtown Baltimore Light Rail Transit Signal Priority

摘要

The Maryland Transit Administration, in collaboration with the city of Baltimore, has developed a concept of operations for light rail transit (LRT) signal priority along the Howard Street corridor in Baltimore, Maryland. The National Transportation Communications for ITS Protocol (NTCIP) 1211 standard was relied upon heavily by the project team to provide a framework to describe the functional requirements for the priority system. The project team analyzed the existing system and its limitations to determine changes that would be needed to implement signal control priority in a fashion that was amenable to both the transit agency and the city traffic engineer. The result will be a priority control system that provides time savings for LRT vehicles while maintaining coordination of traffic signals in order to prevent congestion caused by more disruptive traffic signal preemption. The importance of the NTCIP 1211 standard is that it defines priority as an operational concept that provides preferential service for selected vehicles based upon agreed criteria while not losing coordination. This type of operation meets the objective of providing signal timing that is transit friendly without degrading service to other vehicles to a level that causes disruption to the overall operation of the system. Baltimore's Howard Street LRT corridor will be used as a case study to demonstrate the benefits of NTCIP 1211 on transit and street operations.