Impact of Origin-Destination Flows on Signal Timing and Performance

There are two common objectives when performing signal timing optimization and deriving coordinated signal timing plans: maximizing bandwidth and/or minimizing delay. It is hypothesized that signal timing solutions would depend on the Origin-Destination (OD) traffic flow patterns. The primary objective of this paper is to investigate how signal system's performance changes under various OD flows and coordinated signal timing plans. A case study was conducted using data collected from a signalized arterial in Reno, Nevada to demonstrate the investigation. VISSIM traffic simulation was used to compare the performance of two signal timing plans under three different OD patterns. The two signal timing plans included a bandwidth-based solution from PASSER II and a delay-based solution from Synchro. The three OD patterns were derived based on the same set of turning volumes. Results from the simulation indicated that different OD patterns produced different performance measures under the same signal timing. It was also found that bandwidth-based signal timing outperformed delay-based signal timing in all the cases analyzed, especially when the arterial traffic was dominant.