Two-Way Bandwidth Maximization Model with Proration Impact Factor for Unbalanced Bandwidth Demands

Abstract

Progression bandwidth maximization is one of the most important signal coordination strategies for urban arterial signal control. MAXBAND and MULTIBAND have implemented a weighting factor that is capable of adjusting the bandwidth according to unbalanced bandwidth demands in a two-way bandwidth maximization problem. The maximum bandwidth solution may not be achieved with certain values of weighting factors; therefore, users may need to have a well-developed idea about what weighting factor to use in order to not compromise the total bandwidth. In this paper, we propose a new two-way bandwidth maximization model that not only maximizes the total bandwidth, but also introduces a bandwidth proration impact factor. This impact factor allows the user to control the importance of satisfying the target bandwidth demand ratio. Numerical examples have demonstrated that the new model has the following advantages: (1) when two-way progression solution is not physically possible, the model first guarantees maximum total bandwidths and then automatically prorates the bandwidth fully to the direction with higher traffic demand; (2) when two-way progressions can be achieved, the model not only guarantees maximum total bandwidth but also automatically prorates the bandwidth in a ratio as close as possible to the ratio of bandwidth demands.