An Enhanced Cell Transmission Model for Traffic Operations within a Signalized Intersection

This paper presents an enhanced cell transmission model (CTM) to capture the operation of traffic within a signalized intersection at the microscopic level. Different from previous studies that focus on traffic dynamics on links at the intersection, this study contributes to modeling the traffic operations within the intersection. More specifically, different types of virtual cells are proposed to simulate interactions of traffic movements in details, such as the approach diverging, the exit merging, and the conflicts between the left turn and the opposing through if the intersection is controlled by a two-phase signal. In addition, approaches and exits of the intersection are divided into two-dimensional cells according to lane widths. The state of a cell indicating its blockage or not is proposed to capture operational performance of the intersection. Numerical results show that the proposed model can capture the operation of traffic at a signalized intersection with high level of accuracy and computational efficiency for both under-saturated and oversaturated conditions, indicating its potential to be used in signal optimization.