Maxband

Maxband is a traffic signal timing optimization technique used to coordinate signals along arterial road corridors in order to create a green wave for vehicles traveling at a chosen speed. The method aims to align signal offsets and cycle lengths so that a progressing vehicle encounters successive green phases across multiple intersections, improving throughput and reducing stops and delays.

The core idea of Maxband is to optimize timing parameters—primarily cycle length, signal offsets, and green splits—subject to constraints such as minimum and maximum green times, lost time, and safety requirements. The objective is to maximize the width of a progression band, or to maximize the number of signals that can be traversed while remaining within a green window, across the corridor. In practice, the problem is formulated as a linear programming model that computes a common cycle length for the signals and the relative offsets needed between adjacent intersections to achieve coordinated progression.

Maxband is often paired with related methods, such as SIGBAND, which extend the approach to handle multiple progression bands, varying speeds, or more complex network geometries. The technique assumes relatively stable conditions and consistent speeds along the corridor, and it typically applies to homogeneous trips along a primary route. Limitations include sensitivity to traffic demand fluctuations, turning movements, pedestrian phases, and deviations from assumed speeds, which can reduce the effectiveness of the planned progression.

Today, Maxband remains a foundational concept in traffic engineering for arterial coordination, frequently taught in transportation curricula and used as a basis for more advanced signal optimization tools.