How is cycle length defined in traffic signal operations?

Cycle length in traffic signal operations is defined as the duration from the start of a display until that same display occurs again. This encompasses the entire sequence of phases a traffic signal goes through, including green, yellow, and red phases for all conflicting movements, until the initial phase is repeated.

This definition emphasizes that a cycle consists of all sequences in which traffic signals alternate, ensuring all vehicles and pedestrians get their opportunities to proceed safely. It reflects not just the time taken for any single phase but the cumulative duration from the beginning of one complete phase until that phase returns to its starting point.

On the other hand, the total duration of one complete cycle, mentioned in the first choice, is a broader way to phrase the definition but does not clearly capture the essence of "display” and its repetition, which are vital. The maximum duration of a green signal and the average time between phases switching refer to specific components or aspects of the traffic signal operation, rather than the comprehensive and cyclical nature defined as cycle length.