Traffic Phase means traffic signals of each direction during a specific time period display a combination of different colors.
Normally for a 4-way intersection, a completely signal time cycle can be divided into 4 traffic phases.
Type 1)
Phase A: East-West movement, including main road movement, right turn, and pedestrian.
Phase B: East-West movement, only left turn.
Phase C: North-South movement, including main road movement, right turn, and pedestrian.
Phase D: North-South movement, only left turn.
Type 2)
Phase A: East movement, including main road movement, right turn, left turn, and North pedestrian.
Phase B: North movement, including main road movement, right turn, left turn, and Western pedestrian.
Phase C: Western movement, including main road movement, right turn, left turn, and South pedestrian.
Phase D: South movement, including main road movement, right turn, left turn, and East pedestrian.
Principle of setting traffic phase
For our traffic controller, clients could set up the traffic phase such as time, sequence, etc. according to the project needs.
In addition, in order to clear the vehicle in the previous phase, normally green light of the new traffic phase will turn on after 2 seconds following the red light of the previous traffic phase. The setting of the intersection signal phase needs to be considered according to the specific situation of each intersection. In general, reducing the phase quantity will be helping to reduce traffic waiting time. However, when if there is a traffic conflict in one phase, it has to be divided into different phases and assign a reasonable green signal time.