Our traffic signals use a variety of control methods based on the conditions of a particular corridor.  One way streets with intersections in close proximity are optimal for this type of operation.  For example, in the downtown core we have coordinated the signals to provide clean progressions along the one ways on 99 and 100 avenues.  Coordination in two way situations is used to minimize overall delay for vehicles, but does not provide the obvious “green wave” that most people expect.

These cameras are detectors.  When a vehicle pulls up to the stop bar opposite the camera, a call is placed to the computer that controls the intersection.  The intersection will then service that movement at the next available opportunity.  These cameras can also be used to count traffic, and to extend green lights based on demand.  These cameras do not record any information and lack the resolution to identify particular people or vehicles.

Yes, but only for fire vehicles.  When a fire department vehicle is responding to a call with lights and sirens engaged, it communicates to the nearest intersection with its location and direction.  The signals will then give a green to only that direction until the vehicle has passed.  It then returns to normal operation.

The length of a yellow light is primarily based on the speed of the approach.  There is a minimum of 3.0s which increases as the speed limit of the road increases.  In some situations this may be increased due to environmental factors such as compromised sight lines, curves in the approach, etc..

When you hit a pedestrian button, a request for service is sent to the computer that controls the intersection, much like when a vehicle pulls up to the stop bar.  The intersection continues its sequence as normal and then activates the walk signal when its corresponding vehicular movement is initiated.  The amount of time that you have to wait is purely based on where in the cycle the button is pushed.