Camera's at intersections around Pima County???

So I'm wondering what these are? They started appearing around the northwest side of town in Pima County about a year ago. There is only one at each intersection. I'm assuming they are cameras... but what for?

This is at Romero and Wetmore.



This is at Romero and Ruthrauff.



This is at Wetmore and Flowing Wells.



This is at La Canada (/Flowing Wells) and River (notice how the set of antennas are on a different poll as the "device").



These aren't to be confused with...

What I believe is the device that changes the light for emergency vehicles (and the obvious strobe light).



What I believe is a camera/device that senses when traffic is at the intersection so it can change the light accordingly (these are not at all intersections/directions, because some intersections have a loop in the pavement or the light has a predominate flow in one direction.

Any clues? Post here... Camera's at intersections around Pima County??? - These are not red light or speeding cameras as far as I know