GPS is already beacon infrastructure that tells cars where they are on the streets :)
It cleverly got around our allergy to spending on infrastructure by being cold-war-era military technology.
It cleverly got around our allergy to spending on infrastructure by being cold-war-era military technology.
Yeah, but it doesn't say where the streets are, or where the traffic lights are, or (officially) what's the speed limit on this stretch of road, etc. All those are via the layer that's applied by a private company, and may differ substantially from how the city itself intends to direct traffic.
I used to work for TomTom and at the time they were just getting into the self-driving cars sector. I don't know where they are with it now, but four years ago they were already building high-definition 3D maps for autonomous cars. And they had road sign reading technology.
You can see their HD 3D map in a video [1] where they also explain how it's constructed using their mapping vehicles.
EDIT: To make my point clear, we don't really need to invest in smart roads - the cars and the supporting tech are already smart enough.