Smart Intersections & Connected Streets: The World Around AVs

Autonomous vehicles don't operate in isolation. They move through a world of traffic lights, signs, crosswalks, and — increasingly — connected infrastructure.

Let's look at how smarter streets can work alongside AVs.

What is V2X?

You might see the term V2X — short for Vehicle-to-Everything communication.

It's an umbrella for:

• V2I – Vehicle-to-Infrastructure: Cars talking to traffic lights, signs, or roadside units.
• V2V – Vehicle-to-Vehicle: Cars sharing information with each other.
• V2P – Vehicle-to-Pedestrian: Alerts between vehicles and people's devices (like smartphones).

These systems typically use wireless messages to broadcast things like:

• "This light will turn red in 5 seconds."
• "There is a vehicle stopped ahead beyond your line of sight."
• "Emergency vehicle approaching."

Smart intersections in practice

A smart intersection might have:

• Connected traffic signals that share their timing plans
• Sensors or cameras detecting pedestrians and cyclists
• Roadside units broadcasting information to vehicles

For AVs and connected vehicles, this can provide:

• Earlier warnings about red lights or phase changes
• Visibility into occluded areas (e.g., a hidden pedestrian about to cross)
• Better coordination, reducing sudden stops and wasted time

Do AVs need smart infrastructure?

Most AVs are designed to operate using only their own sensors and maps. That's important:

• They must still drive safely if a connection drops.
• They can't depend on every intersection being upgraded.

However, connected infrastructure can enhance performance, especially in tricky scenarios:

• Complex intersections with limited visibility
• High-speed corridors where early warnings help smooth traffic
• Priority lanes for transit or emergency vehicles

Think of it this way:

AVs are designed to be self-sufficient, but connected streets can make the whole system smoother and safer.

Benefits beyond AVs

The good news: smart infrastructure doesn't just help autonomous vehicles.

It can also:

• Improve bus reliability with signal priority
• Give cyclists safer crossings with better detection
• Provide better data to city planners about how streets are used
• Enhance safety for human drivers via in-car alerts

In other words, investing in smarter streets can pay off even before AVs are widespread.

The road ahead

Fully connected cities won't appear overnight. But you'll likely see:

• More pilot projects at key intersections
• Specific corridors where transit and AVs benefit from priority and coordination
• Gradual standards around how vehicles and infrastructure talk to each other

As this evolves, AVs will be one of the biggest beneficiaries — but not the only ones.