Perhaps the most well-known branding for these types of devices is called Opticom. Essentially, the tech works by detecting a specific pattern of infrared light emitted by the Mobile Infrared Transmitter (MIRT) installed in a police car, fire truck, or ambulance when the MIRT is switched on.
ATSC systems can reduce vehicle wait time by 40%, cut travel time by nearly 26%, and lessen vehicle emissions by 21%, according to Carnegie Mellon University. Digital traffic signals can dispatch pre-processed and raw data to a connected cloud-based control center, such as an intelligent transport system (ITS).