Roadway systems and methods for conditionally transmitting a radio signal to vehicles, depending on whether a certain person is in the area

摘要

Disclosed are alert systems and methods for a roadway. According to one exemplary method, there is a step of receiving an identification signal from a device carried by a human having a medical condition. Subsequently, circuitry acts to conditionally cause a changeable road sign to display the medical condition, and conditionally transmit a radio warning signal to a vehicle, the radio warning signal indicating the medical condition.