Patent ID: 7236101

Claim:
A method of communicating a warning signal comprising: mounting a transmitter and a receiver to an emergency vehicle that outputs a digital signal at periodic intervals that is detectable within a range; said transmitter turning off its own signal at periodic intervals for 3-5 seconds to allow receipt by said receiver of a signal from other emergency vehicles in the vicinity; mounting an additional receiver in a private or commercial motor vehicle that responds to the digital signal from the transmitter of a transmitting emergency vehicle to detect said digital signal; transmitting a digital signal from the transmitter when an emergency vehicle light bar but not a siren of said emergency vehicle is actuated; and displaying a visual warning from a visual indicator mounted to the private or commercial motor vehicle or other emergency vehicle in response by a receiver of receipt of the digital signal from an emergency vehicle transmitter to warn a motorist in the private or commercial vehicle and/or an other emergency vehicle of a presence of the emergency vehicle whose light bar has been actuated is within said range.