Patent ID: 6252521
Filing Date: 2001-06-26
Classification: G08G

Abstract:
An emergency vehicle alert system for use with a number of emergency response vehicles and a number of civilian vehicles, said emergency vehicle alert system comprising:a number of emergency vehicle constant signal strength transmitter units, each installable in one of the number of emergency response vehicles; anda number of signal receiving units, each installable in one of the number of civilian vehicles;each of the emergency vehicle constant signal strength transmitter units including a radio transmitter having an activation switch for allowing an operator to activate the radio transmitter when responding to an emergency;each of the radio transmitters transmitting an emergency vehicle approaching radio signal at a predetermined set radio frequency, in all directions and at a constant signal strength equal to the signal strength of the emergency vehicle approaching radio signal transmitted by said radio transmitter of every other said emergency vehicle constant signal strength transmitter unit and at the same predetermined set radio frequency;each of said signal receiving units including a radio receiver circuit tuned to the predetermined set radio frequency of the emergency vehicle constant signal strength transmitter units and a signal strength detecting circuit having a signal strength detector input in connection with a receiver output of the radio receiver circuit, a variable speaker power output in connection with the variable output speaker and a variable LED power output in connection with the variable output LED light system;the signal strength detector circuit supplying power to the variable speaker power output and the variable LED power output at levels directly proportional to the strength of the received emergency vehicle approaching radio signal such that, as the distance between the transmitter unit and the receiver unit decreases, power to the variable speaker power output and the variable LED power output increases causing the variable speaker output to become louder and more LED's to illuminate and as the distance between the transmitter unit and the receiver unit increases, power to the variable speaker power output and the variable LED power output decreases causing the variable speaker output to lessen in volume and fewer LED's to illuminate, thereby, providing dual mechanisms for allowing a driver of a civilian vehicle to gauge the distance between an emergency vehicle and a civilian vehicle driven by the driver.