Train anticollision system on basis of sound wave warning and anticollision method thereof

The invention relates to a train anticollision system on the basis of the sound wave warning and an anticollision method thereof, relates to the technical field of the rail transit and solves the technical problem of improving the safety of a train in a tunnel. The system comprises a plurality of sound wave warning units which are respectively arranged on each train; each sound wave warning unit comprises a sound wave receiving device arranged on a locomotive of the corresponding train, a sound wave transmitting device arranged on a tail of the corresponding train and signal control processing equipment; and a previous train transmits a sound wave warning signal consisting of sound waves with at least one frequency or frequency band to a next train and the next train receives the sound wave warning signal transmitted by the previous train and then estimates the distance between the previous train and the next train according to the attenuation and dispersion characteristics of the sound wave warning signal and timely carries out early warning. The system and the method which are provided by the invention are particularly suitable to apply in the urban subway line.