Acoustic homing

Acoustic homing is a system which uses the acoustic signature (sound) of a target to guide a moving object, such as a torpedo. Acoustic homing can be either Passive or Active in nature. Using Passive, the system is designed to move either toward or away from a sound, and may also be designed to move only toward certain types of sounds to the exclusion of others, while Active is a true Sonar. The system emits a sound pulse that reflects off objects and then back to the system, where the system processes the echos to determine the proper response.