Sonar
Sonar (SONAR, Sound navigation and ranging, Sonar) is a device that searches, detects, and ranges waterborne vessels, submarines, objects underwater and sea floor, using sound waves propagating in the water. It is also called an ultrasonic probe. It is a combination of a sound wave transmitting device and a hearing device for underwater measurement, and it refers to the entire detection system centered on a vibrator and a detector. Normally, ultrasonic waves are used, sound waves are emitted, and distance and direction are detected by reflection from an object, but there are types that detect and measure sounds emitted by objects underwater, not reflections. As a military item, from a complex large-scale underwater device combining modes that emit sound waves themselves or modes that only listen without themselves generating sound waves, to simple fish finder including leisure, various sonars Exist. It is also used to measure water depth, there are Doppler / sonar that measures the ship's sailing speed. ...