Which instrument uses ultrasonic waves to measure the distance, direction and speed of under water objects?

The instrument that uses ultrasonic waves to measure the distance, direction, and speed of underwater objects is called a "sonar" (Sound Navigation And Ranging). Sonar systems emit pulses of high-frequency sound waves into the water, and then they listen for echoes reflected back from objects in the water. By analysing the time it takes for the sound waves to travel to the object and return, sonar systems can calculate the distance to the object. Additionally, the direction and speed of the object can be determined by analysing changes in the frequency and phase of the returning echoes. Sonar technology is widely used in various applications such as navigation, underwater mapping, fishing, and military purposes.