The process of locating objects by emitting sounds and interpreting the reflected sound waves is?

Echolocation

Explanation:

Echolocation is the act of emitting sounds to the environment and listening to the echo of the emitted sound. Various animals use it like bats, shrew, swiftlets etc.

The same concept is used in active sonar where it is used underwater to detect the depth and objects. The time it takes for the wave to be reflected back gives a rough estimation of the depth.