sonar pulse transmission; pinging
Technical term used in sonar and underwater acoustics; refers to sending out a sound pulse and listening for echoes.
The submarine emits a sonar pulse to survey the surrounding situation.
By pinging, one can investigate the topography of the seabed.
active sonar
Compound of 探 (search, probe) and 信 (signal, message), likely coined in technical contexts for sonar pulse transmission.