A sonar beam is essentially a pulse of sound waves emitted by a sonar device, used to explore underwater environments.
Think of a sonar beam as a highly focused "ping" or pulse of sound sent out into the water. This sound wave travels through the water until it encounters an object or the seabed.
How a Sonar Beam Works
Based on the provided reference:
- Cone of Sound: Much like a flashlight beam, the emitted sound pulse, often called a "ping," expands the deeper it travels, which forms a cone of emitted sound. This conical shape broadens the area covered by the sonar as the distance increases.
- Interaction with Objects: When the ping hits any object with a density or sound speed different from the surrounding water, such as fish, shipwrecks, or the bottom itself, the ping will bounce off of it. These returning sound waves are called echoes.
- Returning Echoes: The bounced-off sound, or echo, then return[s] to the split-beam transducer (the part of the sonar that sends and receives the sound). By measuring the time it takes for the echo to return and the strength of the signal, sonar systems can determine the location, size, and even composition of the object.
Key Characteristics:
- Emitted sound pulse (ping).
- Travels underwater.
- Expands into a cone shape with depth.
- Bounces off objects (echoes).
- Used for detection and mapping.
In essence, the sonar beam is the fundamental tool sonar uses to "see" underwater by sending out sound and listening for the reflections.
