Underwater Acoustic Transducers Information
Underwater acoustic transducers can contain both transmitters and receivers, or they can be solely transmitters used in conjunction with a hydrophone. They sense reflected sound and use distance and directional data for communication, mapping and navigation. Underwater acoustic transducers have an operational range, but are usually designed to operate at their resonance frequency to maximize output power. They are most typically single frequency transmitters, but they may contain multiple transmitters and receivers for different frequencies.
The most critical performance specifications for underwater acoustic transducers are sensitivities, power capability and pressure and depth ratings. The transmit sensitivity is the ratio of sound pressure produced to the input voltage. Receive sensitivity is the ratio of output voltage produced over sound pressure sensed. Power capability is the signal power available from the transducers. A maximum pressure rating may be specified, indicating how much pressure the transducers can have applied to them and still function properly. The transducers will likely also have a maximum depth specification, again indicating how deep they can be submerged and still function as they are supposed to. These maximum depth and pressure ratings are distinct from survivability specifications, which would indicate the maximum environmental characteristics the transducers can withstand before becoming inoperable.
Many features for underwater acoustic transducers are available. These devices can be horizontally omnidirectional, having a beam pattern that is virtually equal in all horizontal directions. They can have multiple frequencies and be usable at an unlimited ocean depth. Sidescan transducers are designed for a focused directional beam pattern to the side. Underwater acoustic transducers are often available as an array, several transducers arranged together as a system.