Techniques for this include the use of comb transducers, wedges, waves from liquid media and electro magnetic acoustic transducers ( EMAT's ).
12.
This pulse of sound is generally created electronically using a sonar projector consisting of a signal generator, power amplifier and electro-acoustic transducer / array.
13.
The phased array principle is also used in acoustics, and phased arrays of acoustic transducers are used in medical ultrasound imaging scanners and military sonar systems.
14.
Electromagnetic acoustic transducers ( EMAT ) induce ultrasonic waves into uniformly-milled metal inspection objects ( e . g ., pipe walls, tank floors ).
15.
Some multibeam echosounders such as the Teledyne Odom ES3 also incorporate a motion sensor at the face of the acoustic transducer, allowing even faster installation on small vessels.
16.
Electromagnetic Acoustic Transducer "'( "'EMAT "') is a transducer for non-contact sound generation and reception using electromagnetic mechanisms.
17.
Secondly, the speed of sound may be directly measured using a small acoustic transducer and a reflecting surface, mounted at a known distance from the acoustic center of the transducer.
18.
An electromagnetic acoustic transducer ( EMAT ), is a type of non-contact ultrasound that generates an ultrasonic pulse which reflects off the sample and induces an electric current in the receiver.
19.
In the case of the TARGT GIB, the GPS and RF antennas are located on top of the sensor and the hydrophone, or underwater acoustic transducer, is located on the bottom.
20.
The concepts of main lobe and sidelobes also apply to acoustics and optics, and are used to describe the radiation pattern of optical systems like telescopes, and acoustic transducers like microphones and loudspeakers.