Search results
Results from the WOW.Com Content Network
The SOFAR channel (short for sound fixing and ranging channel), or deep sound channel (DSC), [1] is a horizontal layer of water in the ocean at which depth the speed of sound is at its minimum. The SOFAR channel acts as a waveguide for sound, and low frequency sound waves within the channel may travel thousands of miles before dissipating.
If the speed of sound in water is known for the full water column profile, the depth and position of the return signal can be determined from the receive angle and the two-way travel time. In order to determine the transmit and receive angle of each beam, a multibeam echosounder requires accurate measurement of the motion of the sonar relative ...
Output of a computer model of underwater acoustic propagation in a simplified ocean environment. A seafloor map produced by multibeam sonar. Underwater acoustics (also known as hydroacoustics) is the study of the propagation of sound in water and the interaction of the mechanical waves that constitute sound with the water, its contents and its boundaries.
Underwater communication is difficult due to factors such as multi-path propagation, time variations of the channel, small available bandwidth and strong signal attenuation, especially over long ranges. Compared to terrestrial communication, underwater communication has low data rates because it uses acoustic waves instead of electromagnetic waves.
Geometrical acoustics or ray acoustics is a branch of acoustics that studies propagation of sound on the basis of the concept of acoustic rays, defined as lines along which the acoustic energy is transported. [1] This concept is similar to geometrical optics, or ray optics, that studies light propagation in terms of optical rays.
Direct-field acoustic testing, or DFAT®, is a technique used for acoustic testing of aerospace structures by subjecting them to sound waves created by an array of acoustic drivers. [1] The method uses electro-dynamic acoustic loudspeakers, arranged around the test article to provide a uniform, well-controlled, direct sound field at the surface ...
The theory of sound wave propagation is very similar mathematically to that of electromagnetic waves, so techniques from transmission line theory are also used to build structures to conduct acoustic waves; and these are called acoustic transmission lines.
Swedish soldiers operating an acoustic locator in 1940. Acoustic location is a method of determining the position of an object or sound source by using sound waves. Location can take place in gases (such as the atmosphere), liquids (such as water), and in solids (such as in the earth).