An acoustic signature is a set of characteristics used to describe a sound signal which is being observed.
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The acoustic signature may present itself in a gas, liquid or solid medium; furthermore, its temporal nature may be of a repeating waveform, be intermittent, or manifest as a single burst.
The signature may arrive directly from an emission source, or may include sound echos from targets, radiated and ambient noise, with salient echo characteristics including target strength, spectral reflectivity versus frequency, doppler shift, doppler spread and target range extent.
Characteristics of the signature
The acoustical signature generally may be characterized by its:
Energy content or amplitude
Frequency spectrum content
Intermittence or continuity
Directional vector of the transmission
Presence or absence of echoes
There are countless applications of an acoustical signature, some of the prominent ones being:
Voice recognition (identification of a specific person or animal producing an acoustic signature)
Prey location of certain marine mammals or other aquatic fauna (echolocation using prey backscatter)
Military intercept systems (passive monitoring of missile launches, telemetry communications, etc.)
- C.S.Clay and H.Medwin. 1977. Acoustical Oceanography. Wiley, New York
- National Research Council of the National Academies (U.S.) 2003. Ocean Noise and Marine Mammals. The National Academies Press, Washington DC
- D.Simmonds and J.MacLennan. 2005. Fisheries Acoustics: Theory and Practice, 2nd edition. Blackwell, Oxford.
- Noise pollution
- Physical Oceanography Index