Target strength

Sonar image of the wreck of USS O-9.

The target strength or acoustic size is a measure of the area of a sonar target. This is usually quantified as a number of decibels. For fish such as salmon, the target size varies with the length of the fish and a 5 cm fish could have a target strength of about -50 dB.^[1]

Target strength (TS) is equal to 10 log₁₀(σ_bs/(1 m²)) dB, where σ_bs is the differential backscattering cross section. Backscattering cross section is 4πσ_bs.

References

↑ J.E. Ehrenberg (1989), "A review of target estimation techniques", Underwater Acoustic Data Processing, Springer, ISBN 9780792301271

"Introduction to the use of sonar systems for estimating fish biomass, FAO Fisheries Technical Paper No. 191, Revision 1, FAO 1982"
Fisheries Acoustics Simmonds, E John and MacLennan, David N (2005) Blackwell Publishing. ISBN 978-0-632-05994-2
C. S. Clay & H. Medwin, Acoustical Oceanography (Wiley, New York, 1977)

target strength formula:

e.g. for a sphere with radius $r$ :

TS $=10\log(r^{2}/(4$ m $^{2}))$ dB

This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.

[1] J.E. Ehrenberg (1989), "A review of target estimation techniques", Underwater Acoustic Data Processing, Springer, ISBN 9780792301271

[1]

References

Further reading