Simrad ES80 - Acoustic Noise; Contributing Factors

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Acousticnoise
Aswithanyotherhydroacousticsystems,thequalityoftheES80echodataand
presentationsaresubjecttounwantedacousticnoise.Theechoesfromanylargeand
smalltargetmustbedetectedinsidethenoise.
Topics
Contributingfactors,page462
Selfnoise,page464
Ambientnoise,page466
Fishinggearnoise,page467
Electricalselfnoise,page467
Somemeanstoreduceacousticnoise,page467
Contributingfactors
Severalfactorsarecontributingtotheperformanceofthehydroacousticequipment
usedonboardavessel.
Factorscontributingtotheperformanceofthehydroacousticequipmentusedonboarda
vesselare:
•Thequalityandpropertiesofthetransmittedsignal
•Thequalityofthereceivingsystem
•Theoperationalsettingsmadeduringoperation
•Thepropertiesofthetarget(s)
•Thesignal-to-noiseratio
Themajorityofthesefactorscanneitherbecontrollednorimprovedbymeans
ofinstallationmethodsortransducerlocations.Thequalityandpropertiesofthe
transmittingandreceivingsystemsarekeyfactorsduringourproductdevelopment,while
ourenduserdocumentationaimstohelptheusertomaketherightltersettingsduring
operation.Asforthetargetproperties,thereisnothinganyofuscandowiththose.
Thesignal-to-noiseratio,however,canbeimprovedbymakingthecorrectchoices
duringinstallation.
Signal-to-noiseratio(oftenabbreviatedSNRorS/N)isameasureusedin
scienceandengineeringthatcomparesthelevelofadesiredsignaltothelevelof
backgroundnoise.Itisdenedastheratioofsignalpowertothenoisepower,often
expressedindecibels.Aratiohigherthan1:1(greaterthan0dB)indicatesmore
signalthannoise.WhileSNRiscommonlyquotedforelectricalsignals,itcan
beappliedtoanyformofsignal[...].
SimradES80ReferenceManual