Raymarine A series - Sonar Technologies Explained

19.2Sonartechnologies
Traditionalsonartechnology
Traditionalsonarusesasinglecarrierfrequencyor
carrierwaveforthesonarping.Thesonarworksby
measuringthetimeittakesthepingechotoreturnto
thetransducertodeterminetargetdepth.
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CHIRPtechnology
CHIRPsonarsuseasweptfrequency'CHIRP'signal
whichcandistinguishbetweenmultipleclosetargets,
thisenablesthesonartodisplaymultipletargets
insteadoflargecombinedtargetsthatyouwouldsee
whenusingtraditionalnon-CHIRPsonar.
BenetsofCHIRPincludeimprovementstotarget
resolution,bottomdetectioneventhroughbaitballs
andthermoclinesanddetectionsensitivity.
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CHIRPSonaroverview
CHIRPsonarproducesaconicalshapedbeam,the
coverageoftheconicalbeamisthewatercolumn
directlybeneaththevessel
Conicalbeam
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Sonariseffectiveatarangeofspeeds.Indeeper
waterstheCHIRPbandwidthisautomatically
optimizedtoimprovebottomlockandthedetection
ofmovingobjects(e.g.sh)inthewiderwater
column.
CHIRPsonarscreenexample
CHIRPDownVision
TM
overview
DownVision
TM
producesawide–angleside-to-side
beamandathinfore-to-aftbeam.Thecoverageof
theDownVision
TM
beamisawatercolumndirectly
beneathandtothesidesofthevessel.
DownVision
TM
beam
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264aSeries/cSeries/eSeries