17.3Traditionalsonartechnology
Traditionalsoundersuseasinglecarrierfrequencyorcarrier
waveforthesonarping.Thesesoundersworkbymeasuring
thetimeittakesthepingechotoreturntothetransducerto
determinetargetdepth.Usingthismethodif2targetsareclose
togethertheycanbeshownasasinglelargetarget,ratherthan
multiplesmallertargets
17.4BroadbandCHIRPsonar
technology
Broadbandsonarsuseasweptfrequency'CHIRP'signalwhich
candistinguishbetweenmultipleclosetargets,thisenables
thesonartodisplaymultipletargetsinsteadoflargecombined
targets.
Someofthebenetsareimproved:
•T argetresolution.
•Bottomdetectioneventhroughbaitballsandthermoclines.
•Detectionsensitivity.