Simrad EK15 - Concepts; Observation Range

SimradEK15
Concepts
Observethefollowingdescriptionsofkeyconcepts.
Topics
•Observationrangeonpage268
•Bottomechoonpage269
•Wavepropagationonpage270
•Biomassonpage271
•Dynamicrangeanddisplaypresentationonpage271
•Bottomslopesonpage272
Observationrange
Absorptionincreasesdramaticallywithfrequencyinsaltwater.Formaximum
observationrangeyoushouldselectalowoperatingfrequency,alargetransducerandthe
maximumtransmitpower.
Typicalobservationrangesareshowninthetable.UsingtheSimradES38Btransducer
(38kHz,7x7degrees,2000W)youcanobservea60centimetercoddownto950meters,
andbottomdetectionworksdownto2800meters.However,withtheSimradES200–7C
transducer(200kHz,7x7degrees,1000W)youcanonlyobservethatsamecoddownto
270meters,andbottomdetectionbecomesunreliablebelow500meters.
Table1Maximumdetectiondepth,singlebeamtransducers
TransducerFrequency
(kHz)
Pulse
duration
(ms)
Bandwidth
(hz)
Txpower
(W)
Rangesh
(m)
Range
bottom(m)
12–161216,4193200085010000
27–26278,18387300011004400
38/200D
384,0976610005002100
38–9384,0976615008002600
38–7384,0976620009502800
50/200D
502,05149310005001500
50–7502,05149320007001900
120–251201,0230261000390800
50/200D
2001,0230881000280550
Table2Maximumdetectiondepth,splitbeamtransducers
TransducerFrequency
(kHz)
Pulse
duration
(ms)
Bandwidth
(hz)
Txpower
(W)
Rangesh
(m)
Range
bottom(m)
ES18–11188,21382200011007000
ES38B384,0976620009502800
268
351718/C