Underwater Acoustics

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• Underwater Acoustics
• Developments at NEMO Sites
• SUD
• Acoustics on NEMO Phase 2

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SUD abstract
Following the scientific and technological
success of ONDE, a pilot experimental acoustic
station that acquired and transmitted acoustic
data from 2000 m depth for 2 years, I propose the
realisation of SUD (Sound Underwater Detector) an
innovative deep-sea station for long-term on-line
monitoring of acoustic signals. The innovations
of proposed project are summarised in seven key
items 1) pressure resistance up to 350 bar
(corresponding to 3500 m depth) 2) capability
to operate for more than 5 years 3) capability
to transmit data to shore from distances of about
100 km 4) sensitivity close to Wenz minimum
noise and dynamic range of 120 dB 5)
operational range of frequencies from few Hz to
about 100 kHz 6) capability of point-source
identification and tracking 7) modularity. In
order to test and operate SUD the INFN-LNS offer
a unique underwater facility worldwide two
scientific infrastructures equipped with shore
laboratories and underwater electro-optical
cables connecting shore with deep-sea. One is
located 25 km SE of the port of Catania (Sicily),
already used for ONDE the other one is located
at 3500 m depth 90 km South East of Capo Passero
(Siracusa, Sicily), and will be soon operative.
The expected sensitivity of the SUD antenna,
better than the one achieved for ONDE, will offer
the unique opportunity of long-term on-line
monitoring of sounds in a range of 100 km,
depending on source frequency and amplitude,
allowing a wide range of interdisciplinary
studies. Sperm-whale clicks could be identified
at a distance several tens of km. SUD will also
allow reconstruction of source position and
movements and, at the same time, pulse shape
study of acoustic signals. These tasks will be
fundamental in order to perform studies on sound
sources in different research fields geophysics,
acoustical oceanography, bioacoustics,
astro-particle physics et cetera.
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SUD (Sound underwater Detector) for Ideas FP7
INFN LNS (Main Infrastructure) Integration,
Installation, data Acquisition Mechanics, Power
electronics DAQ electonics, DAQ and analysis
software Roma DAQ Electronics, DAQ and
analysis software Napoli DAQ Electronics, DAQ
and analysis software Pisa RD Optical Fiber
Hydros and analysis software Uni-CT RD
Semiconductor Hydrophones Valencia Calibration,
DAQ software Sheffield DAQ Electonics, DAQ and
analysis Software Deep sea calibration
(calibrator) CIBRA DAQ software Bioacoustic
analysis Software
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ONDE Phase 2 On the Alcatel frame
192 kHz 24 bit 4CH
ADC
preamp
AES protocol
AES
DAQ on shore
E/O Modem transmitter
100 km optical fibre
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Modem Transmitters
The iConverter T3/E3 manageable media converter
is a member of the modular iConverter product
family. It provides standard T3 (44.736Mbps) or
E3 (34.368Mbps) coax to fiber conversion and can
be used by telco service providers and enterprise
users to connect to devices such as PBXs,
multiplexers, routers and video servers via
fiber. The T3/E3 operates in pairs extending
distances over fiber, improving noise-immunity
and quality of service while improving intrusion
protection and network security. Being framing
independent, the T3/E3 operates with framed or
unframed data. It also operates with channelized
or fractional unchannelized data streams. It
supports B3ZS line coding for T3 (DS3) and HDB3
for E3.
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Bioacoustics in SUD
Position tracking Pulse shape recognition Animal
identification Study of cetaceans
routes Control tower for cetaceans ?
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LIDO (LIsten to Deep Ocean) FP7
Univ. Of Catalunya INGV INFN ...
Recover SN1, Recover OnDE ? make a unique
station pilot experiment for all Esonet
Nodes
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Acoustics Developments for phase 2 and beyond

• Proposal for hydrophone displacement
• 2 hydrophones per floor on normal floors (14
  x2)
• 4 hydrophones per floor on new floors (2 x 4)
• 4 hydrophones at the tower base
• 4 hydrophones on the Alcatel DC/DC frame ?

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Acoustics NEMO Phase 2
NEMO Phase 2 Integrate acoustic positioning
system and acoustic physics How Use
hydrophones sensible in the range (30 Hz-70 kHz)
and suitable for 3500 m depth Sample signals
underwater (24 bit, 192 kHz) Use the FCMb as
data carrier (optical link) Perform data
analysis (physics and a.p.) on shore
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Acoustics Floor lay-out
192 kHz, 24 bit, 2CH
ADC
preamp
Hydrophones
AES3 protocol
DAQ on shore
FCMB
FMCI
AES protocol
Data
Experiment Clock
100 km optical fibre
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FMCb Modifications
Included in FCMb (2.1) production (see M. Bonori)
Off shore modifications Hardware generate a
24.576 MHz for the A/D receive 1 (2) AES3
stereo streams on dedicated line(s) Firmware h
ydrophone data transmission in the optical
stream On shore modifications Hardware generat
e a 24.576 MHz for the A/D transmit 1 (2) AES3
stereo streams dedicated line(s) Firmware insert
experiment (GPS) time stamp in the AES frame
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The Reson Hydrophone TC 4042-C
Special production for NEMO Test _at_ 350
bar calibration _at_ f gt2 kHz Piston test _at_ 250 Hz
1 Hz - 80 kHz 1 Hz to 50 kHz 194dB 3 re 1V/uPa
Omnidirectional 2dB at 40 kHz 270 3 dB at 40
kHz 1500 m 2000 m Aluminum (Seabronze for NEMO)
Usable Frequency range Linear Frequency range
Receiving sensitivity nominal Horizontal
Directivity Pattern Vertical Directivity
Pattern Operating depth Survival depth Metal
body
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The Reson Hydrophone TC 4042-C
To obtain V / sqrt(Hz) add -177 dB
Expected signals (10 Hz-100 kHz) sea ?
27 mPa ? 40 uV hydro pre ? 14 mPa ? 20 uV
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The Reson Preamp
Change the Aluminum vessel with a (plastic ?) oil
filled one or a moulding 1) lighter, easier to
build, cheaper, better corrosion resistance 2)
safer for acoustic coupling
Hydrophone housing
RESON Hydrophone 4042-C
RESON preamp board
Preamp Board test at 350 bar (report
available) OK ! And also Preamp
Characterization Jensen Transformer test at 350
bar OK !
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A/D Board (4 Channels)
PCM4204EVM evaluation board for PCM4204
Four High-Performance Delta-Sigma Analog-to-Digita
l Converters 24-Bit Linear PCM or 1-Bit Direct
Stream Digital (DSD) Output Data Supports PCM
Output Sampling Rates up to 216kHz Dynamic
Performance PCM Output Dynamic Range 118dB
THDN -105dB
Bad performances at 192 kHz
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Work in progress study of the evaluation board
4 channel ADC RME ? read with WaveIn (W) and
Mixcraft (M)software
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A/D Board (2 Channels)
PCM4222EVM evaluation board for PCM4222 CDB5381
evaluation board for CS5381 Better and smaller
(to fit the FCM mechanics)
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Data acquisition on shore
PCI Busmaster Digital I/O Card 32 Channels
AES/EBU Interface 24 Bit / 192 kHz Digital
Audio 32 x 16 Matrix Router 2 x MIDI I/O Quick
Boot
(digital AES stereo inputs ? 16 Channels in 1
board ????? )
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Acoustic positioning in Phase 1
Acoustic Positioning
RS232
SCI
Optical Link
DSP
FCMb
FCMI
Clock
Ethernet
Data Manager
Clock
Chronos
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Acoustic data in Phase 2
On - shore
Acoustic Positioning
preamp
Optical Link
AES3
AES3 GPS time
ADC
FCMb
FCMI
?
Ethernet
RME
preamp
Optical Link
AES3
ADC
FCMb
FCMI
AES3 GPS time
Off - shore
Clock
Chronos
Acoustic Physics
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Acoustic Positioning with our hydrophones

• We just become carrier of the acoustic
  information
• Beacon signal ? acquired at 192 kHz, 24 bits
  (AES3) ? transported on shore as it is
• FCMI adds absolute time info (in the AES3 stream)
  ? ethernet (1... 16 ... 32 channels)
• ACSA

NEMO
Acoustic Positionig
AES3 time
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Acoustic Positioning with our hydrophones
Requirements 1 us time syncro ( feasible,
work in progress) Hydro monitor at the tower
base ( requires another FCM ! see A.
DAmico )
Requirements can be satisfied
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Acoustic Positioning with our hydrophones
Costs (lt)4000 per floor 2 Hydro 2 pre
4 Transformers 1 Board
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Acoustic Physics with our hydrophones
Ocean Noise (and neutrinos) Sensitivity ?
Electrical noise (DC/DC converters) Acousti
c noise (Beacons, DC/DC) Biology Sensitivity
OK source tracking Geophysics Response to
low frequencies (Hydro ok, electronics?)
Technological added value (for the km3 ?)
Transmission, acquisition and analysis of huge
amounts of data Implementation of tracking and
bkg reduction algorithms Phase2 the first
experiment capable to acquire optics acoustics
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Perspectives
Acoustic events (only muon neutrinos, WB flux)
recorded with a 1 km3 acoustic detector in 1 year.
Event generation volume can 3 km radius x 3 km
height)
Very Preliminary
Hydrophone threshold 5 mPa
S. Saccone, Laurea thesis
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Perspectives ? Science-fiction ?
Optical acoustics ????? optical muon
direction ?E acoustic muon range (using
direction info for bkg rejection)
Muon calorimetry ???