Mk.VIII
2.85
www.itp101.com
NPL Transducer Polar Plot
(National Physical Laboratory)
Acoustic Systems Trainer – SONAR
R&D Platform
Main Menu
SONAR Signal Analyser(SSA)
Doppler
SSA Demo…..then click
Scattering
CW Oscillator
CTFM SONAR
Passive SONAR
Formulae
Active SONAR
Dev & Underwater Sounds
Range Resolution
Acoustic Spectrum
Transducer BeamWidth
AST Console
Transducer Beam Plot
Installations
Acoustic Systems Trainer – SONAR
Britannia Royal Naval College
: US Naval Academy – Weapons Engineering
: Royal Norwegian Navy-SONAR Engineering
: Royal Saudi Naval Force – Saudi Arabia
: King Fahd Naval Academy – Saudi Arabia
: Alenia Marconi Systems – Dundridge College
: HMS Daedalus – RN Fleet Air Arm
: HMS Collingwood – RN Maritime Warfare School
: Britannia Royal Naval College – Dartmouth
: University of Plymouth – Underwater Research
: Texas A&M University – Marine Engineering
: PLPE Kuala Lumpur - Malaysia
: Singapore Navy – ASW School
Acoustic Systems Trainer – SONAR
R&D Platform
Royal Navy – Maritime Warfare School – HMS Collingwood
Acoustic Systems Trainer – SONAR
R&D Platform
Alenia Marconi Systems – Dundridge College
Acoustic Systems Trainer – SONAR
R&D Platform
Royal Saudi Navy
T.I.N.S
Royal Saudi Navy – Technical Institute Naval Studies
Acoustic Systems Trainer
King Fahd Naval Academy
Acoustic Systems Trainer – SONAR
R&D Platform
TAMUG – Texas A&M University Galveston
Main Menu
SONAR Signal Analyzer (SSA)
SSA Menu
Instrument Task Bar
Oscilloscope
SETUP
Spectrum Analyzer
Default Text
Multi Meters
AWG with Burst
Transient Recorder
Main Menu
Acoustic Spectrum
Sonic Regions
Infra-Sonic
Sonic (Audio)
30Hz
18kHz
2kHz
Passive Sonar
Towed Arrays
Long Range
Sonar
Ultra-Sonic
9kHz
12kHz
Active
Dipping
Search
Sonar
Sonar
50kHz
200kHz
Torpedoes(Attack)
AST
Minehunting
High Definition
Oceanographic
Sonar
A.U.D.I – Acoustic Underwater Development Instrument
Main Menu
SSA
Instrument Task Bar
Dual Channel
One Shot
Memos
Cursors
Ref Channels
Multi Trigger
Maths
Auto Set-up
Configurable
Peak-Peak
RMS
Mean
Crest
Frequency
Maths
Auto Freq..
Over 190 days
Ref Channels
Cursors
Scroll
Scan
Memos
Zoom
Var Axis
Dual Ch.
Log Scale
Averaging
Cursors
Windows
Memos
Harmonic
Analyzer
Sine
Triangle
Square
DC
White Noise
Sweep
Symmetry
Attenuation
Instrument
Configuration
Text
Colours
Start-up
CAL files
Duty Cycle
Directories
Exit
Main Menu SSA Menu
Oscilloscope
Main Menu SSA Menu
Multi Meters
Main Menu SSA Menu
Transient Recorder
Main Menu SSA Menu
Spectrum Analyzer
Main Menu SSA Menu
Function Generator
AWG + Burst
Main Menu SSA Menu
SETUP
Duty Cycle
Colors
Active Instruments
Default Text
Main Menu SSA Menu
Doppler
The Doppler effect is the frequency shift which occurs when a signal is transmitted
from a moving platform towards a receiver, conversely, the transmitter could be
stationary and the receiver could be in motion.
In the most complex case, both transmitter and receiver could be moving with respect
to each other.
Whatever the case, there is a resultant change in frequency which can be detected and
used to determine the speed and direction of motion.
The following set-up is one method to enable the Doppler component to be extracted
from a moving target echo.
Use the Transient Recorder with the output from the Detector to record the Doppler
shift.
Main Menu
Doppler
Movie
Observe the Phase change of the Doppler signal when
the target changes direction, and the change in Signal
Level as the target opens and closes
Doppler
Notes
AUX O/P GAIN <50%
TX2 O/P GAIN <50%
Detector IN/OUT ?
Align Receiver
Vary Speed/Direction
DC Coupling
.04 Secs
1,000 Samples
20V Sensitivity.
OUT
IN
Detector
CW Transmitter
Receiver
Main Menu
Range Resolution
Movie
Observe how both targets are resolved with
optimum Pulse Width, and poor target
discrimination with increasing PW.
Range Resolution
Notes
Align ‘Grill’ Target
Observe Two Echoes
Vary PRF/PW
SCOPE
Reversible TX/RX
Grill Target
Main Menu
Active SONAR
Movie
Observe the Transducer Ringdown, and the
smaller amplitude echoes which appear to
‘follow’ the large target echo.
Active SONAR
Movie
Observe how Pulse Width + Ringdown Time determines
the Minimum Range, and the Pulse Repetition Frequency
or PRF, sets Maximum Range of the SONAR.
Active SONAR
Notes
Align Small Target
Vary Speed/Direction
Identify Echoes
Vary PRF/PW/TX FREQ
SCOPE
Reversible TX/RX
Target
Main Menu
Passive SONAR (Pulse)
Movie
Observe how the Active SONAR transmission, and
the Target Echo are detected by the Passive SONAR
Hydrophone.
Passive SONAR (Pulse)
Notes
Align TX and Hydrophone
Vary TX FREQ
See Spectrum Analyzer
SCOPE
Projector TX
Hydrophone RX
Main Menu
Volume Scattering
Notes
Align Target
Vary Speed/Direction
Scatter Salt
SCOPE
Reversible Tx/Rx
Target
Main Menu
Beam Plot
Movie
Observe the smaller Sidelobes either side of the Mainlobes.
These manual plots are only intended to give an approximation
of the transducer’s Beam Pattern.
See the NPL Plot on the next screen which was recorded in a
very large, acoustically damped tank under ideal conditions.
Side Lobes
BW = 8º at-3dB
Main Lobe
National Physical Laboratory
Transducer Polar Plot – 192kHz
Beam Plot
Notes
Acoustic Damping
AUX O/P GAIN <50%
Detector IN/OUT ?
Rotate Test Transducer…
CW…then CCW
DC Coupling
.04 Secs
1,000 Samples
20V Sensitivity.
OUT
IN
Detector
Rotate Handle
Projector
Acoustic Damping
Test Transducer
Main Menu
Beam Width
Notes
Acoustic Damping
Observe Spectrum Analyzer
Slide Test Transducer…
Set 0dB
Slide to first –3dB point…
Back to 0dB…
Slide to second –3dB point
Calculate BW
SPECTRUM
CW Signal Source
Acoustic Damping
Test Transducer
Main Menu
Passive SONAR (CW)
Notes
Observe SCOPE…
Slide Hydrophone…
Vary TX FREQ
Observe SPECTRUM
Resonant Frequency?
SCOPE
Projector TX
Hydrophone RX
Main Menu
Continuous Wave (CW) Oscillator
Movie
Observe the change in Frequency displayed
in the Time Domain on the Oscilloscope.
Continuous Wave (CW) Oscillator
Movie
Observe the change in Fundamental Frequency displayed
in the Frequency Domain on the Spectrum Analyzer.
Continuous Wave (CW) Oscillator
Movie
Observe the Fundamental (1st harmonic) and
related Harmonics in the Frequency Domain.
Continuous Wave (CW) Oscillator
Notes
Observe SCOPE…
Slide Hydrophone…
Vary TX FREQ
Observe SPECTRUM
Resonant Frequency?
SCOPE
Projector TX
Hydrophone RX
Main Menu
CTFM SONAR
Notes
•AUX O/P GAIN <50%
•TX2 O/P GAIN <20%
•Detector IN/OUT ?
•Align Target
•Vary Range of Target
•Select- Preset 1
OUT
IN
Detector
CTFM Tx and Rx
Acoustic Damping
Main Menu
Development
Suggested development projects*Underwater communications.
Depth finder.
Air curtains.
Cavitation investigation.
Vortex activity.
Bottom profiling.
CTFM SONAR.
Refraction.
Signature analysis.
Parametric SONAR.
Target bearing detection.
Tracking
MAD – Magnetic Anomaly Detector
Shallow Water Back Scattering
*Some projects have already been completed.
Underwater Sound Analysis
Acoustic Systems Trainer-Sonar Add-on
Underwater Sound Analysis
Features-
Sound Library-
Low Frequency Hydrophone
Torpedo Strike
Dolphins
Whales
Snapping Shrimp
Cracking Ice
Diesel Engine
Cavitation
Warship
Tug
Pump
Explosion
Sonarbuoy
US Navy LFAS
Earthquake
Sound Card compatible
Headphones
Roaming Passive Target
Spectrogram Software
Selectable FFT Points
Scroll Plot
Spectrum Analyzer
Scope Display
Underwater Sound Analysis
Spectrogram
Movie
Dolphins
Main Menu
Formulae
Power Gain = 10 log10 Pout decibels
Pin
Passive SONAR equation
SE = (SL-PL) – N - DT
Active SONAR equation
SE = (SL+TS-2PL) – N - DT
Speed of Sound in Sea Water (Wilson)
C = 1449+4.6T-0.055T2+0.0003T3+(1.39-0.012T)(S-25)+0.017D
Doppler Shift
f = + 0.69Hz per knot per kHz
f = + 1.33Hz per metre per second per kHz
See reference text ‘SONAR FOR PRACTISING ENGINEERS’
Main Menu
AST Mk VIII Console
SONAR
Signal
Analyzer
PRF
TX Frequency
Pulse Width
Controls
Echo Threshold
Target Speed
Controls
General
Purpose
&
AUX Amps
Array
Beam
Steering
Power
Supply
Outputs
Main Menu