Mk.VIII 2.85

NPL Transducer Polar Plot (National Physical Laboratory)

SONAR Signal Analyser(SSA) Passive SONAR Active SONAR Range Resolution Transducer BeamWidth Transducer Beam Plot Scattering CW Oscillator CTFM SONAR Doppler Formulae Dev & Underwater Sounds SSA Demo…..then click AST Console Main Menu Acoustic Systems Trainer – SONAR R&D Platform Installations Acoustic Spectrum

Acoustic Systems Trainer – SONAR : 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 Britannia Royal Naval College

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 – Technical Institute Naval Studies Royal Saudi Navy T.I.N.S

Acoustic Systems Trainer King Fahd Naval Academy

Acoustic Systems Trainer – SONAR R&D Platform TAMUG – Texas A&M University Galveston Main Menu

AWG with Burst Oscilloscope Spectrum Analyzer Instrument Task Bar SETUP Default Text Multi Meters Transient Recorder Main Menu SSAMenu SSA Menu SONAR Signal Analyzer (SSA)

Acoustic Spectrum Infra-SonicSonicUltra-Sonic (Audio) 30Hz18kHz 2kHz9kHz12kHz50kHz200kHz Passive Sonar Towed Arrays Long Range Sonar Active Search Sonar Dipping Sonar Torpedoes(Attack) AST Minehunting High Definition Oceanographic Sonar Sonic Regions Main Menu A.U.D.I – Acoustic Underwater Development Instrument

 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  Exit  Sine  Triangle  Square  DC  White Noise  Sweep  Symmetry  Attenuation  Instrument Configuration  Text  Colours  Start-up  CAL files  Duty Cycle  Directories SSA MenuMain Menu SSA Instrument Task Bar

Main Menu Oscilloscope SSA Menu

Main Menu Multi Meters SSA Menu

Main Menu Transient Recorder SSA Menu

Main Menu Spectrum Analyzer SSA Menu

Main Menu Function Generator AWG + Burst SSA Menu

SETUP Colors Duty Cycle Default Text Active Instruments Main MenuSSA Menu

Main 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.

Movie Doppler 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  DC Coupling .04 Secs  1,000 Samples  20V Sensitivity. Notes  AUX O/P GAIN <50%  TX2 O/P GAIN <50%  Detector IN/OUT ?  Align Receiver  Vary Speed/Direction OUTIN CW TransmitterReceiver Detector 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 Reversible TX/RXGrill Target  SCOPE 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 Reversible TX/RXTarget  SCOPE Main Menu

Passive SONAR (Pulse) Movie Observe how the Active SONAR transmission, and the Target Echo are detected by the Passive SONAR Hydrophone.

Projector TXHydrophone RX Passive SONAR (Pulse) Notes  Align TX and Hydrophone  Vary TX FREQ  See Spectrum Analyzer  SCOPE Main Menu

Volume Scattering Notes  Align Target  Vary Speed/Direction  Scatter Salt Reversible Tx/RxTarget  SCOPE

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.

National Physical Laboratory Transducer Polar Plot – 192kHz BW = 8º at-3dB Main Lobe Side Lobes

Beam Plot  DC Coupling .04 Secs  1,000 Samples  20V Sensitivity. Notes  Acoustic Damping  AUX O/P GAIN <50%  Detector IN/OUT ?  Rotate Test Transducer…  CW…then CCW OUTIN Detector ProjectorTest Transducer Rotate Handle Acoustic Damping 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 CW Signal SourceTest Transducer Acoustic Damping  SPECTRUM

Main Menu Passive SONAR (CW) Notes  Observe SCOPE…  Slide Hydrophone…  Vary TX FREQ  Observe SPECTRUM  Resonant Frequency? Projector TX Hydrophone RX  SCOPE

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 (1 st harmonic) and related Harmonics in the Frequency Domain.

Continuous Wave (CW) Oscillator Notes  Observe SCOPE…  Slide Hydrophone…  Vary TX FREQ  Observe SPECTRUM  Resonant Frequency? Projector TX Hydrophone RX  SCOPE Main Menu

Notes AUX O/P GAIN <50% TX2 O/P GAIN <20% Detector IN/OUT ? Align Target Vary Range of Target CTFM Tx and Rx Acoustic Damping Main Menu CTFM SONAR OUT IN Detector Select- Preset 1

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-  Low Frequency Hydrophone  Sound Card compatible  Headphones  Roaming Passive Target  Spectrogram Software  Selectable FFT Points  Scroll Plot  Spectrum Analyzer  Scope Display Sound Library-  Torpedo Strike  Dolphins  Whales  Snapping Shrimp  Cracking Ice  Diesel Engine  Cavitation  Warship  Tug  Pump  Explosion  Sonarbuoy  US Navy LFAS  Earthquake

Spectrogram Underwater Sound Analysis Main Menu Dolphins Movie

Main Menu Formulae Power Gain = 10 log 10 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 = T-0.055T T 3 +( T)(S-25)+0.017D Doppler Shift  f = Hz per knot per kHz  f = Hz per metre per second per kHz See reference text ‘SONAR FOR PRACTISING ENGINEERS’

General Purpose & AUX Amps Array Beam Steering Power Supply Outputs AST Mk VIII Console S ONAR S ignal A nalyzer PRF TX Frequency Pulse Width Controls Echo Threshold Target Speed Controls Main Menu