Upload
kedma
View
39
Download
0
Tags:
Embed Size (px)
DESCRIPTION
Measuring Angular Variation of Target Strength for Simple Geometric Objects. CDR Ed Tucholski US Naval Academy Annapolis, MD. Reflected Wave. Object. Transmitter/ Receiver. Original Wave. Distance r. Drawing Source: Wikipedia. Active Sonar Equations. - PowerPoint PPT Presentation
Citation preview
Measuring Angular Variation of Target Strength for Simple Geometric ObjectsCDR Ed TucholskiUS Naval AcademyAnnapolis, MD
Active Sonar EquationsNoise Limited CaseReverberation Limited CaseFunction of geometry and scattering direction
Target StrengthThe reflected intensity (pressure) is dependent on the reflection, diffraction, and interference of sound scattered off the object. Target Strength is highly dependent on the scattering angle.The teaching point of this demonstration is to show the angular dependence. For simplicity, we will measure
ApparatusData AcquisitionSerial to USBTekVisaExcelTransducers
Envelope Detector
Square Plate
Circular Plate
CylinderL
Cylinder 360o Target Strength
Target Strength is a Decibel
Demonstration
SettingsWavetek Model 29Sine 40.04 kHz18.1 V p-pSR560Source A, AC Coupled6 dB/oct band pass, 10k-100k HZLow NoiseGain = 20
Scope 1Ch 1 10 V/divCh 2 50 mV/divt = 10.0 msScope 2Ch 2 100 mV/divt = 4.00 sVXM-1 72 s/rev