ATI's Fundamentals of Sonar Transducer Design course

This three-day course is designed for sonar system design engineers, managers, and system engineers who wish to enhance their understanding of sonar transducer design and how the sonar transducer fits into and dictates the greater sonar system design. Topics will be illustrated by worked numerical examples.

What You Will Learn:

• Basic acoustic parameters that affect transducer designs including:
  • Aperture design
  • Radiation impedance
  • Beam patterns and directivity
• Fundamentals of acoustic wave transmission in solids including the basics of piezoelectricity
• Basic modeling concepts for transducer design
• Transducer performance parameters that affect radiated power, frequency of operation, and bandwidth
• Sonar projector design parameters
• Sonar hydrophone design parameters

From this course you will obtain the knowledge and ability to perform basic sonar transducer systems engineering calculations, identify tradeoffs, interact meaningfully with colleagues, evaluate systems, understand current literature, and how transducer design fits into greater sonar system design.

Course Outline:

1. Overview Review of how transducer and performance fits into overall sonar system design.
2. Waves in Fluid Media. To understand basic transducer design principals, the student needs to given a background on how the transducer creates sound energy and how this energy propagates in fluid media. This section reviews the basics of sound propagation in fluid media and includes a review of the following topics:
   1. Plane Waves
   2. Radiation from Spheres
   3. Linear Apertures Beam Patterns
   4. Planar Apertures Beam Patterns
   5. Directivity and Directivity Index
   6. Scattering and Diffraction
   7. Radiation Impedance
   8. Transmission Phenomena
   9. Absorption and Attenuation of Sound
3. Equivalent Circuits: Transducers are generally modeled as equivalent electrical circuits. A basic understanding of this approach will enable the student to understand the relationship between transducer parameters and performance and conduct basic analysis of transducer designs. This section will build on the following topics:
   1. Mechanical Equivalent Circuits
   2. Acoustical Equivalent Circuits
   3. Combining Mechanical and Acoustical Equivalent Circuits
4. Waves in Solid Media: A transducer is constructed of solid structural elements. As such, the student needs to be provided with a background in how sound waves propagate through solid media. This section builds on the previous section and develops equivalent circuit models for various transducer elements. Piezoelectricity is introduced in this section. This section reviews the following topics:
   1. Waves in Homogeneous, Elastic Solid Media
   2. Piezoelectricity
   3. The electro-mechanical coupling coefficient
   4. Waves in Piezoelectric, Elastic Solid Media
5. Sonar Projectors: This section combines the concepts of the previous sections and developes the basic concepts of sonar projector design. Basic concepts for modeling and analyzing sonar projector performance will be presented. Examples of sonar projectors will be presented and will include spherical projectors, cylindrical projectors, half wave-length projectors, tonpilz projectors, and flexural projectors. Limitation on performance of sonar projectors will be discussed.
6. Sonar Hydrophones: In this section, the basic concepts of sonar hydrophone design will be reviewed. This section will include the analysis of hydrophone noise and extraneous circuit noise that may interfere with hydrophone performance. Topics include:
   1. Elements of Sonar Hydrophone Design
   2. Analysis of Noise in Hydrophone and Preamplifier Systems
   3. Specific Application in Sonar Hydronpone Design
      1. Hydrostatic hydrophones
      2. Spherical hydrophones
      3. Cylindrical hydrophones
      4. The affect of a fill fluid on hydrophone performance