Modeling and Measuring Fish Backscatter at Multiple Frequencies
Abstract
The long-term goals of the Principal Investigators are to quantify, understand and predict acoustic backscatter of fish. Objectives of this project are to: quantify the sensitivity of theoretical backscatter models to the resolution of fish body and swimbladder digitized data; compare empirical measures of resonance backscatter to predicted amplitudes from theoretical backscatter models; examine and compare efficacy of multi-frequency and broadband sonars to discriminate targets; and to acoustically quantify size distributions, abundances, and behavior of fish. Acoustic backscatter models are based on digitized x-ray images of fish body and swimbladder morphology. Back-scatter amplitude as a function of acoustic wavelength, fish length, and fish aspect is estimated using Kirchhoff ray-mode scatter models 1,2. Model predictions are used in computer simulations to estimate population abundances, and compared to empirical backscatter measurements from laboratory and in situ field measurements during mobile surveys.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 30, 1998
- Accession Number
- ADA544783
Entities
People
- J. Michael Jech
- John K. Horne
Organizations
- National Oceanic and Atmospheric Administration