Broadband Measurements of Underwater Acoustic Target Strengths of Panels of Tuna Nets.
Abstract
Sample panels of tuna nets of three different mesh sizes (1-1/4,2 and 4-1/2 inches) and two twine types (twisted and braided) were placed in a nearly anechoic chamber, insonified with a broadband sound source, and the returns recorded and analyzed to determine target strength. Measurements were made with panels perpendicular to the source and with a 35-degree bend at the midline. Target strengths ranged from -21 dB to -4 dB for the perpendicular panels and from -23 dB to -16 dB for the bent panels. Two-inch braided net was the most reflective, though all panels produced sufficiently strong returns to allow porpoises to detect them acoustically. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 1977
- Accession Number
- ADA042311
Entities
People
- D. K. Lungblad
- J. S. Leatherwood
- R. A. Johnson
- W. E. Evans