Utilizing an Extended Target for High Frequency Multi-beam Sonar Intensity Calibration
Title | Utilizing an Extended Target for High Frequency Multi-beam Sonar Intensity Calibration |
Publication Type | Thesis |
Year | 2014 |
Authors | Heaton, JL |
Degree and Program | Master of Science in Mechanical Engineering |
Number of Pages | 75 |
Date Published | 09/2014 |
University | University of New Hampshire |
Location | Durham, NH |
Keywords | acoustics, calibration |
There exists an interest in expediting intensity calibration procedures for Multi-Beam Echo-Sounders (MBES) to be used for acoustic backscatter measurements. Current calibration methods are time-consuming and complicated, utilizing a target that is different from the seafloor. A target of irregularly oriented chain links arranged in a 'curtain' was constructed to simulate an extended surface, like the seafloor. Tests with a 200-kHz SIMRAD EK60 Split-Beam Echo-Sounder (SBES) to investigate the targets scattering strength were performed. These tests suggest that the scattering strength depends on the number of scattering elements. A 200 kHz Reson SeaBat T20-P MBES was calibrated with the same target. This MBES was rotated so that all beams were incident on the target. The final output is a beam-dependent calibration coefficient determined from the sonar equation. The T20-P was then used to collect backscatter in the field along a local survey line, where data were compared to the EK60. |