Utilizing an Extended Target for High Frequency Multi-beam Sonar Intensity Calibration
An interest in expediting intensity calibration procedures for Multi-Beam Echo-Sounders (MBES) to be used for acoustic backscatter measurements exists. Current calibration methods are time-consuming and complicated, utilizing a target that is quite different from the seafloor. A target was constructed of irregularly oriented chain links arranged in a 'curtain' simulating an extended scattering surface, such as the seafloor. Tests with a 200-kHz SIMRAD EK60 Split-Beam Echo-Sounder (SBES) were performed to investigate the targets angular- and range-dependent scattering strength. These tests suggest that the backscatter 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. This calibration test was performed with the target at normal incidence, and the final output is a beam-dependent calibration coefficient determined from the sonar equation.
John completed his BSME with Acoustics Concentration from the University of Hartford in May of 2012, and started his work at CCOM shortly after in June. John's research areas include Underwater Acoustics and various echo sounding techniques.