Reference for citation: Vagin A. V., Vorotyntseva A. S. Fresnel zones formation in acoustic sounding of bottom soil. Journal of Instrument Engineering. 2025. Vol. 68, N 10. P. 876–885 (in Russian). DOI: 10.17586/0021-3454-2025-68-10-876-885.

Abstract. Acoustic profiling of bottom soil is an alternative way of exploring the World Ocean. When an acoustic wave hits the surface, reflection, absorption, and scattering processes occur. If the thickness of the layers is much less than the acoustic wavelength, then the reflection can be represented as radiation from a secondary source of acoustic waves in the opposite direction. The size of the secondary source is determined by the irradiation area, which consists of certain zones called Fresnel zones. The physical foundations of the formation of Fresnel zones in bottom soil sounding for normal and inclined wave incidence are considered. Expressions for calculating Fresnel zones are presented.

Keywords: acoustic profiler, bottom soil, reflection, Fresnel zone

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