METHOD OF DETECTION OF OBJECTS LYING IN THICKNESS OF BOTTOM GROUND Russian patent published in 2006 - IPC G01S15/04 

FIELD: hydroacoustics and ocean engineering; search of objects lying under ground and invisible for side-looking sonar.

SUBSTANCE: proposed method consists in radiating signal from carrier of sonar equipment provided with transceiving array of side-looking sonar, radiating and receiving arrays and receiving reflected signal from object by means of the same array, measuring time "t" of signal propagation and calculating distance "r" to object; then sonar equipment array is moved above bottom relative to expected position of object and display spatial and time position of object; in synchronism with radiation of said side-looking sonar array, pulse acoustic signal is radiated by additional radiating acoustic array directed in vertical plane at incidence angle of θ_rad=arcsin[(1-ρ² ₁₂)^1/2.(1-ρ² ₁₂.C² ₁₂)^-1/2], where ρ₁₂=ρ₁/ρ₂, C₁₂= C₁/C₂, ρ₁, C₁, ρ₂, C₂ is density and velocity of sound in water and in ground respectively; acoustic signal reflected from object and re-radiated into water medium is received and additional radiating array which is directed in vertical plane is moved to height Z₁ above bottom connected with depth Z₂ of expected position of object in thickness of bottom ground by relationship Z₁=Z₂/ρ₁₂, distance "r" to object is calculated by the following formula: .

EFFECT: enhanced efficiency of search and detection.

1 dwg