METHOD MEASURING DISTANCE TO CONTROLLED OBJECT ( ITS VERSIONS ) Russian patent published in 1999 - IPC

FIELD: underwater acoustics, design of underwater range finding systems. SUBSTANCE: in accordance with method pulse acoustic signal is emitted from controlled object in step with start of time reading in reception points on controlled objected separated by distance 1 that is less than length of wave of acoustic signal. Phase and group times of delay are determined on basis of measurement of parameters of received signals, then desired range is computed. In this case acoustic signal is emitted at angle of side slip depending on density of water and soil and average velocities of propagation of sound in layer of water close to bottom and of . longitudinal waves in layer of soil close to bottom. Signal is received according to versions by hydrophones put into or placed on soil. Value of range is found in both versions by invariant velocity. EFFECT: increased range and decrease error while measuring ranges in basins of limited dimensions under conditions of presence of reflected signals and heavy dispersive distortions. 2 cl, 1 dwg