Analysis of sonar navigation systems in coastal zone

Acoustic field research in the shallow sea is actually a complex experimental and mathematic challenge. To solve the matter of general problematic obstacle faces overcoming of non-homogeneity in boundary conditions. The boundary between marine water and air could be presented as being mild acoustically, but the frontier between sea water and bottom looks like an impedance one. The paper presents the designed method that is based on application of some mathematic patterns of “directed” Green's functions. The “directed” Green's function coincides with Green's function of free space in the specified interval. This article offers a designed algorithm of field calculation in the marine wedge confined by air and rocky bottom. The achieved digital results are compared and verified against the earlier investigated homogeneous boundary conditions. Root-mean-square error in computation under the classic standard results comparison and estimated by the proposed method of “directed” Green's functions doesn't exceed 0,05. The calculation time of one variant by the average power computer equals about 1 minute. The conducted marine tests and trials in the sea nature displayed reasonable coincidence with theoretical computation — an error doesn't exceed 40%.