Investigation of the sound field structure in the ocean with a deep-water reception

The results of studying the angular and energy structures of a sound field at great depths (880 and 1100 m) with the emission of pseudonoise signals (a frequency range of 1–4 kHz) in the upper layers of the ocean below the velocline (at a depth of 200 m) are presented. The results refer to two ocean regions characterized by the presence of a single-axis deep-water sound channel. The sound field structure at great depths is compared with that recorded at the source depth. The experimental data for the first two convergence zones are compared with the calculations by the ray method. A conclusion is made that, on the whole, the basic regularities of the field structure at great depths are adequately described by the ray theory. However, the spatial positions of the convergence zones observed in the experiment differ from those predicted by the ray calculations. Moreover, a closer examination of the field characteristics shows that the parameters of the angular and energy structures noticeably deviate from the calculated values.