Models of Propagation of Acoustic Signals and Noise in Oceanic Waveguides with Wavy Surface and the Effectiveness of Spatial Signal Processing

We study the effectiveness of spatial signal processing at the apertures of the vertical and horizontal antenna arrays for acoustic waveguides with irregular free boundaries. The main attention is paid to a joint use of statistical models of signal and noise, which is generated near the waveguide boundary by dipole sources, and optimal algorithms for processing of partially coherent signals. The proposed signal and noise models allow for the effects of multiple scattering of acoustic modes. On the basis of the obtained theoretical results, we perform computations of the gain of the antenna arrays of various orientations for an oceanic waveguide with a wavy surface and regular parameters, which are typical of shallow sea. The dependences of the antenna-array gain on the distance and wind velocity are analyzed for various spatial-processing algorithms. The influence of the intermode signal correlations and the statistical model of noise on these results is discussed.