Results of the test of power parametric array at the marine range of the Hydrophysical research institute in Sukhum (Abkhazia) are presented in the paper. Methods of nonlinear acoustics are discussed for hydrographical research, which appeared when sharp directed wide frequency band acoustical signal from parametric array will be fitted to frequency pattern of the marine waveguide. Results of the research show the single mode marine waveguide excitation by parametric array in the wide frequency band are obtained. The ability to compress the wide frequency band acoustical signal under it propagation due to waveguide dispersion is shown. This compression leads to increase the signal-to-noise ratio. Some aspects of sharp directed parametric array application for hydrographical research at the Black sea and in Arctic are considered as well.
43.30.Bp Normal mode propagation of sound in water
$^1$Russian state university of oil and gas by I.M. Gubkin, Physics chair, Leninsky prosp. 65, Moscow, 119991, Russia
$^2$Acoustics institute, Shvernik str. 4 , Moscow, 117036, Russia
$^3$Hydrophysical institute, Sukhum, Abkhazia