METHOD FOR DETECTING UNDERWATER OBJECTS (OPTIONS) AND DEVICE FOR ITS IMPLEMENTATION Russian patent published in 2018 - IPC G01S15/00 

FIELD: hydraulic engineering.

SUBSTANCE: invention relates to the field of hydroacoustics and can be used in sonar detection devices for underwater objects intended for use in areas with a high level of reverberation interference in the conditions of shallow water, complex bottom relief and water surface disturbance. Technical result is achieved by creating a method for detecting underwater objects, which consists in that the underwater controllable space is irradiated with a sonar signal, the signals reflected from the object are received by the receiving hydroacoustic antennas spaced apart in the vertical and horizontal planes, the emission-reception of the phase difference between the pairs of signals received by the respective pairs of receiving antennas spaced apart in the horizontal and vertical planes is measured at each instant during the cycle by the phase centers in the plane of the front of the reflected signal in which measurement and accumulation are performed for some predetermined number of cycles of the sample characteristic function for some predefined set of values of the arguments, the obtained estimates of the characteristic function for the current cycle and for the predetermined number of preceding cycles are compared, and a decision is made based on the comparison results about the presence or absence of a useful signal, the value of the bearing and the angle of its source location. In addition, the comparison of the sample characteristic functions is performed by multiplying the characteristic function in the current emission cycle by the complex conjugate characteristic function averaged over the previous cycles and normalized to its modulus. In addition, to decide whether a useful signal exists, the squares of the moduli of the result of comparing the characteristic functions are averaged and the value obtained is compared with the predetermined threshold. In addition, the value of the phase of the components of the result of the comparison of the characteristic functions is used to determine the angular position. Method options and a group of devices for implementing the method are given.

EFFECT: technical result consists in the elimination of measurement errors caused by the statistical dependence of the phase difference estimates for the vertical and horizontal measurement channels, increase in the accuracy and decrease in the resource intensity by using the measurement of the characteristic function of the joint distribution of the phase difference estimates of the signals in the vertical and horizontal measurement channels.

12 cl, 5 dwg