METHOD FOR DETECTING MOVING TARGETS BY SONAR AND DEVICE TO THIS END Russian patent published in 2009 - IPC G01S15/12 

FIELD: physics.

SUBSTANCE: present invention relates to the field of hydroacoustics and can be used for acoustic monitoring of oceans, seas and inland water bodies with the aim of intruder detection in the economic zone of the country etc. The method of detecting moving targets in a hydrolocation lies in sequential irradiation of the controlled region of the water area of the ocean with acoustic pulses, reception of scattered object and distorted pulses, algorithmic cooperative processing of sent and received signals. In the limits of one transmitted pulse the periodic law of frequency modulation is used, the signal received is compressed in the filter, matched with one period of intra-pulse frequency modulation; the compressed signal is then transformed by a delay for a period of intra-pulse modulation and removing the delayed signal from its non-delayed copy. Transforming the compressed signal is subjected to coherent integration for a period as long as the transmitted pulse taking into account the expected values of time of arrival of the reflected signal and Doppler frequency of the target located, the accumulated enveloping signal is separated, a set of enveloping ones is formed for different values of time of arrival and Doppler frequencies and by the formed sets we get information about the presence and character of moving targets using known and/or special algorithms.

EFFECT: decrease in detection time.

2 cl, 1 dwg