Positioning and velocity measuring method and device for underwater target in unknow sound velocity environment

Abstract

The invention discloses positioning and velocity measuring method and device for an underwater target in an unknow sound velocity environment. The positioning and velocity measuring method specifically includes: (1) placing transceiving duplexing array elements and the underwater target, and emitting a detect signal; (2) by the aid of the array elements, receiving and detecting echoes reflected back after reaching the target; (3) seeking real-time velocity speed of a detecting path; (4) seeking coordinates of the target in various dimensions, and integrating the coordinates to obtain a real-time three-dimensional coordinate of the target; (5) measuring velocity of the target according to doppler shift. Compared with an existing underwater sound positioning technology in which inaccurate sound velocity measurement results to larger positioning error, the positioning and velocity measuring method and device have the advantages that a theoretically feasible real-time sound velocity measuring method is provided by an algorithm on the basis of angle characteristic relations between the array elements and the target, the sound velocity in the target detecting path can be determined accurately in real time, and great significance to improvement of positioning accuracy of the underwater sound positioning technology is realized.

Description

Technical field [0001] The invention relates to the field of positioning and speed measurement of underwater targets, in particular to an underwater target positioning and speed measurement method and device used in an environment with unknown sound speed. Background technique [0002] The underwater acoustic positioning system is a typical sonar system, which can be used to accurately locate, navigate, detect and identify targets in a specific area under water. According to the difference of the baseline length of the receiving array, the underwater acoustic positioning system can be divided into a long baseline positioning system, a short baseline positioning system and an ultra-short baseline positioning system. The ultra-short baseline underwater acoustic positioning system is a positioning method based on signal phase difference estimation. It requires that the distance between the receivers be less than half of the signal wavelength. The size of the base array is very small...

AI Technical Summary

Problems solved by technology

Although the direct method and the indirect method are simple in principle and convenient to operate, they both need to measure the sound velocity on a certain detection path when the target position is known, and in underwater target positioning, the target position is unknown And it is used for estimation; at the same time, the indirect method can only measure the average speed of sound in a certain sea area. For a seawater environment with uneven sound speed distribution, its measurement error will increase significantly

Images