Method for measuring distance of low-frequency underwater sound pulse signal on basis of frequency dispersion features

Abstract

The invention discloses a method for measuring a distance of a low-frequency underwater sound pulse signal on the basis of frequency dispersion features, which comprises the following steps of: a step 10 of receiving the low-frequency underwater sound pulse signal by a single hydrophone and then carrying out representation of time-frequency distribution with a self-adaption radial gaussian kernel function on the frequency dispersion features of the low-frequency underwater sound pulse signal; a step 20 of extracting a frequency dispersion curve of spread modes in the time-frequency distribution to obtain a time difference of arrival between the modes; and a step 30 of measuring the distance of a sound source according to the time difference between the extracted modes under each frequency point, i.e. firstly, measuring theoretical group velocity values corresponding to the extracted modes under each frequency point by using a normal mode model, then estimating the distance of the sound source under each frequency point in a frequency range in which a mode mc is the same with a mode nc, and finally, measuring an arithmetic mean of the estimated distances under all the frequency points so as to obtain the distance of the sound source. According to the measuring method, accurate measurement on the distance of the low-frequency underwater sound pulse signal of shallow sea can be implemented by utilizing the single hydrophone.

Description

technical field [0001] The invention relates to a method for measuring the distance of an underwater target in the technical field of underwater acoustic signal processing, in particular to a method for measuring the distance of a low-frequency underwater acoustic pulse signal based on dispersion characteristics. Background technique [0002] Determining the distance of underwater targets plays an extremely important role in underwater acoustic technology. It is an important and basic problem in underwater acoustic technology, and it is also a key technology for national economic construction and national defense construction. The traditional underwater acoustic ranging technology generally adopts an array processing method with a large aperture to obtain good array gain and resolution performance. However, using a large array with multiple array elements increases the cost of the system and brings inconvenience to the design of the array. In addition, in some applications,...

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Problems solved by technology

Traditional time-frequency analysis methods such as the short-time Fourier transform based on linear time-frequency representation are affected by the uncertainty principle, and their time-frequency resolution is low; while the Wegener-Willi distribution based on quadratic time-frequency representation There are serious cross-item interference problems

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