Method for identifying non-stable acoustic source characteristics by bias coherent technology

A non-stationary sound source and characteristic technology, applied in the field of identifying sound source characteristics, can solve problems that have not yet been discovered

Inactive Publication Date: 2005-05-18
SHANGHAI JIAOTONG UNIV
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Problems solved by technology

In further searches, no literature reports identical or similar to the subject of the present invention have been found

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  • Method for identifying non-stable acoustic source characteristics by bias coherent technology
  • Method for identifying non-stable acoustic source characteristics by bias coherent technology
  • Method for identifying non-stable acoustic source characteristics by bias coherent technology

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Embodiment Construction

[0019] The following examples are provided in conjunction with the method content of the present invention:

[0020] 1. Assuming that the number and location of sound sources are known, two speakers are used to generate sound to form two cyclostationary sound sources, and two microphones are arranged to extract reference source signals.

[0021] The excitation source for the loudspeaker is:

[0022] Vsourcel=Acos(2πf 1 t)*noise(t)

[0023] Vsource2=B(1+Ccos(2πf b t))*cos(2πf a t)

[0024] Among them, A=10, B=C=1, f1=300, f a =300,f b =120, noise is band-pass colored noise.

[0025] 2. Arrange 25 microphones in a linear array, scan and measure the entire holographic surface to form a 25×25 holographic surface array; while collecting data on the holographic surface, use two reference source microphones to collect reference source sound signals. During measurement, the acoustic signals of all microphone channels are collected synchronously, and the records are stored in a...

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Abstract

A method for identifying non-stationary sound source characteristics using partial coherence technology belongs to the field of noise in physics. In the case where multiple sound sources generate complex cyclostationary sound fields, the present invention adopts cyclostationary theory instead of Fourier transform, proposes a partial coherence analysis technology suitable for cyclostationary sound fields, and uses it in the partial sound field separation of cyclostationary sound fields, the method As follows: first determine the number and location of the reference source, arrange the reference source microphone array, extract the reference source signal, then design the microphone array to scan and measure the holographic surface, collect the holographic surface data, and then use the cyclostationary partial coherence analysis technology to separate Part of the sound field for each sound source. The present invention can analyze the complex cyclostationary sound field formed by multiple cyclostationary sound sources, obtain the partial sound field formed by each sound source, and also calculate the three-dimensional sound field formed by a single sound source from the sound pressure signal measured on the holographic plane. The sound field distribution realizes the visualization of the propagation path of each sound source.

Description

technical field [0001] The invention relates to a method for identifying the characteristics of a sound source, in particular to a method for identifying the characteristics of a non-stationary sound source using the partial coherent partial sound field separation technology of a cyclostationary sound field, which belongs to the field of noise in the physics category. Background technique [0002] Understanding the characteristics of noise sources is the premise of noise control. Therefore, in order to effectively control noise, before noise reduction measures are implemented, noise source diagnosis must be carried out first to determine the location and characteristics of major noise sources. With the development of modern signal processing technology, spectral analysis technology, coherent and partial coherent analysis technology, sound intensity analysis technology and acoustic near-field holography technology have been developed rapidly. After literature search, M.A. Tom...

Claims

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Application Information

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Patent Type & Authority Patents(China)
IPC IPC(8): G01H17/00
Inventor 蒋伟康万泉
Owner SHANGHAI JIAOTONG UNIV
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