Variable norm equivalent source near-field acoustical holography algorithm with sound source sparseness adaptability

Abstract

The invention discloses a variable norm equivalent source near-field acoustical holography algorithm with sound source sparseness adaptability. The algorithm comprises the following steps: arranging a holographic surface in a sound source near-field radiation area, and measuring to obtain sound pressure PH on the holographic surface; arranging an equivalent source surface on one side, away from the holographic surface, of a target reconstruction surface; establishing a relationship between the sound pressure and an equivalent source by using a sound pressure transfer matrix between the equivalent source and the holographic surface; and solving the source intensity of the equivalent source by adopting an iterative regularization algorithm with a self-adaptive norm constraint penalty term, and calculating by using the obtained source intensity and a transfer matrix between the equivalent source and the target reconstruction surface to obtain sound field data on the target reconstruction surface. According to the method, the p value in an lp norm penalty term in the regularization solving process is adaptively changed, so that the sparseness of the source intensity of the equivalent source obtained through solving is more consistent with the actual sparseness of the sound source, and accurate solving can be achieved for a space sparse sound source, a space continuous sound source or a sound source with the source intensity sparseness between sufficient sparseness and continuity.

Description

technical field [0001] The invention relates to the field of noise source identification, in particular to a variable-norm equivalent source near-field acoustic holography algorithm with adaptive sound source sparsity. Background technique [0002] Near-field acoustic holography technology is a powerful tool for sound source identification and sound field visualization. The holographic transformation algorithm is the core part of near-field acoustic holography. The spatial Fourier transform method and statistical optimal algorithm, as well as a variety of near-field acoustic holography algorithms such as the boundary element method and equivalent source method suitable for sound sources of arbitrary shape. Among them, the equivalent source method can be used for the reconstruction and prediction of the radiated sound field of objects with arbitrary shapes, and avoids the non-uniqueness of the solution at the characteristic frequency in BEM, overcomes the singular integral pr...

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Problems solved by technology

This method uses l when solving the source strength 1 The norm constraint penalty term makes the obtained result always lead to a sparse solution, so this method has higher reconstruction accuracy when dealing with spatially sparse sound sources, but cannot obtain higher reconstruction accuracy when dealing with spatially continuous sound sources Near-field acoustic holography calculation results of

However, in practical applications, there are not only spatially continuous sound sources and spatially sparse sound sources, but also a large number of sound sources whose sparsity is between the two. Since the above two methods use fixed norms, there is no sound source Different adjustments to the actual sparsity of the penalty term used in the regularization method cannot match the actual sparsity of this type of sound source well to obtain accurate reconstruction results. It can be seen that the above two methods have the flexibility of the solution process Poor performance and low universality

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