阅读说明：本技术 一种基于多波束陷落波束偏转的宽容性声场定向调控方法 (Wide capacitive sound field directional regulation and control method based on multi-beam trapped beam deflection ) 是由 李建龙 夏永森 于 2021-07-12 设计创作，主要内容包括：本发明公开了一种基于多波束陷落波束偏转的宽容性声场定向调控方法。该方法首先进行被控制声源声场信息采集,利用采集的信息进行源声场重构；然后基于线性约束最小方差技术改进并构建目标函数,通过求解目标函数最优化问题获得调控权向量,经驾驶到主动控制源后实现声场定向调控。本发明将被控制声源视作一个发射声源,与主动控制声源组成“联合发射阵”,通过将拟抑制方向附近多个角度均设定为干扰信号方向,从而实现在该方向及相邻角度多列声波干涉下能量抑制的最大化,提升波束偏转算法的宽容性。本发明在声场调控领域具有潜在应用价值。(The invention discloses a wide-tolerance sound field directional regulation and control method based on multi-beam trapped beam deflection. Firstly, acquiring controlled sound source sound field information, and reconstructing a source sound field by using the acquired information; and then improving and constructing an objective function based on a linear constraint minimum variance technology, obtaining a regulation and control weight vector by solving an objective function optimization problem, and realizing sound field directional regulation and control after driving to an active control source. The controlled sound source is regarded as a transmitting sound source, the transmitting sound source and the active control sound source form a combined transmitting array, and a plurality of angles near the direction to be suppressed are set as the interference signal direction, so that the maximization of energy suppression under multi-row sound wave interference in the direction and the adjacent angles is realized, and the wide compatibility of a beam deflection algorithm is improved. The method has potential application value in the field of sound field regulation and control.)

1. A wide-capacitive sound field directional regulation and control method based on multi-beam collapse beam deflection is characterized in that the method is used for realizing sound energy redistribution by sound field directional regulation and control and comprises the following steps:

1) controlled sound source sound field information acquisition:

firstly, receiving a sound pressure signal of a controlled sound source through a hydrophone array arranged in a sound field acquisition area, extracting frequency, amplitude, phase information and the like of the controlled sound source according to the received information, and reconstructing the controlled sound source into s according to a point source according to near-far field sound propagation characteristics₀(t)。

2) Directional sound field multi-beam collapse regulation:

the active control sound source and the controlled sound source form a combined transmitting array. Setting the number of active control sound sources as M, and according to the position relation between each active control sound source and the reconstructed controlled sound source, under the far-field plane wave condition, expressing the array response vector of each sound source in the 'joint transmitting array' as:

wherein j is an imaginary unit, pi is a circumferential rate, superscript H is a conjugate transpose operator, and τ_m(phi) is the M (M1, 2,.., M) th actively controlled sound source at azimuth phiRelative to the time delay of the sound source being controlled.

The directional regulation and control of the sound field is realized by carrying out linear weighting on the emission signals of all active control sound sources in the 'joint emission array'. Let the weighted vector be c ═ c₀,c₁,c₂,...,c_M]^HWherein c is₀In order to control the weighting coefficients of the sound sources,weighting coefficients for the mth actively controlled source except the controlled sound source, wherein A_mFor the amplitude weight of the mth active control source, t_mThe transmission time delay of the mth active control source relative to the controlled sound source is obtained. After linear weighting, the sound pressure signal y (t) in the far field phi direction is c^Hv(φ)s₀(t)。

When wide-capacity directional regulation and control of sound field are carried out, the quasi-suppression direction phi is realized_iAnd adjacent direction phi_iThe energy minimization of +/-delta phi is realized by solving the following multi-constraint objective function optimization problem, namely:

wherein, Δ φ represents the adjacent angle range of the intended suppression direction, c₀1 means that the corresponding controlled source weight coefficient is not adjustable.

Solving the optimization problem of the formula (2), and finally determining the optimal weighting vector as follows:

wherein alpha is a constant coefficient consisting of c₀The constraint of 1 is finally determined.

Weighting the vector c obtained by the formula (3) to each active control sound source, then transmitting the signal, and forming a superposed sound field with the controlled sound source; this process is equivalent to the signal transmission of a "joint transmit array". The deflection of multi-beam trapped beams of a 'joint transmitting array' is realized by the linear weighting of an active control sound source, and the purpose of directional regulation and control of a sound field is achieved.

Technical Field

The invention belongs to the field of underwater sound field regulation and control, and particularly relates to a wide-tolerance sound field directional regulation and control method based on multi-beam collapse beam deflection.

Background

With the development of noise control technology, attention is increasingly paid to control of low-frequency and local sound fields. Part of the technologies are mature in the fields of automobile noise control, earphone active noise elimination and the like, and the research in the field of underwater stealth is concerned increasingly.

The sound field linear regulation and control technology usually achieves the purpose of weakening the local sound field intensity of a controlled sound source by presetting the amplitude, phase and frequency of an active control sound source and utilizing the sound field interference effect of the active control sound source and the controlled sound source. Because the conventional plane wave sound field interference technology cannot realize the maximization of specific direction energy suppression, the beam deflection method based on the optimal beam forming brings the problem of poor algorithm tolerance on the basis of solving the problems.

Disclosure of Invention

The invention aims to provide an improved wide-capacity sound field orientation regulation and control method based on multi-beam trapped beam deflection aiming at the defects of the prior art. The invention realizes the wide-range suppression of the sound field intensity in the specific direction of the controlled source by regulating and controlling the amplitude and the phase of the active control source based on the plane wave linear constraint minimum variance beam forming principle.

The purpose of the invention is realized by the following technical scheme: a wide-capacity sound field directional regulation and control method based on multi-beam trapped beam deflection is used for realizing sound energy redistribution by sound field directional regulation and control and comprises the following steps:

1) controlled sound source sound field information acquisition:

firstly, receiving a sound pressure signal of a controlled sound source through a hydrophone array arranged in a sound field acquisition area, extracting frequency, amplitude, phase information and the like of the controlled sound source according to the received information, and reconstructing the controlled sound source into s according to a point source according to near-far field sound propagation characteristics₀(t)。

2) Directional sound field multi-beam collapse regulation:

the active control sound source and the controlled sound source form a combined transmitting array. Setting the number of active control sound sources as M, and according to the position relation between each active control sound source and the reconstructed controlled sound source, under the far-field plane wave condition, expressing the array response vector of each sound source in the 'joint transmitting array' as:

wherein j is an imaginary unit, pi is a circumferential ratio, superscript H is a conjugate transpose operator,τ_mand (phi) is the time delay of the M (M is 1,2,.., M) th actively-controlled sound source relative to the controlled sound source when the azimuth angle phi is.

The directional regulation and control of the sound field is realized by carrying out linear weighting on the emission signals of all active control sound sources in the 'joint emission array'. Let the weighted vector be c ═ c₀,c₁,c₂,...,c_M]^HWherein c is₀In order to control the weighting coefficients of the sound sources,weighting coefficients for the mth actively controlled source except the controlled sound source, wherein A_mFor the amplitude weight of the mth active control source, t_mThe transmission time delay of the mth active control source relative to the controlled sound source is obtained. After linear weighting, the sound pressure signal y (t) in the far field phi direction is c^Hv(φ)s₀(t)。

When wide-capacity directional regulation and control of sound field are carried out, the quasi-suppression direction phi is realized_iAnd adjacent direction phi_iThe energy minimization of +/-delta phi is realized by solving the following multi-constraint objective function optimization problem, namely:

wherein, Δ φ represents the adjacent angle range of the intended suppression direction, c₀1 means that the corresponding controlled source weight coefficient is not adjustable.

Solving the optimization problem of the formula (2), and finally determining the optimal weighting vector as follows:

wherein alpha is a constant coefficient consisting of c₀The constraint of 1 is finally determined.

Weighting the vector c obtained by the formula (3) to each active control sound source, then transmitting the signal, and forming a superposed sound field with the controlled sound source; this process is equivalent to the signal transmission of a "joint transmit array". The deflection of multi-beam trapped beams of a 'joint transmitting array' is realized by the linear weighting of an active control sound source, and the purpose of directional regulation and control of a sound field is achieved.

The invention has the beneficial effects that:

1) the method is based on the principle of multi-column sound wave interference cancellation, utilizes the existing plane wave array processing technology, is simple to realize, and has important significance in the practical application fields of underwater low-frequency directional sound masking and the like;

2) the invention utilizes the beam forming technology to adjust the phase and the amplitude, and the beam depressed area can be flexibly deflected, thereby realizing the optimal cancellation of the sound field in any appointed direction;

3) the method has better tolerance in the direction of the sound field to be restrained and regulated, and can further adjust the width of the falling valley according to the actual engineering so as to flexibly balance the restraining effect and the tolerance of the algorithm.

Drawings

FIG. 1 is a schematic diagram of a sound field directional control system for implementing the method of the present invention;

FIG. 2 is a schematic diagram of the controlled sound source and the active controlled sound source arrangement of the present invention;

FIG. 3 is a schematic diagram of a sound field simulation of a controlled sound source and a composite active control sound source according to the present invention; wherein, (a) is a composite array beam pattern diagram, the sound field quasi-suppression direction is 0 degree, and the suppression angle range is +/-5 degrees; (b) sound pressure level varying with azimuth angle phi at distance 3000 m; (c) the sound pressure level of the direction phi, which is 0 DEG, as a function of distance is to be suppressed.

Detailed Description

The invention is further described below with reference to the accompanying drawings.

The invention uses the principle of plane wave optimal beam forming for inhibiting the interference in a specific direction for improvement, realizes the wide-angle directional weakening of a controlled sound field in a multi-beam collapse beam deflection mode, and achieves the purpose of simultaneously considering the minimization of the sound field intensity of the controlled sound source in the specific direction and the algorithm tolerance.

According to the principle of sound wave interference, when the phases and amplitudes of the active control sound source and the controlled sound source satisfy a certain relationship, coherent cancellation of sound waves can be realized, so that the sound field intensity of the controlled sound source is reduced in a cancellation region. If the number of the active control sound sources is increased, the regulation effect of the sound field can be further improved through interference of multiple rows of sound waves, namely wave beam regulation.

Based on the principle of linear constraint minimum variance beam forming, the invention aims the concave area of the emission beam of a 'combined emission array' formed by an active control source and a controlled source at the direction of a regulated sound field to be suppressed, thereby realizing the maximization of energy suppression under multi-row sound wave interference in the direction and adjacent angles so as to improve the tolerance of a beam deflection algorithm.

The invention utilizes the hydrophone array to collect the sound field information of the controlled sound source, extracts the frequency, amplitude and phase signal parameters of the controlled sound source, on the basis, the controlled sound source is regarded as a transmitting sound source, and forms a 'combined transmitting array' with the active control sound source, and a plurality of angles near the intended suppression direction are all set as the interference signal direction through the linear constraint minimum variance technology, thereby realizing the sound field offset under the interference of a plurality of rows of sound waves in the direction and the adjacent angles, and achieving the purposes of sound field directional regulation and control and improving algorithm tolerance.

Referring to fig. 1, the invention relates to a wide-tolerance sound field directional control method based on multi-beam trapped beam deflection, which is used for realizing sound energy redistribution by sound field directional control and comprises the following steps:

1) and acquiring sound field information of the controlled sound source.

Firstly, receiving a sound pressure signal of a controlled sound source through a hydrophone array arranged in a sound field acquisition area, extracting frequency, amplitude and phase information of the controlled sound source according to the received information, reconstructing a source sound field according to near-far field sound propagation characteristics (sound propagation model), and reconstructing the controlled sound source into s according to a point source₀(t); where t represents time.

2) And (3) directional sound field multi-beam collapse regulation.

The active control sound source and the controlled sound source form a combined transmitting array. And (2) setting a plurality of angles near the direction to be suppressed as the direction of an interference signal by using the controlled sound source sound field information extracted in the step 1), and realizing the driving of the transmitted beam by optimizing a multi-constraint objective function, thereby realizing the maximization of energy suppression under multi-column sound wave interference in the direction and adjacent angles and improving the tolerance of a beam deflection algorithm.

Assuming that the number of the active control sound sources is M, according to the position relationship between each active control sound source and the reconstructed controlled sound source, under the far-field plane wave condition, the array response vector v (Φ) of each sound source in the "joint transmitting array" can be expressed as:

wherein j is an imaginary unit, pi is a circumferential rate, superscript H is a conjugate transpose operator, and τ_mAnd (phi) is the time delay of the M (M is 1,2,.., M) th actively-controlled sound source relative to the controlled sound source when the azimuth angle phi is.

The directional regulation and control of the sound field is realized by carrying out linear weighting on the emission signals of all active control sound sources in the 'joint emission array'. Let weighting vector c be:

c＝[c₀,c₁,c₂,...,c_M]^H

wherein, c₀For the weighting coefficients of the sound source to be controlled, c_mWeighting coefficients for the mth active control source except the controlled sound source; a. the_mFor the amplitude weight of the mth active control source, t_mThe transmission time delay of the mth active control source relative to the controlled sound source is obtained. After linear weighting, the sound pressure signal y (t) in the far field phi direction is c^Hv(φ)s₀(t)。

When wide-capacity directional regulation and control of sound field are carried out, the quasi-suppression direction phi is realized_iAnd adjacent direction phi_iEnergy of +/-delta phiThe quantity minimization is realized by solving the following multi-constraint objective function optimization problem, namely:

wherein phi is_sThe included angle between the main beam emission direction of the joint emission array and the z axis is represented, namely the arrival angle of the useful signal; Δ φ represents the adjacent angular range of the intended suppression direction, c₀1 means that the corresponding controlled source weight coefficient is not adjustable.

Solving the above optimization problem can finally determine the optimal weighting vector c as:

wherein alpha is a constant coefficient consisting of c₀The constraint of 1 is finally determined.

And weighting the vector c to each active control sound source, then carrying out signal transmission, forming a superposed sound field with the controlled sound source, wherein the process can be equivalent to signal transmission of a combined transmitting array. The deflection of multi-beam trapped beams of a 'joint transmitting array' is realized by the linear weighting of an active control sound source, and the purpose of directional regulation and control of a sound field is achieved.

Examples illustrate that: in order to verify the effectiveness of the wide-capacity sound field directional regulation and control method based on the deflection of the multi-beam trapped beams, simulation analysis is carried out. Referring to FIG. 2, let the coordinates of the controlled sources be (0,100m), the active control sources are uniformly distributed at the radius R_MarrayOn the circumference of 1.6M, the number M of the active control sound sources is 7, and the frequency f in the simulation is 500 Hz.

FIG. 3(a) is a diagram of a complex array beam pattern with a pseudo-suppression direction φ_i0 ° and a suppression angle range of ± 5 °; FIG. 3(b) is the sound pressure level as a function of azimuth angle φ at a distance of 3000 m; FIG. 3(c) shows pseudo-inhibitionDirection phi_i0 ° sound pressure level as a function of distance. As can be seen from the simulation results of fig. 3(b) and 3(c), the weakening effect of the sound field intensity of the controlled sound source in the intended suppression direction and the intended suppression adjacent angle range is above 20dB, which illustrates the effectiveness of the wide-capacitive sound field directional control method based on the deflection of the multi-beam trapped beams.

The embodiments described in this specification are merely illustrative of implementations of the inventive concept and the scope of the present invention should not be considered limited to the specific forms set forth in the embodiments but rather by the equivalents thereof as may occur to those skilled in the art upon consideration of the present inventive concept.