CN103616071A - Three-dimensional distribution visualization method for Patch near-field acoustical holography and sound quality objective parameters - Google Patents

Abstract

The invention discloses a three-dimensional distribution visualization method for sound quality objective parameters based on a Patch near-field acoustical holography technology. According to the method, frequent scanning measurement is carried out on the surface of a large-scale complex sound source by means of a small microphone array in a sound field formed by large-scale structured sound source radiation, wherein incoming waves and outgoing waves exist in the sound field; the distribution information of acoustic quantities and sound quality objective parameters in the whole space sound field can be obtained through a Patch near-field acoustical holography and sound quality coupling matrix calculation model, and therefore the three-dimensional distribution visualization for the acoustics physical quantities and the sound quality objective parameters can be achieved.

Description

The objective parameter distributed in three dimensions of Patch near field acoustic holography-sound quality method for visualizing

Technical field:

The present invention relates to large and complex structure Noise Sources Identification location technology and sound quality evaluation, say more specifically the objective parameter distributed in three dimensions of the sound quality method for visualizing based on Patch near field acoustic holography theory.

Background technology:

Near field acoustic holography method NAH (Near field Acoustic Holography) is the acoustics near-field information that utilizes the holographic measurement face near sound source to obtain, and reconstructs the method for the sound field physical message (acoustic pressure, vibration velocity etc.) in three dimensions by various mathematic(al) manipulations.NAH method captures the evanescent wave in sound field by near field measurement, obtains the vibration details of object, can obtain in theory the high resolving power that is not subject to wavelength X restriction, has greatly improved the precision of identification of sound source location.At present, NAH method has been widely used in the identification and location of sound source, the occasions such as acoustic radiation measurement that the characteristic that is particularly useful for low-frequency sound source is differentiated, acoustic scattering measurement and structural vibration cause.But it is at least more than the twice of sound source area that conventional near field acoustic holography method requires microphone array to measure aperture.Therefore, if measure and analyze large scale and labyrinth sound source, just need to configure a large amount of microphones, make to measure required equipment price expensive.For example, to 0.4 * 0.6m ²the plate sound source of size adopts Fourier transform near field acoustic holography algorithm reconstruct radiated sound field under 40dB signal to noise ratio (S/N ratio) condition, if obtain 0.05m resolution, need to adopt 882 microphones to measure, this substantially cannot realize in actual measurement of engineering, and number of microphone has limited near field acoustic holography method applying in occasions such as large and complex structure sound source measurements.

And Patch near field acoustic holography algorithm well overcomes this problem.It is by being decomposed into a plurality of local sound sources by large scale and labyrinth sound source, adopt same microphone array to carry out successively scanning survey to each local sound source, by the composition algorithm reconstruct of Patch acoustical holography aperture, obtain the space distribution of the acoustics amount of whole sound source, broken through conventional near field acoustic holography for the restriction in holographic measurement aperture.

On the other hand, researchist finds that noise is not only relevant with sound pressure level for people's impact, also relevant with the composition of sound self frequency, human auditory system's physical characteristics and people's psychological characteristic.Two kinds of sound of same sound pressure level are due to the difference that frequency separately forms, and can cause the greatest differences of loudness sensuously human psychological.Therefore need to introduce can reflect people to sound subjective feeling Liang sound quality, as the reference to noise rating.The sound quality that Blauet provides is defined as: " sound quality " refers to that people passes through the Auditory Perception of people's ear to sound event, in the subjective process of making hobby judgement.And the description of sound quality quality can be by series reaction in the subjective mood of noise on human the index (as sharpness, roughness, loudness etc.) of influence degree represent.

In sum, by near field acoustic holography method, come computational analysis noise can provide the space distribution of the acoustics amounts such as acoustic pressure, the sound intensity, but the analytic process of near field acoustic holography method is not taken people's subjective feeling into account, result of calculation does not provide the spatial distribution result of the objective parameters of sound quality such as loudness, sharpness, can not realize the have the greatest impact location of sound source position of the subjective auditory perception of people.And existing sound Quality Analysis Methods is all the sound field information recording for several microphones, calculates, analyze and evaluate, use existing sound Quality Analysis Methods can only obtain the objective parameter information of sound quality of this local test point position, space, can not be as the evaluation criterion of whole spatial sound quality quality, do not reflect people's subjective auditory perception and the mutual relationship between noise source space distribution, cannot obtain the sound source position information that the subjective auditory perception of people is had the greatest impact.

Seminar is the sound quality distributed in three dimensions method for visualizing based on sphere near field acoustic holography method of research and development (application number: the preliminary identification location that 201310261258.2) is mainly used in the sound sources such as enclosure space sound field (as automobile bodies inside) previously.Under identical microphone quantity and identical sound field condition, the auditory localization precision of sphere near field acoustic holography method does not have the precision of Patch acoustical holography method high.Patch acoustical holography can not be for the noise source location of narrow and small enclosure space inside simultaneously, and the physical model of the Reconstruction of Sound Field of two kinds of methods and mathematical formulae are all different, are to be applied to the distinct methods that dissimilar acoustic field is analyzed.

Therefore, the present invention propose a kind of based on Patch near field acoustic holography harmony quality associating (Patch Near field Acoustic Holography Sound Quality, Patch NAH SQ) analytical approach.The method has broken through conventional near field acoustic holography for the restriction in holographic measurement aperture, the space distribution of the objective parameter of sound quality that can realize large scale and labyrinth sound source is visual, disclosed the mutual relationship between subjective auditory perception and large and complex structure distribution of noise sources, and hi-Fix has gone out the position at the noise source place the closest with people's auditory perception.

Summary of the invention:

The present invention will overcome the restriction in acoustical holography array measurement aperture, realize Measurement and analysis and the location of large and complex structure sound source, and can not provide the objective parameter distributed intelligence of sound quality in whole space when the objective Parameters Calculation of use sound quality is evaluated sound field separately, and the defect of not considering people's subjective sense of hearing factor while adopting separately the field distribution of near field acoustic holography methods analyst spatial sound, realize according to the object of people's subjective auditory perception identification location noise source.

The present invention proposes a kind of distributed in three dimensions method for visualizing of the objective parameter of sound quality based on Patch near field acoustic holography method, its result of calculation has realized the visual of whole large and complex structure sound source surface and the interior Middle and low frequency noise of radiated sound field thereof, the distributed in three dimensions information of the objective parameter of sound quality is provided, and provide the noise source positional information that affects the subjective auditory perception maximum of people, thereby for providing the most directly, the vibration and noise reducing of large scale structure instructs.

The three-dimensional visualization method of the objective parameter of sound quality based on Patch near field acoustic holography method of the present invention carries out as follows:

1. adopt same small size high density microphone array to carry out repeatedly near-field scan to large and complex structure sound source and measure, obtain the near field acoustical signal information of whole sound source face.In each measurement, record reference point locations signal, as each witness mark signal.

2. according to the 1 near field acoustical signal information measuring, first by carrying out dry calculating mutually with reference microphone signal, obtain the multiple sound pressure signal of the synchronous microphone of all measurement faces, then adopt Patch near field acoustic holography method to obtain the three-dimensional spatial distribution information (acoustic pressure, particle rapidity etc.) of sound field acoustics amount, result of calculation provides with the form of 3D rendering.

The acoustic pressure of Patch near field acoustic holography method definition different measuring face is calculated with following formula:

Complex pressure phase: $\mathrm{\θ}\left(\mathrm{\ω}\right)=\arg \left[\frac{S_{r,h}\left(\mathrm{\ω}\right)}{S_{r,r}\left(\mathrm{\ω}\right)}\right]---\left(1\right)$

Multiple sound pressure amplitude: $p\left(\mathrm{\ω}\right)=\sqrt{S_{h,h}\left(\mathrm{\ω}\right)}---\left(2\right)$

Multiple acoustic pressure size: p (r)=p (ω) e ^{j θ (ω)}(3)

In formula: S representative is relevant calculates, subscript r, h represents microphone signal on reference point and array measurement face.

The sound field transformation for mula of reconstruct face is as follows:

p(r)=p ^T(A ⁺A+θ ²I) ^-1A ⁺α (4)

A in formula ⁺a and A ⁺α is determined by following formula:

${\left[A^{+}A\right]}_{{\mathrm{nn}}^{\′}}=\frac{1}{{\mathrm{\πk}}^2}{\∫\∫}_{-\∞}^{\∞}{e}^{j(k_z^{*}-k_z)d}{e}^{-j{K}_{\mathrm{xy}}(r_{\mathrm{xy},n}-r_{\mathrm{xy},n^{\′}})}{\mathrm{dk}}_x{\mathrm{dk}}_y---\left(5\right)$

${\left[A^{+}\mathrm{\α}\right]}_n=\frac{1}{{\mathrm{\πk}}^2}{\∫\∫}_{-\∞}^{\∞}{e}^{j(k_z^{*}d-k_{z}z)}{e}^{-j{K}_{\mathrm{xy}}\left(r_{\mathrm{xy}}{-r}_{\mathrm{xy},n}\right)}{\mathrm{dk}}_x{\mathrm{dk}}_y---\left(6\right)$

In formula: p is the column vector that the acoustic pressure of all measurement points on measurement face forms, p ^ttransposition for p; R is the Cartesian coordinates of any reconstruction point in space, r=(x, y, z), the acoustic pressure that p (r) is reconstruction point; K is wave number, k _zfor the space wave number in z direction on reconstruction face, * represents complex conjugate; K _xy=(k _x, k _y), k _xfor the space wave number in x direction on reconstruction face, k _yfor the space wave number in y direction on reconstruction face; r _xy=(x, y) is the xy coordinate of reconstruction point, r _{xy, n}=(xn, yn), r _{xy, n '}=(x _{n '}, y _{n '}), r _{xy, n}and r _{xy, n '}the xy coordinate that represents respectively microphone measurement point n and n '; D is that measurement face is to the distance of sound source face.

3. according to the model for coupling of sound field information and the objective parametric algorithm of sound quality in the sound field information in the space obtaining in 2 (acoustic pressure, particle rapidity etc.) and space disclosed by the invention, obtain sound quality information (as loudness, sharpness etc.) the distributed in three dimensions information of position, space, the distributed in three dimensions that realizes the objective parameter of sound quality is visual, and identifies accordingly the position with the closely related sound source of the subjective auditory perception of people.

The computation model of sound quality loudness: according to the loudness definition of Moore, the loudness of the objective parameter of psychologic acoustics is calculated and be take ERB (Equivalent Rectangular Width-equivalent rectangular width) yardstick as basis, in the auditory frequency range of people's ear 0.05kHz～15kHz, set up 372 auditory filters, wherein the corresponding relation of critical band width ERB and frequency f (kHz) can be approximately:

ERB=24.673(0.004368f+1) (7)

In formula: the centre frequency that f is bandwidth.

In 0.05kHz～15kHz frequency range, the centre frequency of human auditory system wave filter can be obtained by following formula:

ERB-number=21.366lg(0.004368f+1) (8)

In formula: the centre frequency that f is wave filter.

And the output drive of wave filter can be tried to achieve by following formula:

$E_i=\frac{\mathrm{\&Sigma;W}\left(g_{\mathrm{ij}}\right)P_j^2}{{\mathrm{<figure-callout\; id="0"\; label="P"\; filenames="HDA0000432951380000011.png"\; state="\{\{state\}\}">P</figure-callout>}}_0^2}{E}_0---\left(9\right)$

In formula: E _ibe the output drive of i wave filter, W (g _ij) be the response of i wave filter to the input of frequency j place,

for the effective value power of input signal, P ₀for reference sound pressure 2 * 10 ^-5handkerchief.Obtaining on filter output signal basis, can try to achieve characteristic loudness N'.

Final loudness is the characteristic loudness sum that 372 wave filters are tried to achieve, as shown in the formula:

$N=\underset{i=1}{\overset{372}{\mathrm{\&Sigma;}}}{N}_i^{\&prime;}---\left(10\right)$

Sharpness model: in sharpness computation process, sharpness represents with S, and its computing formula is:

$S=0.1043\&times;\frac{{\&Integral;}_0^{24}{N}^{\&prime;}g\left(z\right)\mathrm{dz}}{{\&Integral;}_0^{24}{N}^{\&prime;}\mathrm{dz}}---\left(11\right)$

In formula: N' is the characteristic loudness in Zwicker Scale Model of Loudness, and

$g\left(z\right)=\left\{\begin{array}{cc}1& (z<16)\\ 0.066e^{0.171z}& (z\&GreaterEqual;16)\end{array}\right.---\left(12\right)$

According to the spatial distribution result of acoustic pressure in the sound field calculating in 2, and in conjunction with the computation model of the objective parameter of single-point sound quality in space, set up the coupling three-dimensional matrice mapping model of sonic pressure field and loudness field in space, that is:

${{[p(x,y,z,{\mathrm{\&omega;}}_1)\&CenterDot;\&CenterDot;p(x,y,z,{\mathrm{\&omega;}}_m)]}_{1\&times;m}\left[\begin{array}{ccc}{w}_1& \&CenterDot;\&CenterDot;& w_{372}\\ w_1& \&CenterDot;\&CenterDot;& w_{372}\\ \&CenterDot;& \&CenterDot;\&CenterDot;& \&CenterDot;\\ w_1& \&CenterDot;\&CenterDot;& w_{372}\end{array}\right]}_{m\&times;372}={[{\mathrm{<figure-callout\; id="1"\; label="N"\; filenames="HDA0000432951380000012.png"\; state="\{\{state\}\}">N</figure-callout>}}_1^{\&prime;}(x,y,z)\&CenterDot;\&CenterDot;N_{372}^{\&prime;}(x,y,z)]}_{1\&times;372}---\left(13\right)$

Or be abbreviated as:

P _iin W=N ' (14) formula: p _ifor the acoustic pressure under certain arbitrary frequency in location point place in sound field, P _ifor the vector that the acoustic pressure reconstruction value under each frequency of certain position in sound field forms, W is by 372 wave filter w _ithe auditory filter matrix forming, represents the response of people's ear to all frequencies in audio-band, and N ' is characteristic loudness vector.By formula (10), to the every summation in characteristic loudness vector N ', just can obtain the loudness of sound field specified point, and sound field three dimensions node is repeated to this computation process, just can obtain sound field loudness distributed in three dimensions result.The objective parameter distributed in three dimensions of other sound quality result also can adopt with loudness and calculate similar analysis process acquisition.

By said method, can calculate the objective value of consult volume of sound quality of each position of sound field, and provide its space distribution with 3-D view form, the space distribution that has realized the objective parameter of sound quality is visual, identifies the noise source that the subjective auditory perception of people is had the greatest impact.

Compare beneficial effect of the present invention with conventional art:

1. the present invention carries out repeatedly near-field scan by Miniature high-density array surface to large and complex structure sound source and measures, and breaks through the restriction of original near field acoustic holography array aperture, realizes the reconstruct of large and complex structure sound field.

2. the present invention can obtain the high precision Reconstruction of Sound Field result that is not subject to wave length of sound restriction, and can obtain all sound field information containing particle vibration velocity, sound intensity distributed in three dimensions result etc.

3. compare with existing sound quality spot measurement technology, the present invention by Miniature high-density array surface repeatedly near-field scan measure, provide the three-dimensional spatial distribution figure of the objective parameter of sound quality in whole space, make slip-stick artist can " see " space distribution of the objective parameter of sound quality.

4. the present invention can identify the noise source positional information in large and complex structure sound source, the subjective auditory perception of people being had the greatest impact, for the work of large scale structure vibration and noise reducing provides direct guidance.

Accompanying drawing explanation:

Fig. 1 small-bore plane microphone array schematic diagram

Fig. 2 microphone array is measured and is arranged and double sound source sound field schematic diagram

The loudness of Fig. 3 (a) sound source 1 (800Hz, 79dB) and two point sound source sound fields of sound source 2 (1000Hz, 84dB) and the contrast of acoustic pressure result of calculation

The sharpness of Fig. 3 (b) sound source 1 (800Hz, 79dB) and two point sound source sound fields of sound source 2 (1000Hz, 84dB) and the contrast of acoustic pressure result of calculation

The loudness of Fig. 4 (a) sound source 1 (800Hz, 82dB) and sound source 2 (1000Hz, 84dB) two point sound source sound fields and the contrast of acoustic pressure result of calculation

The sharpness of Fig. 4 (b) sound source 1 (800Hz, 82dB) and sound source 2 (1000Hz, 84dB) two point sound source sound fields and the contrast of acoustic pressure result of calculation

Embodiment:

With reference to accompanying drawing:

The present invention carries out as follows:

1. adopt same small size high density microphone array to carry out repeatedly near-field scan to large and complex structure sound source and measure, obtain the near field acoustical signal information of whole sound source face.In each measurement, record reference point locations signal, as each witness mark signal.

2. according to the 1 near field acoustical signal information measuring, first by carrying out dry calculating mutually with reference microphone signal, obtain the multiple sound pressure signal of the synchronous microphone of all measurement faces, then adopt Patch near field acoustic holography method to obtain the three-dimensional spatial distribution information (acoustic pressure, particle rapidity etc.) of sound field acoustics amount, result of calculation provides with the form of 3D rendering.

The acoustic pressure of Patch near field acoustic holography method definition different measuring face is calculated with following formula:

Complex pressure phase: $\mathrm{\&theta;}\left(\mathrm{\&omega;}\right)=\arg \left[\frac{S_{r,h}\left(\mathrm{\&omega;}\right)}{S_{r,r}\left(\mathrm{\&omega;}\right)}\right]---\left(15\right)$

Multiple sound pressure amplitude: $p\left(\mathrm{\&omega;}\right)=\sqrt{S_{h,h}\left(\mathrm{\&omega;}\right)}---\left(16\right)$

Multiple acoustic pressure size: p (r)=p (ω) e ^{j θ (ω)}(17) in formula: S representative is relevant calculates, subscript r, h represents microphone signal on reference point and array measurement face.

The sound field transformation for mula of reconstruct face is as follows:

p(r)=p ^T(A ⁺A+θ ²I) ^-1A ⁺α (18)

A in formula ⁺a and A ⁺α is determined by following formula:

In formula: S representative is relevant calculates, subscript r, h represents microphone signal on reference point and array measurement face.

${\left[A^{+}A\right]}_{{\mathrm{nn}}^{\&prime;}}=\frac{1}{{\mathrm{\&pi;k}}^2}{\&Integral;\&Integral;}_{-\&infin;}^{\&infin;}{e}^{j(k_z^{*}-k_z)d}{e}^{-j{K}_{\mathrm{xy}}(r_{\mathrm{xy},n}-r_{\mathrm{xy},n^{\&prime;}})}{\mathrm{dk}}_x{\mathrm{dk}}_y---\left(19\right)$

${\left[A^{+}\mathrm{\&alpha;}\right]}_n=\frac{1}{{\mathrm{\&pi;k}}^2}{\&Integral;\&Integral;}_{-\&infin;}^{\&infin;}{e}^{j(k_z^{*}d-k_{z}z)}{e}^{-j{K}_{\mathrm{xy}}\left(r_{\mathrm{xy}}{-r}_{\mathrm{xy},n}\right)}{\mathrm{dk}}_x{\mathrm{dk}}_y---\left(20\right)$

In formula: p is the column vector that the acoustic pressure of all measurement points on measurement face forms, p ^ttransposition for p; R is the Cartesian coordinates of any reconstruction point in space, r=(x, y, z), the acoustic pressure that p (r) is reconstruction point; K is wave number, k _zfor the space wave number in z direction on reconstruction face, * represents complex conjugate; K _xy=(k _x, k _y), k _xfor the space wave number in x direction on reconstruction face, k _yfor the space wave number in y direction on reconstruction face; r _xy=(x, y) is the xy coordinate of reconstruction point, r _{xy, n}=(x _n, y _n), r _{xy, n '}=(x _{n '}, y _{n '}), r _{xy, n}and r _{xy, n '}the xy coordinate that represents respectively microphone measurement point n and n '; D is that measurement face is to the distance of sound source face.

3 according to the model for coupling of sound field information and the objective parametric algorithm of sound quality in the sound field information in the space obtaining in 2 (acoustic pressure, particle rapidity etc.) and space disclosed by the invention, obtain sound quality information (as loudness, sharpness etc.) the distributed in three dimensions information of position, space, the distributed in three dimensions that realizes the objective parameter of sound quality is visual, and identifies accordingly the position with the closely related sound source of the subjective auditory perception of people.

The computation model of sound quality loudness: according to the loudness definition of Moore, the loudness of the objective parameter of psychologic acoustics is calculated and be take ERB (Equivalent Rectangular Width-equivalent rectangular width) yardstick as basis, in the auditory frequency range of people's ear 0.05kHz～15kHz, set up 372 auditory filters, wherein the corresponding relation of critical band width ERB and frequency f (kHz) can be approximately:

ERB=24.673(0.004368f+1) (21)

In formula: the centre frequency that f is bandwidth.

In 0.05kHz～15kHz frequency range, the centre frequency of human auditory system wave filter can be obtained by following formula:

ERB-number=21.366lg(0.004368f+1) (22)

In formula: the centre frequency that f is wave filter.

And the output drive of wave filter can be tried to achieve by following formula:

$E_i=\frac{\mathrm{\&Sigma;W}\left(g_{\mathrm{ij}}\right)P_j^2}{{\mathrm{<figure-callout\; id="0"\; label="P"\; filenames="HDA0000432951380000011.png"\; state="\{\{state\}\}">P</figure-callout>}}_0^2}{E}_0---\left(23\right)$

In formula: E _ibe the output drive of i wave filter, W (g _ij) be the response of i wave filter to the input of frequency j place,

for the effective value power of input signal, P ₀for reference sound pressure 2 * 10 ^-5handkerchief.Obtaining on filter output signal basis, can try to achieve characteristic loudness N'.

Final loudness is the characteristic loudness sum that 372 wave filters are tried to achieve, as shown in the formula:

$N=\underset{i=1}{\overset{372}{\mathrm{\&Sigma;}}}{N}_i^{\&prime;}---\left(24\right)$

Sharpness model: in sharpness computation process, sharpness represents with S, and its computing formula is:

$S=0.1043\&times;\frac{{\&Integral;}_0^{24}{N}^{\&prime;}g\left(z\right)\mathrm{dz}}{{\&Integral;}_0^{24}{N}^{\&prime;}\mathrm{dz}}---\left(25\right)$

In formula: N' is the characteristic loudness in Zwicker Scale Model of Loudness, and

$g\left(z\right)=\left\{\begin{array}{cc}1& (z<16)\\ 0.066e^{0.171z}& (z\&GreaterEqual;16)\end{array}\right.---\left(26\right)$

According to the spatial distribution result of acoustic pressure in the sound field calculating in b, and in conjunction with the computation model of the objective parameter of single-point sound quality in space, set up the coupling three-dimensional matrice mapping model of sonic pressure field and loudness field in space, that is:

${{[p(x,y,z,{\mathrm{\&omega;}}_1)\&CenterDot;\&CenterDot;p(x,y,z,{\mathrm{\&omega;}}_m)]}_{1\&times;m}\left[\begin{array}{ccc}{\mathrm{<figure-callout\; id="1"\; label="w"\; filenames="HDA0000432951380000012.png"\; state="\{\{state\}\}">w</figure-callout>}}_1& \&CenterDot;\&CenterDot;& w_{372}\\ {\mathrm{<figure-callout\; id="1"\; label="w"\; filenames="HDA0000432951380000012.png"\; state="\{\{state\}\}">w</figure-callout>}}_1& \&CenterDot;\&CenterDot;& w_{372}\\ \&CenterDot;& \&CenterDot;\&CenterDot;& \&CenterDot;\\ {\mathrm{<figure-callout\; id="1"\; label="w"\; filenames="HDA0000432951380000012.png"\; state="\{\{state\}\}">w</figure-callout>}}_1& \&CenterDot;\&CenterDot;& w_{372}\end{array}\right]}_{m\&times;372}={[{\mathrm{<figure-callout\; id="1"\; label="N"\; filenames="HDA0000432951380000012.png"\; state="\{\{state\}\}">N</figure-callout>}}_1^{\&prime;}(x,y,z)\&CenterDot;\&CenterDot;N_{372}^{\&prime;}(x,y,z)]}_{1\&times;372}$

(27)

Or be abbreviated as:

P _iin W=N ' (28) formula: p _ifor the acoustic pressure under certain arbitrary frequency in location point place in sound field, P _ifor the vector that the acoustic pressure reconstruction value under each frequency of certain position in sound field forms, W is by 372 wave filter w _ithe auditory filter matrix forming, represents the response of people's ear to all frequencies in audio-band, and N ' is characteristic loudness vector.By formula (24), to the every summation in characteristic loudness vector N ', just can obtain the loudness of sound field specified point, and sound field three dimensions node is repeated to this computation process, just can obtain sound field loudness distributed in three dimensions result.The objective parameter distributed in three dimensions of other sound quality result also can adopt with loudness and calculate similar analysis process acquisition.

By said method, can calculate the objective value of consult volume of sound quality of each position of sound field, and provide its space distribution with 3-D view form, the space distribution that has realized the objective parameter of sound quality is visual, identifies the noise source that the subjective auditory perception of people is had the greatest impact.

Below by specific embodiment, the invention will be further described.

In the present embodiment, all using small-bore plane microphone array as measuring battle array, as shown in Figure 1, plane microphone array lists and is uniformly distributed 64 microphones, and the spacing between microphone equates for 0.03m, array aperture 0.21m * 0.21m.

1. in space, arrange two monopole point sound sources: the parameter of target sound source 1 is set to 800Hz, 79dB, be placed on the negative semiaxis of x of rectangular coordinate system in space the (of 0.12m place 0.12m, 0,0); The parameter of target sound source 2 is set to 1000Hz, 84dB, is placed on 0.12m place (0.12m, 0,0) in the x positive axis of rectangular coordinate system in space, as shown in Figure 2.Distance between two sound sources is 0.24m, and plane microphone array aperture is 0.21m, and obviously sound source spacing is greater than array aperture.Patch measures identity distance from sound source face 0.06m, and the border of two Patch measurement faces just overlaps.The spatial distribution map of acoustic pressure, loudness and the sharpness at the plane place that the distance that adopts this method reconstruct and sound source face is 0.03m.

Fig. 3 (a) is the comparison diagram of the space distribution result of calculation of acoustic pressure while simultaneously existing of the sound source 1 of 800Hz, 79dB and the sound source 2 of 1000Hz, 84dB and loudness.Fig. 3 (b) is the comparison diagram of the space distribution result of calculation of acoustic pressure while simultaneously existing of the sound source 1 of 800Hz, 79dB and the sound source 2 of 1000Hz, 84dB and sharpness.

2. Fig. 4 (a) and Fig. 4 (b) adopt the double sound source sound-field model described in 1 equally, but the parameter of sound source 1 is set to 800Hz, 82dB, be placed on the negative semiaxis of x of rectangular coordinate system in space the (of 0.12m place 0.12m, 0,0); The parameter of target sound source 2 is set to 1000Hz, 84dB, is placed on 0.12m place (0.12m, 0,0) in the x positive axis of rectangular coordinate system in space, and plane microphone array (as shown in Figure 1) is apart from sound source face 0.06m, as shown in Fig. 2 (b).The spatial distribution map of acoustic pressure, loudness and the sharpness at the plane place that the distance that adopts this method reconstruct and sound source face is 0.03m.

Fig. 4 (a) is the comparison diagram of the space distribution result of calculation of acoustic pressure while simultaneously existing of the sound source 1 of 800Hz, 82dB and the sound source 2 of 1000Hz, 84dB and loudness.Fig. 4 (b) is the comparison diagram of the space distribution result of calculation of acoustic pressure while simultaneously existing of the sound source 1 of 800Hz, 82dB and the sound source 2 of 1000Hz, 84dB and sharpness.

Fig. 3 (a) is the spatial distribution map of 800Hz (79dB) and 1000Hz (84dB) two sound sources sound pressure level and loudness while simultaneously existing, and in figure, the sound pressure level of sound source 2 is larger than the sound pressure level of sound source 1, and its loudness value is also larger; In Fig. 4 (a), be the spatial distribution map of 800Hz (82dB) and 1000Hz (84dB) two sound sources sound pressure level and loudness while simultaneously existing, in figure, to remain the sound pressure level of sound source 1 larger for sound pressure level, but that loudness value is the value of sound source 2 is larger.Comparison diagram 3 (a) and Fig. 4 (a), can find out that the overriding noise source location information obtaining may be contrary when adopting different tolerance identification noise source positions.Therefore can not identify the poor noise source position of interior sound field people's auditory perception according to sound physical properties amount information such as sound pressure levels, should adopt according to the Measure Indexes of appraiser's sense of hearing sensation and determine the noise source position that causes that people is angry.

The method that this patent is taked can obtain the space distribution information of the objective parameter of sound quality of the different frequency sound field that exceeds single array measurement aperture extensive area in space.Simultaneously, from traditional to identify the acoustical holography method of sound source according to acoustic pressure different, this method can identify the positional information with the closely-related noise source of the subjective auditory perception of people.When current time is within the rush hour of regulation, and while meeting following two conditions, system is accepted the services request of this lease point, and puts it into set A ⁺in, by the Priority Service of accepting to dispatch buses;

2.3.1 lock ratio cc≤0.1 or α >=0.9;

2.3.2 send the request lease point acceptable maximum walking distance of 500m(resident around) ratio r >=0.5 of total number of leasing in the number that meets α≤0.1 or α >=0.9 condition with interior lease point lock ratio and this region;

2.4 second-level dispatching service window A ^-

In the rush hour of predetermining when the time, and while meeting following two conditions, system is accepted the services request of this lease point, and puts it into set A ^-in, prepare the service that acceptance is dispatched buses;

2.4.1 lock ratio cc≤0.1 or α >=0.9;

2.4.2 send the request lease point acceptable walking ultimate range of 500m(resident around) with the ratio 0.3≤r<0.5 of total number of leasing in the number of interior lease point lock ratio cc≤0.1 or α >=0.9 condition and this region;

Or in the time of in the flat peak time of predetermining when the time, and while meeting following two conditions, system is accepted the services request of this lease point, and puts it into set A ^-in, prepare the service that acceptance is dispatched buses;

2.4.3 lock ratio cc≤0.2 or α >=0.8;

2.4.4 send request lease point around 500m with the satisfy condition ratio r >0.5 of total number of leasing in number and this region of α≤0.2 or α >=0.8 of interior lease point lock ratio;

2.5 non-scheduled service window B

When lease point is discontented, be enough to upper condition constantly, put it in set B, the lease point in this set is not accepted services request.

The lease point of 2.6 second-level dispatching service windows is inserted into scheduling needs to meet such condition in path: the scheduling path that does not as far as possible increase vehicle, the insertion of this lease point can be adjusted the bicycle quantity on dispatching buses, better meet next lease point demand condition, and reduce or do not increase the number of dispatching buses of current use.

Technical conceive of the present invention: dispatch command is divided dispatcher-controlled territory before generating, the unreasonable path of having avoided dispatching buses in driving process; On the basis of scheduling naturally, according to each lease point and region, at the lock ratio of different time sections, lease point dispatch service is divided into different priorities and dispatches, reduced the blindness of dispatching buses and moved, improved dispatching efficiency and masses' satisfaction simultaneously.

Advantage of the present invention: can effectively improve the science of public bicycles management and running, and reduce scheduling path, saving reduction scheduling cost, improve public bicycles utilization factor, alleviate the contradiction of " difficulty of hiring a car, the difficulty of returning the car ".

The dispatcher-controlled territory of Fig. 1 based on auto flowability divided process flow diagram

With reference to accompanying drawing:

The natural mixed scheduling method of public bicycles system of the present invention, concrete steps are as follows:

Step 1, division dispatcher-controlled territory

In conjunction with the dispatching requirement of city public bicycle system, therefore can utilize this auto flowability of public bicycles between lease point, in conjunction with OD(Origin And Destination) service data, city public bicycle system lease point is carried out to region division; And then in conjunction with characteristic attributes such as lease point morning and evening tides direction, lease vertex types in each region, to carrying out secondary division in region, finally realize the region of city public bicycle system dynamic dispatching to divide, be public bicycles system to be carried out to the prerequisite of rational management.Its process flow diagram is as shown in Figure 1:

Step 2, generation dispatch command

2.1 lease point dispatch service grade classification, the feature changing when causing lease point demand for services amount for public bicycles auto flowability, for reducing the operation blindly of dispatching buses, guarantees again the effect of scheduling simultaneously.Public bicycles system lease point is divided three classes:

2.3.1 schedule level one service window A ⁺, preferentially enjoy the lease point set of service;

2.3.2 second-level dispatching service window A ^-, prepare the lease point of the service of accepting and gather

2.3.3 non-scheduled service window B, not yet has the lease point of demand for services and the lease point set of having accepted service.

The definition of 2.2 rush hours and flat peak time, according to the system moving law that Hangzhou public bicycles system service data space-time analysis is drawn, regulation:

Be rush hour:

Flat peak time is: all the other times.

2.3 schedule level one service window A ⁺

When current time is within the rush hour of regulation, and while meeting following two conditions, system is accepted the services request of this lease point, and puts it into set A ⁺in, by the Priority Service of accepting to dispatch buses;

2.3.1 lock ratio cc≤0.1 or α >=0.9;

2.3.2 send the request lease point acceptable maximum walking distance of 500m(resident around) ratio r >=0.5 of total number of leasing in the number that meets α≤0.1 or α >=0.9 condition with interior lease point lock ratio and this region;

2.4 second-level dispatching service window A ^-

In the rush hour of predetermining when the time, and while meeting following two conditions, system is accepted the services request of this lease point, and puts it into set A ^-in, prepare the service that acceptance is dispatched buses;

2.4.1 lock ratio cc≤0.1 or α >=0.9;

2.4.2 send the request lease point acceptable walking ultimate range of 500m(resident around) with the ratio 0.3≤r<0.5 of total number of leasing in the number of interior lease point lock ratio cc≤0.1 or α >=0.9 condition and this region;

Or in the time of in the flat peak time of predetermining when the time, and while meeting following two conditions, system is accepted the services request of this lease point, and puts it into set A ^-in, prepare the service that acceptance is dispatched buses;

2.4.3 lock ratio cc≤0.2 or α >=0.8;

2.4.4 send request lease point around 500m with the satisfy condition ratio r >0.5 of total number of leasing in number and this region of α≤0.2 or α >=0.8 of interior lease point lock ratio;

2.5 non-scheduled service window B

When lease point is discontented, be enough to upper condition constantly, put it in set B, the lease point in this set is not accepted services request.

The lease point of 2.6 second-level dispatching service windows is inserted into scheduling needs to meet such condition in path: the scheduling path that does not as far as possible increase vehicle, the insertion of this lease point can be adjusted the bicycle quantity on dispatching buses, better meet next lease point demand condition, and reduce or do not increase the number of dispatching buses of current use.

Claims (2)

1. the three-dimensional visualization method of the objective parameter of sound quality based on Patch near field acoustic holography method, comprises following step:

1) adopt same small size high density microphone array to carry out repeatedly near-field scan to large and complex structure sound source and measure, obtain the near field acoustical signal information of whole sound source face.In each measurement, record reference point locations signal, as each witness mark signal.

2) according to 1) the near field acoustical signal information that measures, first by carrying out dry calculating mutually with reference microphone signal, obtain the multiple sound pressure signal of the synchronous microphone of all measurement faces, then adopt Patch near field acoustic holography method to obtain the three-dimensional spatial distribution information (acoustic pressure, particle rapidity etc.) of sound field acoustics amount, result of calculation provides with the form of 3D rendering.

The acoustic pressure of Patch near field acoustic holography method definition different measuring face is calculated with following formula:

Complex pressure phase: $\mathrm{\&theta;}\left(\mathrm{\&omega;}\right)=\arg \left[\frac{S_{r,h}\left(\mathrm{\&omega;}\right)}{S_{r,r}\left(\mathrm{\&omega;}\right)}\right]---\left(1\right)$

Multiple sound pressure amplitude: $p\left(\mathrm{\&omega;}\right)=\sqrt{S_{h,h}\left(\mathrm{\&omega;}\right)}---\left(2\right)$

Multiple acoustic pressure size: p (r)=p (ω) e ^{j θ (ω)}(3)

In formula: S representative is relevant calculates, subscript r, h represents microphone signal on reference point and array measurement face.

The sound field transformation for mula of reconstruct face is as follows:

p(r)=p ^T(A ⁺A+θ ²I) ^-1A ⁺α (4)

A in formula ⁺a and A ⁺α is determined by following formula:

${\left[A^{+}A\right]}_{{\mathrm{nn}}^{\&prime;}}=\frac{1}{{\mathrm{\&pi;k}}^2}{\&Integral;\&Integral;}_{-\&infin;}^{\&infin;}{e}^{j(k_z^{*}-k_z)d}{e}^{-j{K}_{\mathrm{xy}}(r_{\mathrm{xy},n}-r_{\mathrm{xy},n^{\&prime;}})}{\mathrm{dk}}_x{\mathrm{dk}}_y---\left(5\right)$

${\left[A^{+}\mathrm{\&alpha;}\right]}_n=\frac{1}{{\mathrm{\&pi;k}}^2}{\&Integral;\&Integral;}_{-\&infin;}^{\&infin;}{e}^{j(k_z^{*}d-k_{z}z)}{e}^{-j{K}_{\mathrm{xy}}\left(r_{\mathrm{xy}}{-r}_{\mathrm{xy},n}\right)}{\mathrm{dk}}_x{\mathrm{dk}}_y---\left(6\right)$

In formula: p is the column vector that the acoustic pressure of all measurement points on measurement face forms, p ^ttransposition for p; R is the Cartesian coordinates of any reconstruction point in space, r=(x, y, z), the acoustic pressure that p (r) is reconstruction point; K is wave number, k _zfor the space wave number in z direction on reconstruction face, * represents complex conjugate; K _xy=(k _x, k _y), k _xfor the space wave number in x direction on reconstruction face, k _yfor the space wave number in y direction on reconstruction face; r _xy=(x, y) is the xy coordinate of reconstruction point, r _{xy, n}=(x _n, y _n), r _{xy, n '}=(x _{n '}, y _{n '}), r _{xy, n}and r _{xy, n '}the xy coordinate that represents respectively microphone measurement point n and n '; D is that measurement face is to the distance of sound source face.

3) according to 2) in sound field information (acoustic pressure, particle rapidity etc.) in the space that obtains, according to the model for coupling of sound field information in space disclosed by the invention and the objective parametric algorithm of sound quality, obtain sound quality information (as loudness, sharpness etc.) the distributed in three dimensions information of position, space, the distributed in three dimensions that has realized the objective parameter of sound quality is visual, and identifies accordingly the position with the closely related sound source of the subjective auditory perception of people.

The computation model of sound quality loudness: according to the loudness definition of Moore, the loudness of the objective parameter of psychologic acoustics is calculated and be take ERB (Equivalent Rectangular Width-equivalent rectangular width) yardstick as basis, in the auditory frequency range of people's ear 0.05kHz～15kHz, set up 372 auditory filters, wherein the corresponding relation of critical band width ERB and frequency f (kHz) can be approximately:

ERB=24.673(0.004368f+1) (7)

In formula: the centre frequency that f is frequency band.

In 0.05kHz～15kHz frequency range, the centre frequency of human auditory system wave filter can be obtained by following formula:

ERB-number=21.366lg(0.004368f+1) (8)

In formula: the centre frequency that f is wave filter.

And the output drive of wave filter can be tried to achieve by following formula:

In 0.05kHz～15kHz frequency range the centre frequency of human auditory system wave filter can by under

$E_i=\frac{\mathrm{\&Sigma;W}\left(g_{\mathrm{ij}}\right)P_j^2}{P_0^2}{E}_0---\left(9\right)$

In formula: E _ibe the output drive of i wave filter, W (g _ij) be the response of i wave filter to the input of frequency j place, for the effective value power of input signal, P ₀for reference sound pressure 2 * 10 ^-5handkerchief.Obtaining on filter output signal basis, can try to achieve characteristic loudness N'.

Final loudness is the characteristic loudness sum that 372 wave filters are tried to achieve, as shown in the formula:

$N=\underset{i=1}{\overset{372}{\mathrm{\&Sigma;}}}{N}_i^{\&prime;}---\left(10\right)$

Sharpness model: in sharpness computation process, sharpness represents with S, and its computing formula is:

$S=0.1043\&times;\frac{{\&Integral;}_0^{24}{N}^{\&prime;}g\left(z\right)\mathrm{dz}}{{\&Integral;}_0^{24}{N}^{\&prime;}\mathrm{dz}}---\left(11\right)$

In formula: N' is the characteristic loudness in Zwicker Scale Model of Loudness, and

$g\left(z\right)=\left\{\begin{array}{cc}1& (z<16)\\ 0.066e^{0.171z}& (z\&GreaterEqual;16)\end{array}\right.---\left(12\right)$

According to 2) in the spatial distribution result of acoustic pressure in the sound field that calculates, and in conjunction with the computation model of the objective parameter of single-point sound quality in space, set up the coupling three-dimensional matrice mapping model of sonic pressure field and loudness field in space, that is:

${{[p(x,y,z,{\mathrm{\&omega;}}_1)\&CenterDot;\&CenterDot;p(x,y,z,{\mathrm{\&omega;}}_m)]}_{1\&times;m}\left[\begin{array}{ccc}{w}_1& \&CenterDot;\&CenterDot;& w_{372}\\ w_1& \&CenterDot;\&CenterDot;& w_{372}\\ \&CenterDot;& \&CenterDot;\&CenterDot;& \&CenterDot;\\ w_1& \&CenterDot;\&CenterDot;& w_{372}\end{array}\right]}_{m\&times;372}={[N_1^{\&prime;}(x,y,z)\&CenterDot;\&CenterDot;N_{372}^{\&prime;}(x,y,z)]}_{1\&times;372}---\left(13\right)$

Or be abbreviated as:

P _iW=N′ (14)

In formula: p _ifor the acoustic pressure under certain arbitrary frequency in location point place in sound field, P _ifor the vector that the acoustic pressure reconstruction value under each frequency of certain position in sound field forms, W is by 372 wave filter w _ithe auditory filter matrix forming, represents the response of people's ear to all frequencies in audio-band, and N ' is characteristic loudness vector.By formula (10), to the every summation in characteristic loudness vector N ', just can obtain the loudness of sound field specified point, and sound field three dimensions node is repeated to this computation process, just can obtain sound field loudness distributed in three dimensions result.The objective parameter distributed in three dimensions of other sound quality result also can adopt with loudness and calculate similar analysis process acquisition.

2. according to the method shown in claim 1, it is characterized in that, described basic harvester is to can be applicable to small-sized plane or the three-dimensional microphone array that large complicated sound source surface measurement is analyzed.

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