CN112040370A - Loudspeaker array module, directional broadcasting device and directional broadcasting control method - Google Patents
Loudspeaker array module, directional broadcasting device and directional broadcasting control method Download PDFInfo
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- 238000003199 nucleic acid amplification method Methods 0.000 claims description 18
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- H—ELECTRICITY
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- H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
- H04R1/00—Details of transducers, loudspeakers or microphones
- H04R1/20—Arrangements for obtaining desired frequency or directional characteristics
- H04R1/32—Arrangements for obtaining desired frequency or directional characteristics for obtaining desired directional characteristic only
- H04R1/40—Arrangements for obtaining desired frequency or directional characteristics for obtaining desired directional characteristic only by combining a number of identical transducers
- H04R1/403—Arrangements for obtaining desired frequency or directional characteristics for obtaining desired directional characteristic only by combining a number of identical transducers loud-speakers
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Abstract
The invention discloses a loudspeaker array module, a directional broadcasting device and a directional broadcasting control method, wherein the loudspeaker array module comprises N groups of loudspeaker sub-arrays, each group of loudspeaker sub-arrays comprises K loudspeakers, K is 4N +1, and N is 1,2, …; k loudspeakers of the (j) th loudspeaker subarray group 1 are linearly arranged at equal intervals D; the remaining j-th 2,3, …, N groups of speaker sub-arrays: n loudspeakers in the jth group of loudspeaker sub-arrays are equally spaced by 2j‑1D is linearly arranged at the left side of the j-1 th group of loudspeakers, and the other n loudspeakers in the j-th group of loudspeaker sub-arrays are equally spaced by 2j‑1And D is linearly arranged on the right side of the j-1 group of loudspeakers, 2n loudspeakers arranged on the left side and the right side of the j-1 group of loudspeakers and the odd-numbered 2n +1 loudspeakers in the j-1 group of loudspeaker sub-arrays form the j group of loudspeaker sub-arrays together. The method and the device can solve the problem of inconsistent sound at different positions of the sound field in the directional broadcasting in the prior art, improve the broadcasting tone quality and improve the experience of customers.
Description
Technical Field
The invention belongs to the technical field of public broadcasting, is subdivided into a directional broadcasting technology, and particularly relates to a loudspeaker array module, a directional broadcasting device and a directional broadcasting control method.
Background
The directional broadcasting is a method in which a plurality of speakers are arranged in a line speaker array, and a strong sound pressure is generated in a predetermined direction (main lobe direction) and a weak sound pressure is generated in the other direction (side lobe direction). The wave front of the loudspeaker array, through coupling over the entire audio frequency range, is caused to propagate in a beam in a certain direction. The phase and amplitude of input signals of each array element in the array are controlled, so that sound waves are superposed in a specified place or direction and destructively interfered at other positions, and directional broadcasting is realized.
The technical principle of directional broadcasting is essentially the control of the sound field, and the prior art method includes two methods of delay processing and phase adjustment of signals of each loudspeaker, so that sound is concentrated to a certain direction to propagate. The sound field obtained by the first time delay processing method has good sound quality, but the sound pressure contrast between the main lobe direction and the side lobe direction is low, namely, the directional effect is weak; the second phase adjustment method is a frequency domain processing method, and because the frequency points of the signal are equally and equally spaced, the attenuation coefficients of the frequency points are different, and finally, the sound is distorted.
Disclosure of Invention
The invention provides a loudspeaker array module, a directional broadcasting device and a directional broadcasting control method, which can solve the problem of inconsistent sound at different positions of a sound field in directional broadcasting in the prior art, improve the broadcasting tone quality and improve the experience of customers.
In order to achieve the technical purpose, the invention adopts the following technical scheme:
a loudspeaker array module comprising N groups of loudspeaker sub-arrays, each group comprising K loudspeakers, K being 4N +1, N being 1,2, …;
the K loudspeakers of the (j) th 1 th group of loudspeaker sub-arrays are linearly arranged at equal intervals D, and the K loudspeakers in the group of loudspeaker sub-arrays are numbered as j _1, j _2, … and j _ K in sequence;
the remaining j- th 2,3, …, N groups of speaker sub-arrays: n loudspeakers in the jth group of loudspeaker sub-arrays are equally spaced by 2j-1D is linearly arranged at the left side of the j-1 th group of loudspeakers, and the other n loudspeakers in the j-th group of loudspeaker sub-arrays are equally spaced by 2j-1D are linearly arranged in the j-1 th groupThe right side of the loudspeaker, 2n loudspeakers arranged at the left and right sides of the j-1 th group of loudspeakers and 2n +1 loudspeakers which are numbered in odd numbers in the j-1 th group of loudspeaker sub-arrays form a space of 2j-1D, the K speakers in the jth group of speaker sub-arrays are numbered sequentially as j _1, j _2, …, j _ K.
The invention also provides a directional broadcasting device, which comprises the directional broadcasting device and a plurality of filters, wherein the filters are arranged between the loudspeaker and the sound signal input end; a filter for K loudspeaker input ends of the jth group of loudspeaker sub-arrays, the filter interval of which comprises a frequency interval UN-j+1；
Wherein the frequency interval UiI 1,2, …, N, determined by the frequency range U of the sound signal0Dividing the frequency domain into N intervals and sequencing the intervals from small to large, wherein the central frequencies of every two adjacent frequency intervals meet fi+1/fi≈2。
In a preferred embodiment of the directional broadcasting apparatus, if the filter interval of the filter at the input of the speaker includes a frequency interval UNThe filter is set to a high pass filter.
In a more preferred directional broadcaster solution, the frequency range of the sound signal is [200,4000 ].
In a more preferred directional broadcaster solution, the same filter is shared by 2 symmetric loudspeakers in each loudspeaker sub-array.
In a more preferred technical scheme of the directional broadcasting device, a power amplification module is arranged between the filter and the loudspeaker.
The invention also provides a directional broadcast control method with constant beam width, which is applied to any directional broadcast device, and comprises the following steps:
the sound signal input end acquires a sound signal and respectively sends the sound signal to each filter;
each filter filters the received sound signal according to the respective filtering interval, and then sends the sound signal of the filtering interval to the corresponding connected loudspeaker for broadcasting.
In a more preferred technical scheme of the directional broadcast control method, a power amplification module is arranged between a filter and a loudspeaker, after the filter obtains a sound signal in a filtering interval, the sound signal in the filtering interval is firstly sent to the power amplification module for power amplification, and then the power amplification module sends the sound signal after power amplification to the loudspeaker for broadcasting.
Advantageous effects
According to the loudspeaker array module, the directional broadcasting device and the directional broadcasting control method, through setting a plurality of groups of loudspeaker sub-arrays, including the distance between each group of loudspeaker sub-arrays and the distribution of the sound signals in the corresponding frequency band, the beam patterns of the sound signals in different frequency bands are basically kept consistent, so that the consistency of the sound in a sound field is ensured, the broadcasting tone quality is improved, and the user experience is improved.
Drawings
FIG. 1 is a schematic diagram of a speaker array;
FIG. 2 illustrates the beam shapes at different frequencies according to the prior art;
FIG. 3 is a diagram of speaker array profiles corresponding to center frequencies f0 and f1, in accordance with an embodiment of the present invention;
FIG. 4 is a diagram of a speaker array module distribution according to an embodiment of the present invention;
FIG. 5 is a design diagram of a directional broadcasting apparatus according to an embodiment of the present invention;
fig. 6 shows the corresponding beam shapes at different center frequencies according to the embodiment of the present invention.
Detailed Description
The following describes embodiments of the present invention in detail, which are developed based on the technical solutions of the present invention, and give detailed implementation manners and specific operation procedures to further explain the technical solutions of the present invention.
The invention provides a loudspeaker array module, comprising N groups of loudspeaker sub-arrays, wherein each group of loudspeaker sub-array comprises K loudspeakers, K is 4N +1, N is 1,2, …;
the K loudspeakers of the (j) th-1 group of loudspeaker sub-arrays are linearly arranged according to the equal spacing d, and the K loudspeakers in the group of loudspeaker sub-arrays are numbered as j _1, j _2, … and j _ K in sequence;
the remaining j- th 2,3, …, N groups of speaker sub-arrays: n loudspeakers in the jth group of loudspeaker sub-arrays are equally spaced by 2j-1D is linearly arranged at the left side of the j-1 th group of loudspeakers, and the other n loudspeakers in the j-th group of loudspeaker sub-arrays are equally spaced by 2j-1D are linearly arranged on the right side of the j-1 group of loudspeakers, 2n loudspeakers arranged on the left side and the right side of the j-1 group of loudspeakers and 2n +1 loudspeakers numbered in the j-1 group of loudspeaker sub-arrays form a space of 2j-1D, the K loudspeakers in the jth group of loudspeaker sub-arrays are numbered sequentially as j _1, j _2, …, j _ K.
The invention also provides a directional broadcasting device, which comprises the directional broadcasting device and a plurality of filters, wherein the filters are arranged between the loudspeaker and the sound signal input end; a filter for K loudspeaker input ends of the jth group of loudspeaker sub-arrays, the filter interval of which comprises a frequency interval UN-j+1；
Wherein the frequency interval UiI 1,2, …, N, determined by the frequency range U of the sound signal0Dividing the frequency domain into N intervals and sequencing the intervals from small to large, wherein the central frequencies of every two adjacent frequency intervals meet fi+1/fi≈2。
For each set of sub-arrays of loudspeakers, since the loudspeakers are linearly arranged at equal intervals, as shown in fig. 1, the directivity function of the loudspeaker array can be expressed as:
wherein,
the included angle between the center of the loudspeaker array and the sound transmission direction is referred to, d is the distance between the loudspeakers in the loudspeaker array, and lambda represents the wavelength of the sound signal;
from the directivity function, the beam shape of the loudspeaker array is related to the pitch d of the loudspeakers, the signal wavelength λ, and the number n of loudspeakers in the array. Fig. 2 shows a schematic diagram of the change of the beam shape of the loudspeaker array when n is 10 and d is 0.05m, and the frequency of the input sound signal is changed from 400Hz to 4000 Hz. Wherein, the frequency corresponding to the widest wave beam is 400Hz, and the frequency corresponding to the narrowest wave beam is 4000 Hz. As can be seen from fig. 2, the larger the frequency (the smaller the wavelength λ), the narrower the beam when the number of speakers n is fixed.
This frequency dependent beam shape results in inconsistent attenuation of frequencies at different locations in the sound field, resulting in distortion of the sound. Aiming at the problem, the loudspeaker array module provided by the invention obtains relatively consistent beam curves at different frequency bands by reasonably arranging the loudspeakers, so that the consistency of the sound field is ensured.
The loudspeaker array module comprises N loudspeaker sub-arrays, wherein the quantity of the loudspeakers of each loudspeaker sub-array is the same; and j equals 1,2,3, …, the spacing of N groups of speaker sub-arrays is D,2D, …,2j-1*D,…,2N-1D, the filtering intervals of the corresponding filters respectively comprise UN,UN-1,…,UN-j+1,…,U1Then the center frequency of the frequency interval is fN,fN-1,…,fN-j+1,…,f1. Due to fi+1/fiApproximately equals 2, therefore, the products of the center frequency of the corresponding frequency interval of different loudspeaker sub-arrays and the loudspeaker spacing are kept consistent, namely the invention satisfies the sum of n in the directional function of each loudspeaker sub-array
And the directivity function values are consistent, so that the beam curves of the sound signals in each frequency zone section are consistent basically, namely the beam widths are consistent, and the consistency of the sound field of the loudspeaker array module can be ensured.
In a more preferred embodiment, the filter interval of the filter at the input of the loudspeaker comprises a frequency interval UNThe filter is set to a high pass filter.
In a more preferred embodiment, the sound signal has a frequency range of [200,4000 ].
In a more preferable scheme, the symmetrical 2 loudspeakers in each loudspeaker sub-array share the same filter, and a power amplification module is arranged between the rear ends of each filter.
The invention also provides an embodiment of a directional broadcast control method with constant beam width, which is applied to the directional broadcast device and comprises the following steps:
the sound signal input end acquires a sound signal and respectively sends the sound signal to each filter;
each filter filters the received sound signal according to the respective filtering interval, then sends the sound signal in the filtering interval to the power amplification module for power amplification, and then the power amplification module sends the sound signal after power amplification to the loudspeaker for broadcasting.
A case is given below to explain the implementation principle. Let N be 1, K be 5, N be 3, and d be 0.05 m. It can be seen that the resulting speaker array module includes 9 speakers in total, as shown in fig. 4. The loudspeakers 3, 4, 5, 6 and 7 are uniformly arranged according to the distance d to form a 1 st group of loudspeaker sub-arrays with the distance d; the loudspeaker 2 and the loudspeaker 8 are respectively arranged on the left side of the loudspeaker 3 and the right side of the loudspeaker 7 according to the distance 2d, so that 5 loudspeakers 2,3, 5, 7 and 8 form a 2 nd group of loudspeaker sub-arrays with the distance 2 d; the loudspeaker 1 and the loudspeaker 9 are respectively arranged on the left side of the loudspeaker 3 and the right side of the loudspeaker 8 according to a distance 4d, and 5 loudspeakers 1,2, 5, 8 and 9 form a 3 rd group loudspeaker sub-array with the distance 4 d.
The 3 groups of speaker sub-arrays obtained above have the respective pitches d,2d and 3d and the respective processing frequency intervals are U3＝[2000,4000],U2＝[1000,2000],U1＝[200,1000]The center frequencies of the sound signals corresponding to the respective frequency sections are 3000Hz, 1500Hz, and 600 Hz. In the actual processing of the present embodiment, since the sampling frequency of the sound signal is 8kHz, the frequency interval U is divided in consideration of the aliasing problem3Is set to 3900 instead of exactly half the sampling frequency.
Loudspeaker 1 and loudspeaker 9 belong only to subarray 3, so that the filter of the filter at its input has a filter interval U1＝[200,1000]；
Loudspeaker 2 and loudspeaker 8 belong to both sub-array 3 and sub-array 2, so that the filter space of the filter at its input includes both U and U1And U2I.e. the filter interval is U1∪U2＝[200,2000]；
The loudspeaker 5 belongs to the subarrays 1,2,3 simultaneously, so that the filter space of the filter at its input comprises U at the same time1、U2、U3I.e. its filtering interval is U1∪U2∪U3＝[200,4000]。
From the filter intervals of the input ends of the speakers, 5 filters can be set in the present embodiment, and based on the frequency range of the input sound signal in the present embodiment being [200,4000], the 5 filters can be set as: a first band pass filter FIR1 with a passband of [200Hz,1000Hz ]; a second band pass filter FIR2 with a passband of [200Hz,2000Hz ]; a third high pass filter FIR3, transition frequency 1000 Hz; a fourth high pass filter FIR4, transition frequency 2000 Hz; the fifth high pass filter FIR5, having a transition frequency of 200 Hz.
The 2 symmetric speakers in each speaker sub-array share the same filter, and a power amplification module is arranged between the rear ends of each filter, so that the scheme of the directional broadcasting apparatus of the present embodiment is shown in fig. 5, and the corresponding beam shapes obtained under different center frequencies are shown in fig. 6. As can be seen from fig. 6, according to the scheme of the present invention, the corresponding beam shapes and beam widths at different center frequencies are substantially consistent, and compared with the existing uniformly arranged speaker array, the sound consistency at different positions of the sound field of the speaker array module is better, and the distortion is lower.
The above embodiments are preferred embodiments of the present application, and those skilled in the art can make various changes or modifications without departing from the general concept of the present application, and such changes or modifications should fall within the scope of the claims of the present application.
Claims (8)
1. A loudspeaker array module comprising N groups of loudspeaker sub-arrays, each group comprising K loudspeakers, K being 4N +1 and N being 1,2, …;
the K loudspeakers of the (j) th 1 th group of loudspeaker sub-arrays are linearly arranged at equal intervals D, and the K loudspeakers in the group of loudspeaker sub-arrays are numbered as j _1, j _2, … and j _ K in sequence;
the remaining j-th 2,3, …, N groups of speaker sub-arrays: n loudspeakers in the jth group of loudspeaker sub-arrays are equally spaced by 2j -1D is linearly arranged at the left side of the j-1 th group of loudspeakers, and the other n loudspeakers in the j-th group of loudspeaker sub-arrays are equally spaced by 2j-1D are linearly arranged on the right side of the j-1 group of loudspeakers, 2n loudspeakers arranged on the left side and the right side of the j-1 group of loudspeakers and 2n +1 loudspeakers numbered in the j-1 group of loudspeaker sub-arrays form a space of 2j-1D, the K speakers in the jth group of speaker sub-arrays are numbered sequentially as j _1, j _2, …, j _ K.
2. A directional broadcasting apparatus comprising the directional broadcasting apparatus of claim 1 and a plurality of filters, the filters being disposed between the speaker and the sound signal input terminal; a filter for K loudspeaker input ends of the jth group of loudspeaker sub-arrays, the filter interval of which comprises a frequency interval UN-j+1；
Wherein the frequency interval UiI 1,2, …, N, determined by the frequency range U of the sound signal0Dividing into N intervals and sequencing from small to big, every two adjacent intervalsThe center frequency of the frequency interval satisfies fi+1/fi≈2。
3. A directional broadcasting device according to claim 2, characterized in that the filter interval of the filter at the input of the loudspeaker includes the frequency interval UNThe filter is set to a high pass filter.
4. A directional broadcasting device according to claim 2, characterized in that the frequency range of the sound signal is [200,4000 ].
5. The directional broadcasting device of claim 2, wherein the same filter is shared by the symmetrical 2 speakers in each speaker sub-array.
6. The method of claim 2, wherein a power amplification module is disposed between the filter and the speaker.
7. A directional broadcast control method with constant beamwidth, which is applied to the directional broadcasting device of any one of claims 2-5, the method comprising:
the sound signal input end acquires a sound signal and respectively sends the sound signal to each filter;
each filter filters the received sound signal according to the respective filtering interval, and then sends the sound signal of the filtering interval to the corresponding connected loudspeaker for broadcasting.
8. The method as claimed in claim 7, wherein a power amplification module is disposed between the filter and the speaker, and after the filter obtains the sound signal of the filtering interval section through filtering, the sound signal of the filtering interval section is firstly sent to the power amplification module for power amplification, and then the power amplification module sends the sound signal after power amplification to the speaker for broadcasting.
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN112835032A (en) * | 2020-12-31 | 2021-05-25 | 中国海洋大学 | But linear array that unmanned aerial vehicle carried on interferes pronunciation warning sodar in epidemic prevention |
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| JP2005236737A (en) * | 2004-02-20 | 2005-09-02 | Toa Corp | Broadcast system |
| CN1929697A (en) * | 2006-09-29 | 2007-03-14 | 南京大学 | Optimization method and device for loudspeaker array |
| US20130259238A1 (en) * | 2012-04-02 | 2013-10-03 | Qualcomm Incorporated | Systems, methods, apparatus, and computer-readable media for gestural manipulation of a sound field |
| US20190014430A1 (en) * | 2017-07-07 | 2019-01-10 | Harman Becker Automotive Systems Gmbh | Loudspeaker-room system |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2005236737A (en) * | 2004-02-20 | 2005-09-02 | Toa Corp | Broadcast system |
| CN1929697A (en) * | 2006-09-29 | 2007-03-14 | 南京大学 | Optimization method and device for loudspeaker array |
| US20130259238A1 (en) * | 2012-04-02 | 2013-10-03 | Qualcomm Incorporated | Systems, methods, apparatus, and computer-readable media for gestural manipulation of a sound field |
| US20190014430A1 (en) * | 2017-07-07 | 2019-01-10 | Harman Becker Automotive Systems Gmbh | Loudspeaker-room system |
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