CN113347531A - Audio frequency directional system with novel ultrasonic transducer array arrangement mode - Google Patents
Audio frequency directional system with novel ultrasonic transducer array arrangement mode Download PDFInfo
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- CN113347531A CN113347531A CN202110648600.9A CN202110648600A CN113347531A CN 113347531 A CN113347531 A CN 113347531A CN 202110648600 A CN202110648600 A CN 202110648600A CN 113347531 A CN113347531 A CN 113347531A
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- 238000003491 array Methods 0.000 claims abstract description 11
- 238000006243 chemical reaction Methods 0.000 claims description 13
- 238000012545 processing Methods 0.000 claims description 5
- 238000009825 accumulation Methods 0.000 abstract description 3
- 230000017525 heat dissipation Effects 0.000 abstract description 3
- 238000000034 method Methods 0.000 description 8
- 238000013139 quantization Methods 0.000 description 5
- 230000005855 radiation Effects 0.000 description 5
- 238000001914 filtration Methods 0.000 description 4
- 230000005236 sound signal Effects 0.000 description 3
- 238000010586 diagram Methods 0.000 description 2
- 210000005069 ears Anatomy 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000010521 absorption reaction Methods 0.000 description 1
- 230000002238 attenuated effect Effects 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 230000000295 complement effect Effects 0.000 description 1
- 238000009792 diffusion process Methods 0.000 description 1
- 230000008034 disappearance Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000020169 heat generation Effects 0.000 description 1
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- 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
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
- H04R3/00—Circuits for transducers, loudspeakers or microphones
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
- H04R2201/00—Details of transducers, loudspeakers or microphones covered by H04R1/00 but not provided for in any of its subgroups
- H04R2201/40—Details of arrangements for obtaining desired directional characteristic by combining a number of identical transducers covered by H04R1/40 but not provided for in any of its subgroups
- H04R2201/401—2D or 3D arrays of transducers
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- Health & Medical Sciences (AREA)
- Otolaryngology (AREA)
- Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Acoustics & Sound (AREA)
- Signal Processing (AREA)
- Circuit For Audible Band Transducer (AREA)
Abstract
The invention relates to the technical field of audio frequency directional systems, in particular to an audio frequency directional system with a novel ultrasonic transducer array arrangement mode. The invention relates to an audio frequency directional system with a novel ultrasonic transducer array arrangement mode, which arranges a full digital loudspeaker array module into a honeycomb shape through a plurality of transducer arrays, arranges the transducer array with long sound wave propagation distance at the middle position, and arranges the transducer array with short sound wave propagation distance at the edge for low-order arrangement, thereby improving the signal-to-noise ratio, converting a digital signal into an analog signal, completely working the whole system in an on-off binary state, avoiding the restriction of heat accumulation and solving the heat dissipation problem of an acoustic parametric array.
Description
Technical Field
The invention relates to the technical field of audio frequency orientation systems, in particular to an audio frequency orientation system with a novel ultrasonic transducer array arrangement mode.
Background
At present, in daily life, sound waves exist in all corners of the surrounding space, useful sound waves and noise are mixed with each other, and the working quality and the working efficiency of people are seriously influenced. Therefore, in some occasions with high requirements on the environment, the sound waves are required to have strong directivity, so that noise pollution is avoided, and a relatively independent and quiet working space is provided for people. In addition, the directional sound wave can reduce energy loss caused by sound wave diffusion, and information can be transmitted most directly.
There are three main methods for implementing audio frequency orientation: dome speakers, acoustic parametric arrays, speaker arrays. The efficiency of converting the original frequency power into parametric sound by the traditional acoustic parametric array is very low, so that a lot of work is required to improve the efficiency of the traditional acoustic parametric array, but the effect is not large, which has important influence on the practical application of the traditional acoustic parametric array. In recent years, the problems of power consumption and heat generation are successfully solved by a full digital loudspeaker array system driven by a digital wave, the electroacoustic conversion efficiency of the whole system is greatly improved, the miniaturization level can be realized, and the full digital audio frequency directional system is widely used.
The acoustic parametric array is characterized in that a special transmitting transducer is used for transmitting two original frequency waves into a medium, radiation sources with new frequency components (sum frequency waves and difference frequency waves) are generated through interaction due to nonlinearity of the medium, the radiation sources radiate sound waves to the space, the amplitude of the original waves is continuously reduced and finally disappears in the transmission process due to absorption of the medium, the new radiation sources are continuously generated in the disappearance process of the original waves, but the intensity of the sources is exponentially attenuated along with the distance, and the mode realizes that the conversion efficiency of the acoustic frequency directional energy is low, the nonlinearity of air is poor, and the tone quality of a reconstructed sound field is influenced.
In view of the above-mentioned drawbacks, the present designer is actively making research and innovation to create an audio frequency directional system with a novel ultrasonic transducer array arrangement, so that the audio frequency directional system has more industrial utility value.
Disclosure of Invention
In order to solve the above technical problems, an object of the present invention is to provide an audio frequency directional system with a novel ultrasonic transducer array arrangement, in which a full digital speaker array module is arranged to form a honeycomb shape through a plurality of transducer arrays, the transducer array with a long acoustic wave propagation distance is arranged at a middle position, and the transducer array with a short acoustic wave propagation distance is arranged at an edge to perform low-order arrangement, thereby improving the signal-to-noise ratio.
The invention relates to an audio frequency directional system with a novel ultrasonic transducer array arrangement mode, which comprises an analog signal module, a rear-stage buffer circuit module and a full-digital loudspeaker array module, wherein the analog-digital conversion module is connected to the analog signal module, the signal processing module is connected with the analog-digital conversion module, the rear-stage buffer circuit module is connected with the signal processing module, the full-digital loudspeaker array module is connected with the rear-stage buffer circuit module, and the full-digital loudspeaker array module is formed into a honeycomb shape by arranging a plurality of transducer arrays. The analog signal module is used for generating the original audio signal. The analog-to-digital conversion module is used for converting the original audio signal into a digital signal. The full digital loudspeaker array module completes electroacoustic conversion and realizes acoustic radiation. The post-stage buffer circuit module is used for amplifying the digital coded signal to drive the step S5, namely, the all-digital transducer array.
Furthermore, at least seven transducers are arranged in the transducer in the all-digital loudspeaker array module from large sound wave propagation distance to small sound wave propagation distance.
Furthermore, the transducer array is arranged to form a honeycomb shape, and the transducer array is respectively provided with a first transducer, a second transducer, a third transducer, a fourth transducer, a fifth transducer, a sixth transducer and a seventh transducer from the outside to the inside.
Further, a first transducer, a second transducer, a third transducer, a fourth transducer, a fifth transducer, a sixth transducer and a seventh transducer are sequentially arranged, and the propagation distances of the acoustic waves are sequenced as follows: the first energy converter, the second energy converter, the third energy converter, the fourth energy converter, the fifth energy converter, the sixth energy converter and the seventh energy converter are connected in series.
Further, the signal processor module eliminates the signal above 20 kHz.
By the scheme, the invention at least has the following advantages:
the invention relates to an audio frequency directional system with a novel ultrasonic transducer array arrangement mode, which arranges a full digital loudspeaker array module into a honeycomb shape through a plurality of transducer arrays, arranges the transducer array with long sound wave propagation distance at the middle position, and arranges the transducer array with short sound wave propagation distance at the edge for low-order arrangement, thereby improving the signal-to-noise ratio, better utilizing the low-pass filtering characteristic of human ears, converting a digital signal into an analog signal, completely working the whole system in an on-off binary state, avoiding the restriction of heat accumulation, solving the heat dissipation problem of an acoustic parametric array and facilitating high-power operation.
The foregoing description is only an overview of the technical solutions of the present invention, and in order to make the technical solutions of the present invention more clearly understood and to implement them in accordance with the contents of the description, the following detailed description is given with reference to the preferred embodiments of the present invention and the accompanying drawings.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate a certain embodiment of the present invention, and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained according to the drawings without inventive efforts.
FIG. 1 is a schematic structural view of the present invention;
FIG. 2 is a schematic diagram of the analog-to-digital conversion module of FIG. 1;
fig. 3 is a schematic structural diagram of the all-digital speaker array module in fig. 1.
In the figure, 1 is a first transducer, 2 is a second transducer, 3 is a third transducer, 4 is a fourth transducer, 5 is a fifth transducer, 6 is a sixth transducer, and 7 is a seventh transducer.
Detailed Description
The following detailed description of embodiments of the present invention is provided in connection with the accompanying drawings and examples. The following examples are intended to illustrate the invention but are not intended to limit the scope of the invention.
Referring to fig. 1 and 2, an audio directional system with a novel ultrasonic transducer array arrangement according to a preferred embodiment of the present invention includes an analog signal module, a rear-stage buffer circuit module, and a full digital speaker array module, where the analog-to-digital conversion module is connected to the analog signal module, the signal processing module is connected to the analog-to-digital conversion module, the rear-stage buffer circuit module is connected to the signal processing module, the full digital speaker array module is connected to the rear-stage buffer circuit module, and the full digital speaker array module is formed by arranging a plurality of transducer arrays to form a honeycomb shape.
As shown in fig. 1 to fig. 3, at least seven kinds of transducers are arranged in the all-digital speaker array module from large to small in the sound wave propagation distance.
Referring to fig. 1 to 3, the array of transducers is arranged to form a honeycomb shape, and the first transducer, the second transducer, the third transducer, the fourth transducer, the fifth transducer, the sixth transducer and the seventh transducer are respectively arranged from the outside to the inside.
Referring to fig. 1 to 3, a first transducer 1, a second transducer 2, a third transducer 3, a fourth transducer 4, a fifth transducer 5, a sixth transducer 6, and a seventh transducer 7 are sequentially arranged, and the propagation distances of the acoustic waves are ordered as follows: transducer one 1, transducer two 2, transducer three 3, transducer four 4, transducer five 5, transducer six 6 and transducer seven 7.
As shown in fig. 1 to 3, the signal processor module eliminates the signal above 20 kHz. The signal processor module is used for filtering and controlling the digital signals and filtering signals above 20 kHz.
As shown in fig. 1 to fig. 3, the analog-to-digital conversion module is used to convert the original audio signal into a digital signal, and adopts a uniform PCM encoding mode, which mainly includes sampling, holding, quantizing, encoding, and the like. The quantization method mainly comprises a round-tailed rounding method and a rounding method, wherein the round-tailed rounding quantization method has the maximum quantization error of 1LSB, and the rounding quantization method has the maximum quantization error of LSB/2; the coding takes the form of two's complement.
The full digital loudspeaker array completes the electroacoustic conversion and realizes the sound radiation. Firstly, numbering all transducer units according to the sequence of 1 to 2N-1 by adopting a bit and switch control mode;then, the decimal value corresponding to the PCM data frame is calculated, and assuming that the numerical value at the nth bit is bn, the decimal value obtained by weighted summation is
And finally, turning on all transducer units with serial numbers from 1 to Am according to the calculated bit sum Am. The signal input to the full digital loudspeaker array is
The reconstructed sound field model is
The working principle of the invention is as follows: the full digital loudspeaker array module is arranged to form a honeycomb shape through a plurality of transducer arrays, the transducer arrays with long sound wave propagation distance are arranged at the middle position, and the transducer arrays with short sound wave propagation distance are arranged at the edge to be arranged at a low position, so that the signal-to-noise ratio is improved, the low-pass filtering characteristic of human ears is better utilized, digital signals are converted into analog signals, the whole system completely works in an on-off binary state, the restriction of heat accumulation is avoided, the heat dissipation problem of an acoustic parametric array is solved, and high-power operation is facilitated.
The points to be finally explained are: first, in the description of the present application, it should be noted that, unless otherwise specified and limited, the terms "mounted," "connected," and "connected" should be understood broadly, and may be a mechanical connection or an electrical connection, or a communication between two elements, and may be a direct connection, and "upper," "lower," "left," and "right" are only used to indicate a relative positional relationship, and when the absolute position of the object to be described is changed, the relative positional relationship may be changed;
secondly, the method comprises the following steps: in the drawings of the disclosed embodiments of the invention, only the structures related to the disclosed embodiments are referred to, other structures can refer to common designs, and the same embodiment and different embodiments of the invention can be combined with each other without conflict;
and finally: the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, it should be noted that, for those skilled in the art, many modifications and variations can be made without departing from the technical principle of the present invention, and these modifications and variations should also be regarded as the protection scope of the present invention.
Claims (5)
1. The utility model provides an audio frequency directional system with novel ultrasonic transducer array mode of arranging, includes analog signal module, back level buffer circuit module and full digital loudspeaker array module, and the analog-to-digital conversion module is connected on analog signal module, and the analog-to-digital conversion module is connected to the signal processing module, and back level buffer circuit module, its characterized in that are connected to full digital loudspeaker array module are connected to back level buffer circuit module: the full digital loudspeaker array module is formed by arranging a plurality of transducer arrays into a honeycomb shape.
2. An acoustic frequency direction system with a novel ultrasonic transducer array arrangement as claimed in claim 1, wherein: at least seven transducers are arranged in the transducer in the all-digital loudspeaker array module from large to small in sound wave propagation distance.
3. An acoustic frequency direction system with a novel ultrasonic transducer array arrangement as claimed in claim 1, wherein: the transducer array is arranged to form a honeycomb shape, and a first transducer, a second transducer, a third transducer, a fourth transducer, a fifth transducer, a sixth transducer and a seventh transducer are respectively arranged from the outer side to the inner side.
4. An acoustic frequency direction system with a novel ultrasonic transducer array arrangement as claimed in claim 3, wherein: the transducer I (1), the transducer II (2), the transducer III (3), the transducer IV (4), the transducer V (5), the transducer six (6) and the transducer seven (7) are sequentially arranged, and the propagation distances of the sound waves are sequenced as follows: transducer one (1) > transducer two (2) > transducer three (3) > transducer four (4) > transducer five (5) > transducer six (6) > transducer seven (7).
5. An acoustic frequency direction system with a novel ultrasonic transducer array arrangement as claimed in claim 1, wherein: the signal processor module eliminates signals above 20 kHz.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202110648600.9A CN113347531A (en) | 2021-06-10 | 2021-06-10 | Audio frequency directional system with novel ultrasonic transducer array arrangement mode |
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| CN202110648600.9A CN113347531A (en) | 2021-06-10 | 2021-06-10 | Audio frequency directional system with novel ultrasonic transducer array arrangement mode |
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| CN113347531A true CN113347531A (en) | 2021-09-03 |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115825968A (en) * | 2023-01-09 | 2023-03-21 | 北京海卓同创科技有限公司 | Side-scan image generation method and system and side-scan sonar device |
| CN116684784A (en) * | 2023-06-29 | 2023-09-01 | 中国科学院声学研究所 | Acoustic playback method and system based on parametric array loudspeaker array |
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Cited By (3)
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| CN115825968A (en) * | 2023-01-09 | 2023-03-21 | 北京海卓同创科技有限公司 | Side-scan image generation method and system and side-scan sonar device |
| CN116684784A (en) * | 2023-06-29 | 2023-09-01 | 中国科学院声学研究所 | Acoustic playback method and system based on parametric array loudspeaker array |
| CN116684784B (en) * | 2023-06-29 | 2024-03-12 | 中国科学院声学研究所 | Acoustic playback method and system based on parametric array loudspeaker array |
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