CN113068102B - Excitation generator - Google Patents
Excitation generator Download PDFInfo
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- CN113068102B CN113068102B CN202110311560.9A CN202110311560A CN113068102B CN 113068102 B CN113068102 B CN 113068102B CN 202110311560 A CN202110311560 A CN 202110311560A CN 113068102 B CN113068102 B CN 113068102B
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- sound
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- wave
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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
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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
- H04R19/00—Electrostatic transducers
- H04R19/02—Loudspeakers
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02D—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN INFORMATION AND COMMUNICATION TECHNOLOGIES [ICT], I.E. INFORMATION AND COMMUNICATION TECHNOLOGIES AIMING AT THE REDUCTION OF THEIR OWN ENERGY USE
- Y02D30/00—Reducing energy consumption in communication networks
- Y02D30/70—Reducing energy consumption in communication networks in wireless communication networks
Abstract
The invention discloses an excitation generator, comprising: an audio signal generator for generating a desired primary sound field audio signal, the audio signal generator being an inner and outer sound field generator having a multi-layered sound field structure; the controller is used for adjusting the frequency and the power of the audio signal of the main sound field and the amplification factor of the audio signal; and the display device is used for displaying the frequency of the current audio signal, the phase difference or the frequency difference of the outer sound field and the signal output power information. By adopting the technical scheme of the invention, the problem of directional transmission of sound waves is solved, so that the sound waves are not dispersed when transmitted in a medium; the problem of secret transmission of a core sound carrier signal in a sound signal is solved; the problem of the directional emission of sound signal is solved in the detection field, can carry out sound detection more accurately.
Description
Technical Field
The invention belongs to the technical field of sound treatment, and particularly relates to an excitation generator.
Background
It is well known that laser light sources have many more excellent characteristics than conventional light sources, such as good directivity, less divergence, high brightness, high coherence, single frequency, and so on. Both sound and light have volatility, but they are essentially different, light is electromagnetic wave, is transverse wave; the acoustic wave is a mechanical wave and a longitudinal wave. In a typical medium, the speed of light is much faster than the speed of sound, and the light energy propagates in vacuum and sound is not viable.
Because acoustic waves are essentially different from light waves, the principles of their generation and propagation are quite different. The laser has made many fields such as optical communication, optical measurement, optical research, etc. develop rapidly, and in the acoustic field, the traditional research method is still followed. The modification of the sound wave along the thought of manufacturing the laser enables the sound wave to have good directivity like the laser and be not suitable for divergence, and no report is seen yet.
Disclosure of Invention
The invention aims to solve the technical problem of providing an excitation generator to solve the problem of directional transmission of sound waves, so that the sound waves are not dispersed when transmitted in a medium; the problem of secret transmission of a core sound carrier signal in a sound signal is solved; the problem of the directional emission of sound signal is solved in the detection field, can carry out sound detection more accurately.
In order to achieve the above purpose, the invention adopts the following technical proposal
An excitation generator comprising:
the audio signal generator is used for generating a required main sound field audio signal, and the audio signal generator is an inner sound field generator and an outer sound field generator with a multilayer annular sound field structure;
the controller is used for adjusting the frequency and the power of the audio signal of the main sound field and the amplification factor of the audio signal;
and the display device is used for displaying the frequency of the current audio signal, the phase difference or the frequency difference of the outer sound field and the signal output power information.
Preferably, each layer in the multilayer annular sound field structure adopts an electrostatic loudspeaker design, and the divergence angle of the main sound field is extremely small and the acoustic energy is coupled to the center by utilizing the traction and extrusion effects of the outer layer sound field, so that the main sound field is free from divergence and has small energy attenuation in the propagation process, and excitation sound is formed.
Preferably, the center of the multilayer annular sound field is a circular main sound wave generator, the outer-layer sound field is a multilayer annular structure sound field concentric with the main sound wave, and a transmission channel of the main sound wave is constructed so that the main sound wave is transmitted forwards under the extrusion of the outer sound field.
Preferably, the design principle of the electrostatic speaker is as follows: the audio input signal is sent to the magnet polar plate through the step-up transformer, and high voltage is applied between the magnet polar plate and the vibrating diaphragm; meanwhile, the vibrating diaphragm and the magnet polar plate are externally added with the sound wave resonant cavity, so that the generated sound wave generates standing waves under the action of the sound wave resonant cavity, and the sound wave is transmitted out through the meshes.
Preferably, the length of the acoustic wave resonant cavity is finely adjusted by the controller, the length of the acoustic wave resonant cavity is adjusted according to the wavelength of the main acoustic wave, and the total mesh area of the emitting surface of the resonant cavity needs to occupy more than 50% of the total area of the wave vibrating surface.
Preferably, the outer sound field is advanced by a fixed phase or frequency relative to the dominant sound field.
Preferably, the acoustic wave cavity length L is an integer multiple of half a wavelength of the dominant frequency of the audio signal.
The inventive laser generator will produce "directed sound waves" which are called "excitation sound" having at least basic properties like laser, such as excellent directivity of transmission, energy concentration, and no divergence. The excitation can be used in various fields, such as the field of underwater acoustic communication, so that the transmission distance of underwater acoustic signals can be increased, the confidentiality of transmission is improved, and the problem of energy consumption of the underwater sensor node is solved; in the field of acoustic detection, the accuracy and depth of sound wave or ultrasonic flaw detection can be improved; in the field of ultrasonic imaging, the accuracy of the acoustic scan can be improved.
Drawings
In order to more clearly illustrate the embodiments of the invention or the technical solutions in the prior art, the drawings that are required in the embodiments or the description of the prior art will be briefly described, it being obvious that the drawings in the following description are only some embodiments of the invention, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art. Wherein, the liquid crystal display device comprises a liquid crystal display device,
FIG. 1 is a schematic view of the structure of an excitation generator of the present invention;
FIG. 2 is a front view of the sound field of the excitation generator of the present invention;
fig. 3 is a schematic diagram of the electrostatic acoustic wave generator used in the inner and outer acoustic field generators.
Detailed Description
The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. Based on the embodiments of the present invention, all other embodiments that can be obtained by a person of ordinary skill in the art without making any inventive effort are within the scope of the present invention.
As shown in fig. 1, the present invention provides an excitation generator including:
an audio signal generator for generating a desired primary sound field audio signal;
the controller is used for adjusting the frequency and the power of the audio signal of the main sound field and the amplification factor of the audio signal;
and the display device is used for displaying the frequency of the current audio signal, the phase difference (or frequency difference) of the outer sound field and the signal output power information.
The audio signal generator is an inner layer sound field generator and an outer layer sound field generator with a multilayer annular sound field structure, the multilayer annular sound fields are all designed by adopting electrostatic loudspeakers, the divergence angle of the main sound field is extremely small by utilizing the traction and extrusion effects of the outer layer sound fields, and the sound wave energy is coupled to the center, so that the main sound field is not diverged in the transmission process, the energy attenuation is small, and the excitation sound is formed.
As shown in fig. 2, the middle of the audio signal generator is a primary sound field generator, which is mainly responsible for generating a primary sound field, the primary sound is used for transmitting or detecting sound waves, the communication system can be used as a sound wave carrier, the detection system is used as a primary detection sound wave, and the outer sound field mainly acts to ensure that the primary sound field is not diverged and transmitted forward. The outer sound field can be designed in one or more layers, certain coupling gaps are arranged between the multiple layers of sound fields for isolation, the gaps are made of rigid materials, the mutual interference between source generators is reduced, each sound field source adopts an electrostatic loudspeaker structural design (a central main sound field can adopt a traditional cone loudspeaker or sonar).
The multi-layer annular sound field design is adopted, the center is a circular main sound field generator, the outer-layer sound field is a multi-layer annular structure sound field (1 layer or multiple layers) concentric with the main sound wave, and a transmission channel of the main sound wave is constructed, so that the main sound wave is transmitted forwards under the extrusion of the outer-layer sound field.
Each layer adopts an electrostatic loudspeaker structure, so that the emitted sound field is as uniform as possible; and an additional sound wave resonant cavity is arranged, the distance L (shown in figure 3) between two planes of the resonant cavity is an integral multiple of half wavelength of the sound wave generator, the generated sound wave forms a standing wave, the sound pressure energy is increased again, and the emitting surface is designed into a mesh shape, so that the emitting surface is positioned at the antinode position with the maximum sound pressure, and the sound wave is sent out.
The extrusion of the outer sound field is used to make the internal main sound field form cylindrical wave surface in the transmission medium, and the initial power of plane wave is P 0 The power at a point in the transmission process is P, then P and P 0 The following relationship is provided:
plane wave: p=p 0 e -αx
P 0 Initial sound pressure of wave source
Where α is an attenuation coefficient, x is a transmission distance, and the wave attenuation of spherical waves and cylindrical waves can be represented by the following formula:
where P1 is the sound pressure at the distance of the wave source as a unit distance, it can be seen that forming cylindrical wave field propagation will effectively reduce the attenuation of the sound wave, and α can be expressed as: alpha = alpha s +α a
The structural design of the internal and external sound fields is adopted to reduce the diffusion attenuation of sound waves when the sound waves propagate in the medium.
Wherein:
where S is the wave source area, f is the acoustic frequency, c is a constant, and the amount is related to the density and viscosity of the medium.
Designing a driving circuit: the waveform phase difference of the outer sound field and the central main sound field is designed according to the rigidity of the transmission medium, so that the outer sound field leads the main sound field by a fixed phase value (the phase difference delta theta is related to the components of the transmission medium, the specific value is determined by experiments and can be called heterodyne phase detection for short), or the outer sound field frequency is higher than the main sound field frequency (the phase difference delta f is also related to the components of the transmission medium, and can be mainly used for sound wave transmission and detection in liquid or gas). This is another important key point of the present invention, the outer sound field must be advanced by a relatively fixed phase (Δθ) or higher than the inner sound field by a fixed frequency (Δf), so that the energy of the inner sound field is not lost, the divergence angle is small, and the energy of the outer sound field can be supplemented to the inner sound field under the same frequency.
The outer acoustic field is designed to be phased or higher than the inner acoustic field by a fixed frequency, primarily to combat the absorption loss of acoustic waves propagating in the medium, which is related to the viscosity of the medium, Δθ=k 1 c，Δf＝k 2 c, c is the stiffness index of the solid (or the viscosity coefficient of the liquid), k 1 ，k 2 The specific values may be determined experimentally for abnormalities, respectively.
As shown in fig. 3, the audio input signal is fed to the magnet plate via a step-up transformer, and a high voltage (500-600V) is applied between the magnet plate and the diaphragm. The audio input signal may be a single frequency, may be provided with a musical tone, or may be a modulated audio signal (such as a frequency modulated, amplitude modulated, or phase modulated audio signal). The vibrating diaphragm and the magnet polar plate are externally added with the sound wave resonant cavity, so that generated sound waves generate standing waves under the action of the resonant cavity, the booster sound pressure is improved, the length L of the resonant cavity is an integral multiple of half wavelength of the main frequency of an audio signal so as to form stable standing waves, the sound waves can be transmitted out through the design of the meshes, and the meshes are positioned at the place with the strongest sound pressure and transmit the sound waves. The length of the resonant cavity can be adjusted by the control of the controller, and the total mesh area of the emitting surface of the resonant cavity needs to be more than 50% of the total area of the wave vibrating surface.
The beneficial effects of the invention are as follows:
1. the main sound field can basically keep the field energy not to diverge under the extrusion of the outer sound wavelength, and the main sound field is transmitted forwards under the traction of the outer sound field due to the design that the outer sound field leads the inner main sound field, the energy of the main sound field is not diverged, and the outer sound field energy can be obtained through coupling, so that the main sound field can be ensured to have smaller energy consumption in the transmission process, the transmission distance of the main sound field sound wave is increased, and the laser sound similar to laser sound is formed. Such acoustic wave generators may be referred to as "excitation" generators.
2. The method has obvious benefits for the communication system taking the sound wave as the carrier wave, increases the transmission distance of the main carrier wave on one hand, improves the directivity of the main carrier wave on the other hand, and increases the confidentiality of information at the same time. From a communication point of view, "excitation" has excellent characteristics like "laser".
3. For an acoustic wave detection system using acoustic waves as detection purposes, such as an ultrasonic ranging system, an ultrasonic flaw detection system, an acoustic wave detection system and the like, the 'excitation' acoustic waves with good directivity can improve the detection precision of the system, meanwhile, the energy consumption of the system can be reduced, and an accurate detection result can be obtained by adopting lower power emission of a transmitter.
4. For a sensing system adopting sound waves to transmit information, such as an underwater sensing system, the accuracy and confidentiality of information transmission can be improved through good directionality of 'excitation sound', and meanwhile, the energy consumption is reduced, which is particularly important for an inconvenient detection system for supplying energy to the underwater sensing system.
5. For the medical system adopting the sound waves, the medical detection and treatment precision can be improved through the sound waves with good directivity, and the sound waves can penetrate through the human body, so that the sound waves are high in excitation energy and concentrated in direction, and can be used for fine operations such as tumor excision in the future without being prescribed on the body of a patient.
6. The static loudspeaker design is adopted in each layer of sound field, so that the plane uniformity of the sound field is improved, and meanwhile, the near field of sound waves is greatly reduced, so that the far field characteristics of the sound waves can be excellent.
7. The anti-interference performance of the main sound field is improved, the sound field adopts a layer-by-layer nested structural design, the outer sound field plays a certain role in protecting the inner sound field, and for a sound wave communication system, the parallel laminated sound field structure provides a new possibility for secret communication, and meanwhile, the outer sound field can also carry synchronous information, interval scheduling information and the like.
8. In the field of acoustic flaw detection, the angle theta is diverged by acoustic waves 0 ≈70λ/D S It can be seen that increasing the probe diameter D S The flaw detection frequency f and the half-diffusion angle theta are improved 0 The directivity of the sound beam can be improved by reducing, so that the energy of the ultrasonic wave is more concentrated, the flaw detection sensitivity is improved, and the divergence angle of the main sound wave is extremely small. And by the near-field length of the sound wave
It can be seen that increasing the probe diameter D S And the flaw detection frequency f is increased, the length of the near field area is increased, and flaw detection is not good. Therefore, in the actual flaw detection, D is comprehensively considered S And f is to theta 0 And the influence of N, reasonably select D S And f is generally to reduce the near field region length as much as possible while ensuring flaw detection sensitivity. The sound wave generator adopts an electrostatic loudspeaker structure, and the near and long distances can be reduced to a very small range, thereby being beneficial to improving the flaw detection precision. Thereby expanding the diameter D of the flaw detection probe S And selectable ranges of flaw detection acoustic wave frequencies f.
It will be apparent to those skilled in the art that various modifications and variations can be made to the present invention without departing from the spirit or scope of the invention. It should be noted that the above-mentioned embodiments are merely examples of the present invention, and are not intended to limit the invention, but all modifications and optimization within the spirit and scope of the present invention are included in the following claims.
Claims (2)
1. An excitation generator, comprising:
the audio signal generator is used for generating a required main sound field audio signal, and the audio signal generator is an inner sound field generator and an outer sound field generator with a multilayer annular sound field structure;
the controller is used for adjusting the frequency and the power of the audio signal of the main sound field and the amplification factor of the audio signal;
the display device is used for displaying the frequency of the current audio signal, the phase difference or the frequency difference of the outer sound field and the signal output power information;
wherein, each layer in the multilayer annular sound field structure adopts electrostatic loudspeaker design, the center of the multilayer annular sound field is a circular main sound wave generator, the outer layer sound field is a multilayer annular structure sound field concentric with the main sound wave, the multilayer sound fields are isolated by coupling gaps, and the gaps are made of rigid materials;
the design principle of the electrostatic loudspeaker is as follows: the audio input signal is sent to the magnet polar plate through the step-up transformer, and high voltage is applied between the magnet polar plate and the vibrating diaphragm; meanwhile, the vibrating diaphragm and the magnet polar plate are externally provided with an acoustic wave resonant cavity, so that generated acoustic waves generate standing waves under the action of the acoustic wave resonant cavity, and the acoustic waves are transmitted out through meshes;
the outer sound field is advanced by a fixed phase or frequency from the primary sound field;
the length L of the acoustic wave resonant cavity is an integral multiple of half wavelength of the main frequency of the audio signal.
2. The excitation generator of claim 1, wherein the acoustic wave cavity length is tuned by the controller, the acoustic wave cavity length being adjusted based on the wavelength of the primary acoustic wave, the total mesh area of the cavity emitting surface accounting for greater than 50% of the total area of the wave vibrating surface.
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| EP0457487A2 (en) * | 1990-05-18 | 1991-11-21 | Matsushita Electric Industrial Co., Ltd. | Horn speaker |
| CN2792070Y (en) * | 2005-05-14 | 2006-06-28 | 深圳东原电子有限公司 | High pitch loudspeaker with multiway diffusion function |
| CN110784799A (en) * | 2019-10-29 | 2020-02-11 | 中国电子科技集团公司第四十一研究所 | Sound directional transmission method and system |
| CN111818422A (en) * | 2020-07-03 | 2020-10-23 | 电子科技大学 | Fixed-point sound wave transmitting device based on parametric array principle |
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| CN2812462Y (en) * | 2005-04-19 | 2006-08-30 | 北京马斯康电子有限公司 | Resonance frequency-selection piezoelectric loudspeaker |
| US8081775B2 (en) * | 2007-03-09 | 2011-12-20 | Robert Bosch Gmbh | Loudspeaker apparatus for radiating acoustic waves in a hemisphere around the centre axis |
| CN102651843B (en) * | 2012-02-23 | 2014-07-23 | 北京航天计量测试技术研究所 | Standing wave pipe coupling cavity used for wide-band low-distortion equal-amplitude equal-phase calibration |
| CN104090031B (en) * | 2014-07-16 | 2016-05-11 | 浙江省交通规划设计研究院 | A kind of pumping of prostressed duct quality detection device based on Ultrasonic Annular Phased Arrays |
| CN107755230A (en) * | 2017-11-16 | 2018-03-06 | 中国计量大学 | The controllable high power altrasonic transducer of sound field |
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| CN109261472B (en) * | 2018-08-30 | 2019-11-08 | 西安交通大学 | A kind of generation device and method of space-focusing vortex sound field |
| CN111130500A (en) * | 2019-11-08 | 2020-05-08 | 中北大学 | Surface acoustic wave device and design method thereof |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0457487A2 (en) * | 1990-05-18 | 1991-11-21 | Matsushita Electric Industrial Co., Ltd. | Horn speaker |
| CN2792070Y (en) * | 2005-05-14 | 2006-06-28 | 深圳东原电子有限公司 | High pitch loudspeaker with multiway diffusion function |
| CN110784799A (en) * | 2019-10-29 | 2020-02-11 | 中国电子科技集团公司第四十一研究所 | Sound directional transmission method and system |
| CN111818422A (en) * | 2020-07-03 | 2020-10-23 | 电子科技大学 | Fixed-point sound wave transmitting device based on parametric array principle |
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