CN110856070B - Initiative sound insulation earmuff that possesses pronunciation enhancement function - Google Patents
Initiative sound insulation earmuff that possesses pronunciation enhancement function Download PDFInfo
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- CN110856070B CN110856070B CN201911142904.7A CN201911142904A CN110856070B CN 110856070 B CN110856070 B CN 110856070B CN 201911142904 A CN201911142904 A CN 201911142904A CN 110856070 B CN110856070 B CN 110856070B
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- 238000009413 insulation Methods 0.000 title claims abstract description 32
- 101001010782 Drosophila melanogaster Fez family zinc finger protein erm Proteins 0.000 claims abstract description 38
- 230000030279 gene silencing Effects 0.000 claims abstract description 6
- 238000001914 filtration Methods 0.000 claims abstract description 5
- 230000005236 sound signal Effects 0.000 claims description 10
- 230000005284 excitation Effects 0.000 claims description 6
- 230000003044 adaptive effect Effects 0.000 claims description 5
- 230000003750 conditioning effect Effects 0.000 claims description 5
- 230000003321 amplification Effects 0.000 claims description 3
- 238000003199 nucleic acid amplification method Methods 0.000 claims description 3
- 239000010985 leather Substances 0.000 claims description 2
- 230000008030 elimination Effects 0.000 claims 1
- 238000003379 elimination reaction Methods 0.000 claims 1
- 230000002708 enhancing effect Effects 0.000 claims 1
- 230000006870 function Effects 0.000 abstract description 7
- 238000004891 communication Methods 0.000 abstract description 6
- 239000000284 extract Substances 0.000 abstract description 5
- 238000005516 engineering process Methods 0.000 abstract description 4
- 210000005069 ears Anatomy 0.000 abstract description 3
- 238000010586 diagram Methods 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 238000003491 array Methods 0.000 description 2
- 230000005764 inhibitory process Effects 0.000 description 2
- 238000002955 isolation Methods 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 230000026683 transduction Effects 0.000 description 2
- 238000010361 transduction Methods 0.000 description 2
- 230000007547 defect Effects 0.000 description 1
- 238000010030 laminating Methods 0.000 description 1
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- 230000002194 synthesizing effect 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
- H04R1/10—Earpieces; Attachments therefor ; Earphones; Monophonic headphones
- H04R1/1083—Reduction of ambient noise
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- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
- A61F11/00—Methods or devices for treatment of the ears or hearing sense; Non-electric hearing aids; Methods or devices for enabling ear patients to achieve auditory perception through physiological senses other than hearing sense; Protective devices for the ears, carried on the body or in the hand
- A61F11/06—Protective devices for the ears
- A61F11/14—Protective devices for the ears external, e.g. earcaps or earmuffs
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- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
- A61F11/00—Methods or devices for treatment of the ears or hearing sense; Non-electric hearing aids; Methods or devices for enabling ear patients to achieve auditory perception through physiological senses other than hearing sense; Protective devices for the ears, carried on the body or in the hand
- A61F11/06—Protective devices for the ears
- A61F11/14—Protective devices for the ears external, e.g. earcaps or earmuffs
- A61F11/145—Protective devices for the ears external, e.g. earcaps or earmuffs electric, e.g. for active noise reduction
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- Engineering & Computer Science (AREA)
- Acoustics & Sound (AREA)
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- Psychology (AREA)
- Biophysics (AREA)
- Otolaryngology (AREA)
- Biomedical Technology (AREA)
- Heart & Thoracic Surgery (AREA)
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Abstract
The invention discloses an active sound insulation earmuff with a voice enhancement function, which comprises earmuffs with high passive sound insulation performance; the microphone pickup circuit is used for collecting external environment noise and voice signals and collecting error noise in the ear muff cavity; the microprocessor control circuit extracts a voice signal and synthesizes an anti-noise signal; the audio driving and power amplifying circuit is used for reconstructing, filtering and power amplifying the voice signal and the anti-noise signal; and the silencing loudspeaker is used for emitting anti-noise and outputting a voice signal at the same time. On the basis that the passive sound insulation earmuffs isolate most high-frequency noise, the low-frequency noise is inhibited near the ears of people through an active noise reduction technology, and meanwhile, voice signals are extracted through the microphone array arranged outside the earmuffs and combined with an array voice enhancement algorithm, coupled into an active noise reduction system and input into the earmuff cavity, so that the more effective hearing protection is realized, the voice intelligibility among wearers is improved, and the normal voice communication is ensured.
Description
Technical Field
The invention relates to the technical field of hearing protection and voice enhancement, in particular to an active sound insulation earmuff with a voice enhancement function.
Background
In a strong noise industrial site, low frequency noise pollution is particularly prominent, and field personnel generally wear physical sound-insulating earmuffs for hearing protection. The existing professional sound insulation earmuffs have excellent physical sound insulation performance only reflected in the isolation of high-frequency noise, but have extremely limited isolation effect on low-frequency noise.
In order to improve the sound insulation performance of the earmuffs in full frequency bands, active noise reduction technology needs to be combined. But the ear muff that has the initiative function of making an uproar of falling at present can weaken the shielding with normal human sound together with ambient sound, does not consider the relation of the outer sound of wearer and ear muff, can not guarantee the speech communication between the wearer under the strong noise environment. There is a need for further improvements in existing acoustical earmuffs.
Disclosure of Invention
The purpose of the invention is as follows: the invention aims to provide an active sound insulation earmuff with a voice enhancement function aiming at the defects of the prior art, so that normal voice communication among wearers is ensured while hearing protection is provided for the wearers in a strong noise environment.
The technical scheme is as follows: the invention discloses an active sound insulation earmuff with a voice enhancement function, which comprises:
the earmuffs with high passive sound insulation performance are used for passively isolating high-frequency noise outside the earmuffs;
the microphone pickup circuit comprises two groups of signal conditioning circuits which are respectively positioned inside and outside the earmuffs and used for sound signal transduction processing, and a microphone array pickup circuit is externally arranged and used for collecting external environment noise and voice signals; an error microphone pickup circuit is arranged in the earmuff and is used for collecting error noise in the cavity of the earmuff;
the microprocessor control circuit extracts and enhances the voice signals collected by the microphone pickup microphone circuit, and synthesizes anti-noise signals by taking the collected external environment noise as a reference signal; sending the enhanced voice signal and the synthesized anti-noise signal to an audio driving and power amplifying circuit;
the audio driving and power amplifying circuit is used for carrying out reconstruction filtering and power amplification on the voice signal and the anti-noise signal and then sending the voice signal and the anti-noise signal to the silencing loudspeaker;
and the silencing loudspeaker is used for sending out the interference cancellation of the anti-noise and the noise in the ear muffs and outputting the voice signal.
A further preferable technical solution of the present invention is that the microphone array pickup circuit includes a microphone array, the microphone array is composed of two or more microphones, and a sound signal picked up by one microphone in the microphone array is used as a reference signal for active noise reduction; and the other microphones of the microphone array are combined with a voice enhancement algorithm to extract voice signals to serve as excitation signals for online identification of secondary channels in the active noise reduction system.
Preferably, the microprocessor control circuit comprises a microcontroller, an ADC interface and a DAC interface;
a system identification algorithm is embedded into the microcontroller, the physical sound insulation structure of the earmuff is estimated and identified, an earmuff passive sound insulation structure estimation model is constructed, external environment noise collected by the microphone array is filtered by the model and then is used as a reference signal, and an anti-noise signal is synthesized; the embedded microphone array speech enhancement algorithm extracts a speech signal, and the speech signal is used as an excitation signal for online identification of a secondary channel in the active noise reduction system; the method is used for embedding an adaptive active noise reduction algorithm to synthesize an anti-noise signal;
the ADC interface is used for being connected with a microphone pickup microphone circuit and driving the microphone array to pick up sound and sample;
and the DAC interface is used for outputting audio signals and is connected with the audio driving and power amplifying circuit.
Preferably, the microprocessor embedded active noise reduction algorithm employs a feedforward digital noise reduction topology.
Preferably, the high passive sound-proof performance ear muff comprises a sound-proof cavity and a sound-absorbing sponge, and is wrapped by a leather ear cap and attached to the auricle.
Has the advantages that: the invention is an earmuff which combines active noise reduction and passive noise reduction and ensures normal voice communication between wearers under the strong noise environment, when the active sound insulation earmuff isolates strong noise, a microphone array is used for extracting voice signals, the extracted voice signals are coupled into an active noise reduction system, and finally the extracted voice signals are kept in the cavity of the earmuff and are not counteracted and inhibited; on the basis that the passive sound insulation earmuffs isolate most high-frequency noise, the low-frequency noise is inhibited near the ears of people through an active noise reduction technology, and meanwhile, voice signals are extracted through the microphone array arranged outside the earmuffs and combined with an array voice enhancement algorithm, coupled into an active noise reduction system and input into the earmuff cavity, so that the noise inhibition effect in a low-frequency broadband range can be improved, more effective hearing protection is realized, the voice intelligibility among wearers is improved, and normal voice communication is ensured.
Drawings
Fig. 1 is a schematic block diagram of an earmuff of the present invention.
Fig. 2 is a system block diagram of the earmuff of the present invention.
Fig. 3 is a block diagram of the earmuff of the present invention.
Detailed Description
The technical solution of the present invention is described in detail below with reference to the accompanying drawings, but the scope of the present invention is not limited to the embodiments.
Example (b): the utility model provides an ear muff gives sound insulation of initiative that possesses pronunciation enhancement function for guarantee the normal pronunciation of personnel and exchange when protecting the hearing under the strong noise environment, when the strong noise is kept apart to the ear muff that gives sound insulation of initiative, utilize the microphone array to extract speech signal, and couple the speech signal who extracts to the noise reduction system of initiative, finally remain in the ear muff cavity and not offset the suppression. It mainly comprises:
high passive sound-proof performance ear muff constitutes the main part by the cavity that gives sound insulation with inhale the sound sponge to the laminating of parcel cortex earmuff is at the auricle, is used for the outer high frequency noise of passive isolated ear muff.
The microphone pickup circuit comprises two groups of signal conditioning circuits which are respectively positioned inside and outside the earmuffs and used for sound signal transduction processing, and the microphone pickup circuit is externally arranged and comprises a microphone array consisting of two or more microphones, and a sound signal picked up by one microphone in the microphone array is used as a reference signal for active noise reduction; combining the rest microphones of the microphone array with a voice enhancement algorithm, and extracting a voice signal as an excitation signal for online identification of a secondary channel in the active noise reduction system; the built-in error microphone pickup circuit for gather the error noise in the ear muff cavity, the error noise is used for updating the control filter weight.
The microprocessor control circuit comprises a microcontroller, an ADC interface and a DAC interface;
a system identification algorithm is embedded into the microcontroller, the physical sound insulation structure of the earmuff is estimated and identified, an estimation model of the passive sound insulation structure of the earmuff is constructed, and external environment noise collected by the microphone array is filtered by the model and then is used as a reference signal; the embedded microphone array speech enhancement algorithm extracts a speech signal, and the speech signal is used as an excitation signal for online identification of a secondary channel in the active noise reduction system; the method is used for embedding a self-adaptive active noise reduction algorithm, and synthesizing an anti-noise signal by taking the collected external environment noise as a reference signal;
the ADC interface is used for being connected with a microphone pickup microphone circuit and driving the microphone array to pick up sound and sample;
and the DAC interface is used for outputting audio signals and is connected with the audio driving and power amplifying circuit.
And the audio driving and power amplifying circuit is used for carrying out reconstruction filtering and power amplification on the voice signal and the anti-noise signal and then sending the voice signal and the anti-noise signal to the silencing loudspeaker.
And the silencing loudspeaker is used for sending out the interference cancellation of the anti-noise and the noise in the ear muffs and outputting the voice signal.
The working principle of the invention is as follows:
according to the self-adaptive system identification principle, the passive sound insulation structure of the earmuffs with high passive sound insulation performance is identified and modeled through the microprocessor, and an estimation model of the passive sound insulation structure is obtained and stored in the microprocessor; when strong noise containing voice signals outside the earmuffs enters the earmuffs, most high-frequency noise is isolated by the passive sound insulation structure of the earmuffs, mainly low-frequency noise components enter the cavities of the earmuffs, and then the low-frequency noise is counteracted and suppressed by the active noise reduction system; one of the microphone arrays is used as a reference signal acquisition microphone in the active noise reduction system, and before the reference signal is injected into the adaptive filter to synthesize anti-noise, filtering processing is carried out through an ear shield passive sound insulation structure estimation model, so that high-frequency noise isolated by the ear shield passive sound insulation structure is prevented from being introduced into an ear shield cavity again; the sound signals collected by the microphone array are subjected to voice enhancement algorithm to extract voice signals, and the voice signals are used as excitation signals of secondary channels in the active noise reduction system for online self-adaptive identification, and the voice signals are directly injected into the earmuff cavity.
The invention utilizes the principle of active and passive mixed noise reduction and the principle of microphone array voice enhancement, on the basis that the passive sound insulation earmuffs isolate most high-frequency noise, the low-frequency noise is inhibited near the ears of people through the active noise reduction technology, and meanwhile, the voice signals are extracted by arranging the microphone arrays outside the earmuffs and combining with the array voice enhancement algorithm, coupled into the active noise reduction system and input into the earmuff cavity, so that the noise inhibition effect in the low-frequency broadband range can be improved, more effective hearing protection is realized, the voice intelligibility among wearers is improved, and normal voice communication is ensured.
As noted above, while the present invention has been shown and described with reference to certain preferred embodiments, it is not to be construed as limited thereto. Various changes in form and detail may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.
Claims (3)
1. An active acoustic earmuff with speech enhancement, comprising:
the ear muffs have passive sound insulation performance and are used for passively isolating high-frequency noise outside the ear muffs;
the microphone pickup microphone circuit comprises two groups of signal conditioning circuits which are respectively positioned inside and outside the earmuffs, and the external signal conditioning circuit is a microphone array pickup circuit and is used for collecting sound signals which comprise external environment noise and voice signals; the built-in signal conditioning circuit is an error microphone pickup circuit and is used for collecting error noise in the cavity of the ear muff;
the microphone array pickup circuit comprises a microphone array, wherein the microphone array consists of two or more microphones;
the microprocessor control circuit comprises a microprocessor, an ADC interface and a DAC interface; the adaptive system identification algorithm embedded in the microprocessor is used for estimating and identifying a physical sound insulation structure of the earmuffs and constructing a passive sound insulation structure estimation model of the earmuffs, and a sound signal picked up by one microphone in the microphone array is filtered by the passive sound insulation structure estimation model and then is used as a reference signal; an adaptive active noise reduction algorithm embedded in the microprocessor synthesizes an anti-noise signal of the active noise reduction system according to the reference signal;
the microphone array voice enhancement algorithm is embedded in the microprocessor and used for extracting voice signals in sound signals picked up by other microphones of the microphone array and taking the voice signals as excitation signals of secondary channel online identification in the active noise reduction system;
the ADC interface is used for being connected with a microphone pickup circuit;
the DAC interface is used for being connected with the audio driving and power amplifying circuit;
the microprocessor control circuit is used for extracting and enhancing the voice signal collected by the microphone pickup circuit and sending the enhanced voice signal and the synthesized anti-noise signal to the audio driving and power amplifying circuit;
the audio driving and power amplifying circuit is used for carrying out reconstruction filtering and power amplification on the enhanced voice signal and the synthesized anti-noise signal and then sending the voice signal and the synthesized anti-noise signal to the noise elimination loudspeaker;
and the silencing loudspeaker is used for sending out anti-noise to be destructively interfered with noise in the ear muffs and outputting the enhanced voice signal.
2. The active acoustic earmuff with speech enhancement of claim 1, wherein the adaptive active noise reduction algorithm embedded in the microprocessor employs a feedforward digital noise reduction topology.
3. The active acoustic earmuff with voice enhancement function according to claim 1, wherein the earmuff comprises a main body consisting of an acoustic cavity and an acoustic sponge, and is wrapped by a leather earmuff.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201911142904.7A CN110856070B (en) | 2019-11-20 | 2019-11-20 | Initiative sound insulation earmuff that possesses pronunciation enhancement function |
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| CN201911142904.7A CN110856070B (en) | 2019-11-20 | 2019-11-20 | Initiative sound insulation earmuff that possesses pronunciation enhancement function |
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| CN110856070A CN110856070A (en) | 2020-02-28 |
| CN110856070B true CN110856070B (en) | 2021-06-25 |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN112869945A (en) * | 2021-01-11 | 2021-06-01 | 杭州师范大学 | Noise nature hearing loss protection device |
| CN113080928A (en) * | 2021-03-30 | 2021-07-09 | 上海联影医疗科技股份有限公司 | Active noise reduction system and medical equipment with same |
| CN116439913B (en) * | 2023-04-14 | 2024-03-15 | 中国人民解放军海军潜艇学院 | Marine active hearing protection type earmuff and protection method thereof |
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| CN106792316A (en) * | 2017-01-10 | 2017-05-31 | 南京航空航天大学 | A kind of industrial active noise reduction earmuff |
| CN106878851A (en) * | 2017-03-17 | 2017-06-20 | 浙江大学 | A kind of active noise reduction earphone based on channel compensation Yu speech recognition |
| CN110447073A (en) * | 2017-03-20 | 2019-11-12 | 伯斯有限公司 | Audio Signal Processing for noise reduction |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US10484792B2 (en) * | 2018-02-16 | 2019-11-19 | Skullcandy, Inc. | Headphone with noise cancellation of acoustic noise from tactile vibration driver |
| CN110099323B (en) * | 2019-05-23 | 2021-04-23 | 歌尔科技有限公司 | Active noise reduction earphone |
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Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102077607A (en) * | 2008-05-02 | 2011-05-25 | Gn奈康有限公司 | A method of combining at least two audio signals and a microphone system comprising at least two microphones |
| CN106254989A (en) * | 2016-08-31 | 2016-12-21 | 宁波浙大电子有限公司 | A kind of noise cancelling headphone and noise-reduction method thereof |
| CN106792316A (en) * | 2017-01-10 | 2017-05-31 | 南京航空航天大学 | A kind of industrial active noise reduction earmuff |
| CN106878851A (en) * | 2017-03-17 | 2017-06-20 | 浙江大学 | A kind of active noise reduction earphone based on channel compensation Yu speech recognition |
| CN110447073A (en) * | 2017-03-20 | 2019-11-12 | 伯斯有限公司 | Audio Signal Processing for noise reduction |
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