CN110446146A - Smart speakers - Google Patents
Smart speakers Download PDFInfo
- Publication number
- CN110446146A CN110446146A CN201910726754.8A CN201910726754A CN110446146A CN 110446146 A CN110446146 A CN 110446146A CN 201910726754 A CN201910726754 A CN 201910726754A CN 110446146 A CN110446146 A CN 110446146A
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- Prior art keywords
- amplifier
- noise
- voltage
- audio
- signal
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- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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- 230000007613 environmental effect Effects 0.000 claims abstract description 17
- 238000004458 analytical method Methods 0.000 claims abstract description 13
- 230000003321 amplification Effects 0.000 claims abstract description 11
- 238000003199 nucleic acid amplification method Methods 0.000 claims abstract description 11
- 230000005236 sound signal Effects 0.000 claims description 13
- 230000005611 electricity Effects 0.000 claims description 4
- 238000010586 diagram Methods 0.000 description 4
- 238000000034 method Methods 0.000 description 4
- 230000000694 effects Effects 0.000 description 3
- 238000000540 analysis of variance Methods 0.000 description 2
- 230000002093 peripheral effect Effects 0.000 description 2
- 239000003990 capacitor Substances 0.000 description 1
- 230000007812 deficiency Effects 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 230000009977 dual effect Effects 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 238000000746 purification Methods 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 230000001360 synchronised effect Effects 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03G—CONTROL OF AMPLIFICATION
- H03G3/00—Gain control in amplifiers or frequency changers without distortion of the input signal
- H03G3/20—Automatic control
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
- H04R9/00—Transducers of moving-coil, moving-strip, or moving-wire type
- H04R9/06—Loudspeakers
Landscapes
- Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Acoustics & Sound (AREA)
- Signal Processing (AREA)
- Circuit For Audible Band Transducer (AREA)
- Soundproofing, Sound Blocking, And Sound Damping (AREA)
Abstract
The invention belongs to loudspeaker fields, in particular to its volume can adapt to the novel intelligent loudspeaker of ambient noise fluctuating automatically.Smart speakers, it includes the power supply module being powered for each unit, audio voltage controllable amplifier for controllably amplifying to audio voltage, audio voltage controllable amplifier power amplifier, it is characterized by also including for exporting audio and environmental noise can be converted to the speaker drive voice coil of electric signal, and the noise analysis processing component being connect with speaker drive voice coil, noise analysis processing component output noise voltage signal gives audio voltage controllable amplifier, audio voltage controllable amplifier adjusts the amplification factor to audio voltage according to noise voltage signal, realization speaker volume adjust automatically with the variation of environmental noise.
Description
Technical field
The invention belongs to loudspeaker fields, in particular to its volume can adapt to the novel intelligence of ambient noise fluctuating automatically
It can loudspeaker.
Background technique
At home and abroad loudspeaker has a single function only as a kind of device that electric signal is changed into acoustical signal at present.
Due to the unicity of existing loudspeaker function, in the biggish environment of every profession and trade noise bounce, output volume without
Method realizes automatic, real-time, synchronous adjustment, is greatly affected broadcast/calling effect: exporting constant volume in loudspeaker
In the case where, when ambient noise increases, broadcast/ring tone can not hear clearly；Noise hour, broadcast/ring tone again can be to peripheries
Cause biggish interference in space.It is improved for this reason, it may be necessary to carry out intelligent innovation to conventional speakers.
Summary of the invention
In view of the deficiencies of the prior art, the present invention provides a kind of loudspeaker that noise robustness is high.Intelligence of the present invention
Energy loudspeaker has the function of adapting to ambient noise fluctuating automatically, meets and guarantee signal/noise ratio under noise bounce environmental condition
Requirement.
Technical scheme is as follows:
Smart speakers comprising be the power supply module that each unit is powered, for controllably amplifying to audio voltage
Audio voltage controllable amplifier, audio voltage controllable amplifier power amplifier, it is characterised in that: further include for exporting
Audio and the speaker drive voice coil that environmental noise can be converted to electric signal, and make an uproar with what speaker drive voice coil was connect
Cent analyses processing component, and noise analysis processing component output noise voltage signal gives audio voltage controllable amplifier, audio voltage
Controllable amplifier adjusts the amplification factor to audio voltage according to noise voltage signal, realizes speaker volume with environmental noise
Change and adjust automatically.
Further, the noise analysis processing component includes carrying out sound to the signal that speaker drive voice coil provides
Frequency signal and the identification of noise signal and isolated letter/grid current of making an uproar device believe/make an uproar that grid current device is connected with noise processor, at noise
Complicated noise signal is processed into control voltage by reason device, and noise processor is connected with control voltage amplifier, and control voltage is put
Big device amplifies the control voltage that noise processor exports, and finally controls voltage amplifier and passes to amplified voltage
Audio voltage controllable amplifier.
Further, the audio voltage controllable amplifier, which is connected with, converts acoustic signals into weak audio electric signal
Broadcast/calling transmitter.
Further, the audio voltage of input is carried out distortionless power amplification by the power amplifier.
Further, the letter/grid current of making an uproar device includes for receiving the signal from speaker drive voice coil
One emitter follower and the second emitter follower for receiving the signal from audio voltage controllable amplifier, the second emitter follower are connected with reverse phase
Amplifier, inverting amplifier and the first emitter follower are connect with differential amplifier, differential amplifier output noise signal to noise at
Manage device.
Further, the noise processor include and believe/make an uproar grid current device connection low-pass filter circuit, low pass filtered
Wave circuit is connected with amplitude limiter circuit, and amplitude limiter circuit is connected with amplifier integrating circuit, amplifier integrating circuit and control voltage amplifier
Connection.
Further, the audio voltage controllable amplifier includes for receiving making an uproar from control voltage amplifier
Sound voltage signal and receiving are from the preset operational amplifier circuit for allowing noise voltage signal of power supply module, operational amplifier circuit connection
There is audio voltage amplifier, audio voltage amplifier is according to operational amplifier circuit gain-controlled voltage to the multiple of audio voltage amplifier
It is adjusted.
In conclusion the invention has the following advantages:
1, speaker drive voice coil of the invention has the function of to turn environmental noise while output audio signal
Change the function of electric signal into, noise analysis processing component carries out point analysis of variance simultaneously to the electric signal that speaker drive voice coil generates
One noise electric signal of final output gives audio voltage controllable amplifier, audio voltage controllable amplifier according to noise electric signal come
The amplification factor to audio signal is adjusted, so that loudspeaker output volume size can be adjusted according to environmental noise by realizing
Purpose.
2, it present invention accomplishes ensuring broadcast/calling effect in noise fluctuating environment, and minimizes in noise hour
The requirement of larger interference is caused to peripheral space.
Detailed description of the invention
Fig. 1 is composition schematic diagram of the invention；
Fig. 2 is the composition schematic diagram road for believing/making an uproar grid current device；
Fig. 3 is the composition schematic diagram of noise processor；
Fig. 4 is the composition schematic diagram of audio voltage controllable amplifier；
Specific embodiment
In order to make the object, technical scheme and advantages of the embodiment of the invention clearer, below in conjunction with the embodiment of the present invention
Attached drawing, the technical solution of the embodiment of the present invention is clearly and completely described.Obviously, described embodiment is this hair
Bright a part of the embodiment, instead of all the embodiments.Based on described the embodiment of the present invention, ordinary skill
Personnel's every other embodiment obtained under the premise of being not necessarily to creative work, shall fall within the protection scope of the present invention.
As shown in Figure 1, smart speakers comprising be the power supply module 1 that each unit is powered, to the correlation of composition
Part centrally connected power supply；Audio voltage controllable amplifier 2 for controllably amplifying to audio voltage, audio voltage controllable amplifier 2
Power amplifier 3, it is characterised in that: further include for exporting audio and environmental noise can be converted to the loudspeaking of electric signal
Device driving voice coil 4, and the noise analysis processing component 5 connecting with speaker drive voice coil 4, noise analysis processing component 5 are defeated
Noise voltage signal is to audio voltage controllable amplifier 2 out, and audio voltage controllable amplifier 2 is according to the adjustment pair of noise voltage signal
The amplification factor of audio voltage, realization speaker volume adjust automatically with the variation of environmental noise.
The speaker drive voice coil of the present embodiment pair has dual function, and function one: broadcast/calling electric signal is converted into
Acoustical signal；Function two: acquiring the signal of environmental noise, forms faint noise electric signal；Detailed process is as follows: external environment is made an uproar
Sound makes speaker drive voice coil do cutting magnetic line movement in loudspeaker fixed magnetic field, in loudspeaker by diffuser
In the motion process for driving voice coil, the driving voice coil of loudspeaker can generate noise current output；I.e. while broadcast or calling
The detection to environmental noise is completed, the noise electric signal for detecting generation obtains one after the processing of noise analysis processing component
A noise voltage signal, noise voltage signal feed back to audio voltage controllable amplifier, and audio voltage controllable amplifier is according to making an uproar
The size of sound voltage signal adjusts broadcast/calling electric signal amplification factor, thus realize the acoustical signal of loudspeaker output
The adjustment of volume, the present embodiment realize the smart speakers of the size adjust automatically output volume size according to environmental noise.
Further, the noise analysis processing component 5 includes carrying out to the signal that speaker drive voice coil provides
Audio signal and the identification of noise signal and isolated letter/grid current of making an uproar device 50, believe/make an uproar that grid current device 50 is connected with noise processor
51, complicated noise signal is processed into control voltage by noise processor 51, and noise processor 51 is connected with control voltage amplification
Device 52, control voltage amplifier amplify the control voltage that noise processor exports, and finally controlling voltage amplifier will put
Voltage after big passes to audio voltage controllable amplifier, the letter with environmental noise in the signal that speaker drive voice coil provides
Number and itself output acoustical signal audio signal, it is necessary to carrying out separation to the two just can be carried out accurate adjustment, therefore believes/makes an uproar
For separating to noise signal and audio signal, the electric signal generated to speaker drive voice coil carries out at purification grid current device
Reason；Obtained noise electric signal enters noise processor, and noise treatment handles noise electric signal, and is converted into control electricity
Pressure since the control voltage of noise processor output is smaller, therefore needs to amplify by control voltage amplifier, and finally pass
Pass audio voltage controllable amplifier.
The audio voltage controllable amplifier 2 includes for receiving the noise voltage signal from control voltage amplifier
And receive from the preset operational amplifier circuit 20 for allowing noise voltage signal of power supply module, operational amplifier circuit 20 is connected with audio
Voltage amplifier 21, audio voltage amplifier are carried out according to multiple of the operational amplifier circuit gain-controlled voltage to audio voltage amplifier
Adjustment；Next 2 principle of audio voltage controllable amplifier is illustrated:
Principle: voltage signal Vs and power supply module of the operational amplifier circuit receiving from control voltage amplifier provide for it
Preset reference voltage Vr, reference voltage Vr are the noise voltage of presetting permission, when voltage signal Vs is greater than setting
Reference voltage Vr when, the control of operational amplifier circuit output gain voltage Vc give audio voltage amplifier, and audio voltage amplifier receives
From broadcast/calling transmitter audio signal, audio voltage amplifier proposes audio signal according to gain-controlled voltage automatically
For gain；When voltage signal Vs be less than setting reference voltage Vr when, operational amplifier circuit will not output gain control voltage Vc, audio
Voltage amplifier is amplified by normality gain.
The audio voltage controllable amplifier 2, which is connected with, converts acoustic signals into the broadcast of weak audio electric signal/exhale
It is transmitter 6, acoustical signal is changed into ultra-weak electronic signal.
The audio voltage of input is carried out distortionless power amplification by the power amplifier.
Further, as shown in Fig. 2, the letter/grid current of making an uproar device 50 includes coming from speaker drive sound for receiving
First emitter follower of the signal of circle and the second emitter follower for receiving the signal from audio voltage controllable amplifier, the second emitter following
Device is connected with inverting amplifier, and inverting amplifier and the first emitter follower are connect with differential amplifier, differential amplifier output noise
Signal is to noise processor, and herein to believing/make an uproar that the principle of grid current device makes explanations: the first emitter follower receives from speaker drive
The signal of voice coil, including external audio signal and noise signal, the second emitter follower receives controllably to put from audio voltage
The audio signal of big device, audio signal is transmitted to progress reverse phase processing in inverting amplifier by the second emitter follower, then differential
It is conjugated principle of cancellation using positive negative signal in amplifier, obtains the collected noise signal of speaker drive voice coil.
Further, as shown in figure 3, the noise processor 51 include and believe/make an uproar grid current device connection low pass filtered
Wave circuit, low-pass filter circuit are connected with amplitude limiter circuit, and amplitude limiter circuit is connected with amplifier integrating circuit, amplifier integrating circuit and control
Voltage amplifier connection processed, make explanations herein to the principle of noise processor: low-pass filter circuit is utilized and is sent out altogether in triode
The mode of capacitor is connected in parallel in emitter-base bandgap grading amplifying circuit collector resistor, the function of Lai Shixian low frequency noise output changes
Collector resistor resistance value and condenser capacity size achieve the purpose that end 5000Hz or more high frequency noise, low-pass filtering electricity
Amplitude limiter circuit of the noise signal that road provides through being constituted by a diode carries out amplitude limiting processing, is finally formed and is controlled through amplifier integrating circuit
Voltage processed.
In conclusion the invention has the following advantages:
1, speaker drive voice coil of the invention has the function of to turn environmental noise while output audio signal
Change the function of electric signal into, noise analysis processing component carries out point analysis of variance simultaneously to the electric signal that speaker drive voice coil generates
One noise electric signal of final output gives audio voltage controllable amplifier, audio voltage controllable amplifier according to noise electric signal come
The amplification factor to audio signal is adjusted, so that loudspeaker output volume size can be adjusted according to environmental noise by realizing
Purpose.
2, it present invention accomplishes ensuring broadcast/calling effect in noise fluctuating environment, and minimizes in noise hour
The requirement of larger interference is caused to peripheral space.
Claims (7)
1. smart speakers comprising be the power supply module that each unit is powered, for what is controllably amplified to audio voltage
Audio voltage controllable amplifier, audio voltage controllable amplifier power amplifier, it is characterised in that: further include for exporting sound
Frequency and the speaker drive voice coil that environmental noise can be converted to electric signal, and the noise being connect with speaker drive voice coil
Processing component is analyzed, noise analysis processing component output noise voltage signal gives audio voltage controllable amplifier, and audio voltage can
Amplification factor of the amplifier according to the adjustment of noise voltage signal to audio voltage is controlled, realizes speaker volume with the change of environmental noise
Change and adjust automatically.
2. smart speakers according to claim 1, it is characterised in that: the noise analysis processing component includes to raising
The signal that sound device drives voice coil to provide carries out audio signal and the identification of noise signal and isolated letter/grid current of making an uproar device, believes/make an uproar grid
Stream device is connected with noise processor, and complicated noise signal is processed into control voltage, noise processor connection by noise processor
There is control voltage amplifier, control voltage amplifier amplifies the control voltage that noise processor exports, finally control electricity
Press amplifier that amplified voltage is passed to audio voltage controllable amplifier.
3. smart speakers according to claim 1, it is characterised in that: the audio voltage controllable amplifier is connected with
Convert acoustic signals into broadcast/calling transmitter of weak audio electric signal.
4. smart speakers according to claim 1, it is characterised in that: the power amplifier is by the audio-frequency electric of input
Pressure carries out distortionless power amplification.
5. smart speakers according to claim 1, it is characterised in that: the letter/grid current of making an uproar device includes for receiving
First emitter follower of the signal from speaker drive voice coil and receive the of the signal from audio voltage controllable amplifier
Two emitter followers, the second emitter follower are connected with inverting amplifier, and inverting amplifier and the first emitter follower are connect with differential amplifier, poor
Amplifier output noise signal is moved to noise processor.
6. smart speakers according to claim 1, it is characterised in that: the noise processor includes and believes/make an uproar grid
The low-pass filter circuit of device connection is flowed, low-pass filter circuit is connected with amplitude limiter circuit, and amplitude limiter circuit is connected with amplifier integrating circuit,
Amplifier integrating circuit is connect with control voltage amplifier.
7. smart speakers according to claim 1, it is characterised in that: the audio voltage controllable amplifier includes using
In the noise voltage signal received from control voltage amplifier and receive from the preset permission noise electricity of power supply module
The operational amplifier circuit of signal is pressed, operational amplifier circuit is connected with audio voltage amplifier, and audio voltage amplifier is according to operational amplifier circuit gain
Control voltage is adjusted the multiple of audio voltage amplifier.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910726754.8A CN110446146A (en) | 2019-08-07 | 2019-08-07 | Smart speakers |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910726754.8A CN110446146A (en) | 2019-08-07 | 2019-08-07 | Smart speakers |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN110446146A true CN110446146A (en) | 2019-11-12 |
Family
ID=68433771
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910726754.8A Pending CN110446146A (en) | 2019-08-07 | 2019-08-07 | Smart speakers |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110446146A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110876126A (en) * | 2020-01-17 | 2020-03-10 | 四川众兴华业市政照明工程有限公司 | City control management system based on wisdom street lamp |
Citations (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1105788A (en) * | 1993-06-04 | 1995-07-26 | 哈里公司 | Class 'D' audio speaker amplifier circuit with state variable feedback control |
| CN1638266A (en) * | 2003-12-16 | 2005-07-13 | 国际整流器公司 | Volume control in class D amplifier using variable supply voltage |
| JP2007110527A (en) * | 2005-10-14 | 2007-04-26 | Matsushita Electric Works Ltd | Laudspeaker call device |
| CN101030762A (en) * | 2007-01-15 | 2007-09-05 | 四川长虹电器股份有限公司 | Volume controlling method and controller |
| CN201336723Y (en) * | 2008-12-12 | 2009-10-28 | 青岛海信电器股份有限公司 | Audio-output device capable of automatically controlling volume |
| US7869768B1 (en) * | 2006-08-10 | 2011-01-11 | Natan Vishlitzky | Techniques for controlling speaker volume of a portable communications device |
| US20120140917A1 (en) * | 2010-06-04 | 2012-06-07 | Apple Inc. | Active noise cancellation decisions using a degraded reference |
| CN204518035U (en) * | 2015-03-09 | 2015-07-29 | 山东省计算中心（国家超级计算济南中心） | Automatic control of sound volume audio amplifier |
| KR20160086779A (en) * | 2016-06-27 | 2016-07-20 | 이인철 | Bluetooth earphone system that is available to detect the noise of surroundings |
| CN106911980A (en) * | 2017-03-03 | 2017-06-30 | 富士高实业有限公司 | Head circuit with adjustable feedback formula active noise reduction level |
| CN206851015U (en) * | 2017-06-13 | 2018-01-05 | 东南大学 | Can be according to the speaker system of environment automatic regulating volume |
| CN107734427A (en) * | 2017-09-13 | 2018-02-23 | 广州市迪士普信息科技有限公司 | A kind of guard method and device according to voice coil loudspeaker voice coil temperature rise adjust automatically speaker volume |
| CN210579208U (en) * | 2019-08-07 | 2020-05-19 | 常州科先达通讯技术有限公司 | Intelligent loudspeaker |
-
2019
- 2019-08-07 CN CN201910726754.8A patent/CN110446146A/en active Pending
Patent Citations (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1105788A (en) * | 1993-06-04 | 1995-07-26 | 哈里公司 | Class 'D' audio speaker amplifier circuit with state variable feedback control |
| CN1638266A (en) * | 2003-12-16 | 2005-07-13 | 国际整流器公司 | Volume control in class D amplifier using variable supply voltage |
| JP2007110527A (en) * | 2005-10-14 | 2007-04-26 | Matsushita Electric Works Ltd | Laudspeaker call device |
| US7869768B1 (en) * | 2006-08-10 | 2011-01-11 | Natan Vishlitzky | Techniques for controlling speaker volume of a portable communications device |
| CN101030762A (en) * | 2007-01-15 | 2007-09-05 | 四川长虹电器股份有限公司 | Volume controlling method and controller |
| CN201336723Y (en) * | 2008-12-12 | 2009-10-28 | 青岛海信电器股份有限公司 | Audio-output device capable of automatically controlling volume |
| US20120140917A1 (en) * | 2010-06-04 | 2012-06-07 | Apple Inc. | Active noise cancellation decisions using a degraded reference |
| CN204518035U (en) * | 2015-03-09 | 2015-07-29 | 山东省计算中心（国家超级计算济南中心） | Automatic control of sound volume audio amplifier |
| KR20160086779A (en) * | 2016-06-27 | 2016-07-20 | 이인철 | Bluetooth earphone system that is available to detect the noise of surroundings |
| CN106911980A (en) * | 2017-03-03 | 2017-06-30 | 富士高实业有限公司 | Head circuit with adjustable feedback formula active noise reduction level |
| CN206851015U (en) * | 2017-06-13 | 2018-01-05 | 东南大学 | Can be according to the speaker system of environment automatic regulating volume |
| CN107734427A (en) * | 2017-09-13 | 2018-02-23 | 广州市迪士普信息科技有限公司 | A kind of guard method and device according to voice coil loudspeaker voice coil temperature rise adjust automatically speaker volume |
| CN210579208U (en) * | 2019-08-07 | 2020-05-19 | 常州科先达通讯技术有限公司 | Intelligent loudspeaker |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110876126A (en) * | 2020-01-17 | 2020-03-10 | 四川众兴华业市政照明工程有限公司 | City control management system based on wisdom street lamp |
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