CN208174951U - active noise reduction system and earphone - Google Patents
active noise reduction system and earphone Download PDFInfo
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- CN208174951U CN208174951U CN201820801150.6U CN201820801150U CN208174951U CN 208174951 U CN208174951 U CN 208174951U CN 201820801150 U CN201820801150 U CN 201820801150U CN 208174951 U CN208174951 U CN 208174951U
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Abstract
The utility model proposes a kind of active noise reduction system and earphone, which includes：Detection device, the first filter circuit, mode variables circuit, first adder and loudspeaker；The input of first filter circuit and the first output end of detection device connect, and output is connect with first adder first input end；The input of mode variables circuit and the second output terminal of detection device connect, and output is connect with the second input terminal of first adder；Loudspeaker and first adder output connect.The utility model proposes the noise reduction system that a kind of noise reduction mode can be switched, noise reduction system can be realized good noise reduction effect under depth noise reduction mode；The function that enhancing voice is realized while can be realized low frequency noise reduction under speech enhan-cement noise reduction mode is promoted and the extraneous efficiency linked up；And the noise reduction system structure is simple, is easy to Project Realization.
Description
Technical field
The utility model relates to active noise reduction fields, in particular to a kind of active noise reduction system and earphone.
Background technique
Active noise reduction earphone is equal with ambient noise amplitude by secondary sound source sending, and the de-noising sound wave of opposite in phase disappears
Noise waves and noise sound wave sounding are interfered, and realize the elimination of noise.For active noise reduction earphone, anti-acoustic capability is well most basic
Demand in addition to this can't influence noise cancelling headphone user and be exchanged with extraneous, especially with the communication of people.It is main
The de-noising frequency range of dynamic noise cancelling headphone concentrates on middle low-frequency range, the medium-high frequency section that the voice of people is concentrated, and noise cancelling headphone is eliminating noise
While can also eliminate part of speech, due to the part speech absence and cause user to be difficult to not hear from extraneous language
Sound reduces and extraneous ground communication efficiency.
The downlink Dolby circuit and method (application number of patent earphone, earphone；20160353164.1) disclose a kind of earphone
Downlink Dolby circuit and method, can be realized can not hear in the noise circumstance of different frequency range in the speaking of partner
Hold.There is independent voice collecting circuit in the earphone, voice signal is separated from ambient noise signal, side
Just the implementation of subsequent speech enhan-cement.But for the voice signal mixed in ambient noise, Dolby circuit in above-mentioned patent and
Method will be unable to realize the enhancing of voice signal.
Utility model content
To solve the above problems, the utility model proposes a kind of active noise reduction system and earphone, to solve in the prior art
Earphone existing for the technical issues of cannot achieve depth noise reduction and speech enhan-cement.
In a first aspect, the utility model proposes a kind of active noise reduction systems, including：Detection device, the first filter circuit, mould
Formula adjusted circuit, first adder and loudspeaker；The input terminal of first filter circuit and the first of the detection device
Output end connection, the output end of first filter circuit are connect with the first input end of the first adder；The mode
The input terminal of adjusted circuit is connect with the second output terminal of the detection device, the output end of the mode variables circuit with it is described
Second input terminal of first adder connects；The loudspeaker is connect with the output end of the first adder；The detection dress
The voice signal for detecting sound is set, the sound includes ambient noise and voice；First filter circuit is for eliminating
Low-frequency noise；The mode variables circuit is used to the active noise reduction system being adjusted to pattern of speech enhancement or depth noise reduction mould
Formula；The first adder is for the output of first filter circuit to be added with the output of the mode variables circuit；Institute
Loudspeaker is stated for noise cancellation signal to be converted de-noising sound wave.
Further, the detection device includes feedforward microphone and feedback microphones；The output of the feedforward microphone
End is connect with the input terminal of the mode variables circuit；The output end of the feedback microphones is defeated with first filter circuit
Enter end connection.
Further, the mode variables circuit includes second filter circuit, third filter circuit, mode selection circuit
And second adder；The second output terminal of detection device described in the first input end of second filter circuit connects, described
Second input terminal of the second filter circuit is connect with the first output end of the mode selection circuit, second filter circuit
Output end is connect with the first input end of the second adder；
The first input end of the third filter circuit is connect with the second output terminal of the detection device, the third filter
Second input terminal of wave circuit is connect with the second output terminal of the mode selection circuit, the output end of the third filter circuit
It is connect with the second input terminal of the second adder；The second of the output end of the second adder and the first adder
Input terminal connection；Second filter circuit is for eliminating high-frequency noises；The third filter circuit is for realizing voice increasing
Strong function；The mode selection circuit is for determining mode locating for presently described active noise reduction system；Second addition
Device is for the output of second filter circuit to be added with the output of the third filter circuit.
Further, first filter circuit include sequentially connected analog to digital conversion circuit one, feedback filtering circuit and
Digital-to-analogue conversion circuit one.
Further, second filter circuit include sequentially connected analog to digital conversion circuit two, feedforward filter circuit and
D/A converting circuit two.
Further, the third filter circuit include sequentially connected analog to digital conversion circuit three, speech enhancement circuit and
D/A converting circuit three.
Second aspect, the utility model proposes a kind of noise cancelling headphones, drop including active described in first aspect any one
It makes an uproar system.
Further, the active noise reduction system further includes mode selection circuit, and the earphone further includes that model selection is opened
It closes, the mode selection switch is connect with the mode selection circuit, for determining the operating mode of the earphone.
The utility model proposes a kind of active noise reduction system and earphone, which includes：Detection device, the first filtered electrical
Road, mode variables circuit, first adder and loudspeaker；The input of first filter circuit and the first output end of detection device
Connection, output are connect with first adder first input end；The input of mode variables circuit and the second output terminal of detection device
Connection, output are connect with the second input terminal of first adder；Loudspeaker and first adder output connect.It can by increasing mode
The noise reduction of earphone is divided into depth noise reduction mode and with the noise reduction mode of voice enhanced function by power transformation road.With prior art phase
Than the utility model proposes the noise reduction systems that a kind of noise reduction mode can be switched, and noise reduction system can be real under depth noise reduction mode
Existing good noise reduction effect；The function of enhancing voice is realized while can be realized low frequency noise reduction under speech enhan-cement noise reduction mode
Can, it is promoted and the extraneous efficiency linked up；And the noise reduction system structure is simple, is easy to Project Realization.
Detailed description of the invention
It, below will be right in order to illustrate more clearly of specific embodiment of the present invention or technical solution in the prior art
Specific embodiment or attached drawing needed to be used in the description of the prior art are briefly described, it should be apparent that, it is described below
In attached drawing be that some embodiments of the utility model are not paying creativeness for those of ordinary skill in the art
Under the premise of labour, it is also possible to obtain other drawings based on these drawings.
Fig. 1 shows a kind of structural schematic diagram of the active noise reduction system provided in the utility model embodiment 1；
Fig. 2 shows the structural schematic diagrams of the mode variables circuit provided in the utility model embodiment 1；
Fig. 3 has gone out two kinds of noise reduction mode schematic diagrames of the earphone provided in the utility model embodiment 2；
Specific embodiment
It is practical new to this below in conjunction with attached drawing to keep the purpose of this utility model, technical solution and advantage clearer
The technical solution of type carries out clear, complete description.Obviously, described embodiment is only that a part of the utility model is implemented
Example, instead of all the embodiments.Based on the embodiments of the present invention, those of ordinary skill in the art are not making wound
Every other embodiment obtained under the premise of the property made labour, fall within the protection scope of the utility model.
In the description of the present invention, it should be noted that term " first ", " second " and " third " are only used for describing
Purpose is not understood to indicate or imply relative importance.Unless otherwise clearly defined and limited, term " connection ", " phase
It even " shall be understood in a broad sense, for example, it may be being fixedly connected, may be a detachable connection, or be integrally connected；It can be machine
Tool connection, is also possible to be electrically connected；It can be directly connected, two members can also be can be indirectly connected through an intermediary
Connection inside part.For the ordinary skill in the art, it can understand that above-mentioned term is practical new at this with concrete condition
Concrete meaning in type.
Embodiment 1
Active noise reduction system structural schematic diagram as shown in Figure 1, the utility model proposes a kind of active noise reduction system 10,
Including detection device 100, the first filter circuit 200, mode variables circuit 300, first adder 400 and loudspeaker 500.
Detection device 100 includes the first output end a1 and second output terminal a2.
First adder 400 includes first input end b1, the second input terminal b2 and output end b3.
The input terminal of first filter circuit 200 is connect with the first output end a1 of detection device 100, the first filter circuit
200 output end is connect with the first input end b1 of the first adder 400.
The input terminal of mode variables circuit 300 is connect with the second output terminal a2 of detection device 100, mode variables circuit
300 output end is connect with the second input terminal b2 of first adder 400.
Loudspeaker 500 is connect with the output end b3 of first adder 400.
Detection device 100 is used to detect the voice signal of sound, wherein the sound includes ambient noise and voice.Inspection
Surveying device 100 can be detected pure ambient noise or the ambient noise comprising voice.
First filter circuit 200 is for eliminating low-frequency noise.To eliminate low-frequency noise, first filter 310 is generallyd use
Filter based on feedback topology structure.
Mode variables circuit 300 is used to active noise reduction system 10 being adjusted to pattern of speech enhancement or depth noise reduction mode.
Pattern of speech enhancement is to enhance voice signal for frequency range where voice；Depth noise reduction mode is making an uproar for frequency range where voice
Sound carries out noise reduction.Both of which can free switching.
First adder 400 is for the output of the first filter circuit 200 to be added with the output of mode variables circuit 300.
The superposition of the realization two parts of signals of first adder 400.
Loudspeaker 500 is used to noise cancellation signal converting de-noising sound wave.By depth de-noising electric signal, (depth drops loudspeaker 500
Make an uproar under mode) or de-noising electric signal (under pattern of speech enhancement) with voice enhanced function be converted into acoustical signal.
In one embodiment, detection device 100 include feedforward microphone and feedback microphones, feedforward microphone it is defeated
Outlet is connect with the input terminal of mode variables circuit 300, and feedback microphones are connect with the input terminal of the first filter circuit 200.Before
The acoustical signal that feedback microphone will test is transmitted to mode variables circuit 300 after being converted to electric signal；Feedback microphones will test
To acoustical signal be converted to after electric signal and be transmitted to the first filter circuit 200.
In one embodiment, mode variables electrical block diagram as shown in Figure 2, the mode variables circuit
300 include second filter circuit 310, third filter circuit 330, mode selection circuit 320 and second adder 340.
Second filter circuit 310 includes first input end d1, the second input terminal d2 and output end d3.
Third filter circuit 330 includes first input end e1, the second input terminal e2 and output end e3.
Mode selection circuit 320 includes the first Ausgang 1 and the second defeated Ausgang 2.
Second adder 340 includes first input end h1, the second input terminal h2 and output end h3.
The first input end d1 of second filter circuit 310 is connect with the second output terminal a2 of detection device 100, the second filtering
Second input terminal d2 of circuit 310 is connect with the first Ausgang 1 of mode selection circuit 320, the second filter circuit 310 it is defeated
Outlet d3 is connect with the first input end h1 of second adder 340.
The first input end e1 of third filter circuit 330 is connect with the second output terminal a2 of detection device 100, third filtering
Second input terminal e2 of circuit 330 is connect with the second output terminal f2 of mode selection circuit 320, third filter circuit 330 it is defeated
Outlet e3 is connect with the second input terminal h2 of second adder 340.
The output end h3 of second adder 340 is connect with the second input terminal b2 of first adder 400.
Second filter circuit 310 is for eliminating high-frequency noises.To eliminate high-frequency noises, the second filter circuit 310 is logical
Frequently with the filter based on feed forward topology.
Third filter circuit 330 for realizing speech enhan-cement function.Third filter circuit 330 is in where voice
High band enhances voice signal.
Mode selection circuit 320 is for determining mode locating for current active noise reduction system 10.When in depth noise reduction mould
When formula, the second filter circuit 310 is power-up state, and third filter circuit 330 does not work；When being in Speech enhancement mode, the
Three filter circuits 330 are power-up state, and the second filter circuit 310 does not work.
Second adder 340 is for the output of the second filter circuit 310 to be added with the output of third filter circuit 330.
The output of two kinds of filter circuits can be combined by second adder 340, realize corresponding comprehensive Noise Reduction function.
Above-mentioned active noise reduction system 10 utilizes mode variables circuit 300, on the basis of original decrease of noise functions, according to whether
Demand with enhancing voice realizes depth decrease of noise functions and the decrease of noise functions with speech enhan-cement effect respectively.Increase with voice
The difference of powerful noise reduction system and the noise reduction system with depth decrease of noise functions is：Filtering with voice enhanced function
The filter circuit for being originally used for medium-high frequency noise reduction is substituted in circuit, i.e., realizes medium-high frequency by losing the noise reduction effect of medium-high frequency
Voice enhanced function, realize well balanced between decrease of noise functions and voice enhanced function.
In one embodiment, the first filter circuit 200 includes sequentially connected analog to digital conversion circuit one, feedback filtering
Circuit and digital-to-analogue conversion circuit one.The analog acoustic signal of analog to digital conversion circuit self-test device in one future 100 is converted into digital letter
It is transmitted to feedback filtering circuit after number, digital noise cancellation signal one, the number noise cancellation signal are exported after feedback filtering processing of circuit
One exports after D/A converting circuit one is converted into simulation noise cancellation signal one to first adder 400.
In one embodiment, the second filter circuit 310 includes sequentially connected analog to digital conversion circuit two, feedforward filtering
Circuit and D/A converting circuit two.The analog acoustic signal of analog to digital conversion circuit self-test device in two future 100 is converted into digital letter
It is transmitted to feedforward filter circuit after number, exports digital noise cancellation signal two, the number noise cancellation signal after feedforward filter circuit processing
Two export after D/A converting circuit two is converted into simulation noise cancellation signal two to second adder 340.
In one embodiment, third filter circuit 330 further includes sequentially connected analog to digital conversion circuit three, voice increasing
Forceful electric power road and D/A converting circuit three.The analog acoustic signal of analog to digital conversion circuit self-test device in three future 100 is converted into number
Speech enhancement circuit is transmitted to after signal, digital speech is exported after speech enhancement circuit is handled enhances signal, the digital speech
Enhancing signal exports after D/A converting circuit three is converted into analog voice enhancing signal to second adder 340.
Embodiment 2
The utility model proposes a kind of earphones, including the active noise reduction system 10 proposed in embodiment 1.
In one embodiment, the noise reduction mode structural schematic diagram of earphone as shown in Figure 3, above-mentioned earphone further include mould
Formula selection circuit and mode selection switch, mode selection switch connect the Working mould for determining earphone with mode selection circuit
Formula.Preferably, it can be set as default mode with depth noise reduction mode 1, if being not turned on above-mentioned model selection quick closing valve, the earphone one
It directly operates in depth noise reduction mode, i.e. the feed forward noise reduction noise reduction mode that adds feedback noise reduction；If opening above-mentioned mode selection switch,
Then the earphone closes depth noise reduction mode 1, the noise reduction mode that beginning pattern of speech enhancement 2, i.e. feedback noise reduction add Speech enhancement.
In one embodiment, above-mentioned earphone further includes feedforward microphone and feedback microphones.Feedforward microphone is used for
Close to the voice signal of noise source inside test earphone, which is generally positioned at earphone back cavity；Feedback microphones are for examining
The voice signal inside earphone by ear is surveyed, which is generally positioned at earphone ante-chamber.
Compared with prior art, the utility model proposes the noise reduction systems that a kind of noise reduction mode can be switched, by the noise reduction system
System is applied to earphone, can be realized good noise reduction effect under depth noise reduction mode；It can under speech enhan-cement noise reduction mode
The function that enhancing voice is realized while realizing low frequency noise reduction is promoted and the extraneous efficiency linked up；And the noise reduction system structure letter
List is easy to Project Realization.
The technical effect and preceding method of device provided by the utility model embodiment, realization principle and generation are implemented
Example is identical, and to briefly describe, Installation practice part does not refer to place, can refer to corresponding contents in preceding method embodiment.
In all examples being illustrated and described herein, any occurrence should be construed as merely illustratively, without
It is as limitation, therefore, other examples of exemplary embodiment can have different values.
It should be noted that：Similar label and letter indicate similar terms in following attached drawing, therefore, once a certain Xiang Yi
It is defined in a attached drawing, does not then need that it is further defined and explained in subsequent attached drawing.
Block diagram in attached drawing shows that the system of multiple embodiments according to the present utility model, method and computer program produce
The architecture, function and operation in the cards of product.In this regard, each box in block diagram can represent a module,
A part of program segment or code, a part of the module, section or code include one or more for realizing regulation
Logic function executable instruction.It should also be noted that in some implementations as replacements, function marked in the box
It can occur in a different order than that indicated in the drawings.For example, two continuous boxes can actually be held substantially in parallel
Row, they can also be executed in the opposite order sometimes, and this depends on the function involved.It is also noted that in block diagram
The combination of box in each box and block diagram, can function or movement as defined in executing it is dedicated hardware based
System is realized, or can be realized using a combination of dedicated hardware and computer instructions.
Claims (8)
1. a kind of active noise reduction system, which is characterized in that including：Detection device, the first filter circuit, mode variables circuit,
One adder and loudspeaker；
The input terminal of first filter circuit is connect with the first output end of the detection device, first filter circuit
Output end is connect with the first input end of the first adder；
The input terminal of the mode variables circuit is connect with the second output terminal of the detection device, the mode variables circuit
Output end is connect with the second input terminal of the first adder；
The loudspeaker is connect with the output end of the first adder；
The detection device is used to detect the voice signal of sound, and the sound includes ambient noise and voice；
First filter circuit is for eliminating low-frequency noise；
The mode variables circuit is used to the active noise reduction system being adjusted to pattern of speech enhancement or depth noise reduction mode；
The first adder is for the output of first filter circuit to be added with the output of the mode variables circuit；
The loudspeaker is used to noise cancellation signal converting de-noising sound wave.
2. active noise reduction system according to claim 1, which is characterized in that the detection device include feedforward microphone and
Feedback microphones；
The output end of the feedforward microphone is connect with the input terminal of the mode variables circuit；
The output end of the feedback microphones is connect with the input terminal of first filter circuit.
3. active noise reduction system according to claim 1, which is characterized in that the mode variables circuit includes the second filtering
Circuit, third filter circuit, mode selection circuit and second adder；
The first input end of second filter circuit is connect with the second output terminal of the detection device, second filtered electrical
Second input terminal on road is connect with the first output end of the mode selection circuit, the output end of second filter circuit and institute
State the first input end connection of second adder；
The first input end of the third filter circuit is connect with the second output terminal of the detection device, the third filtered electrical
Second input terminal on road is connect with the second output terminal of the mode selection circuit, the output end of the third filter circuit and institute
State the second input terminal connection of second adder；
The output end of the second adder is connect with the second input terminal of the first adder；
Second filter circuit is for eliminating high-frequency noises；
The third filter circuit for realizing speech enhan-cement function；
The mode selection circuit is for determining mode locating for presently described active noise reduction system；
The second adder is for the output of second filter circuit to be added with the output of the third filter circuit.
4. active noise reduction system according to claim 1, which is characterized in that first filter circuit includes being sequentially connected
Analog to digital conversion circuit one, feedback filtering circuit and digital-to-analogue conversion circuit one.
5. active noise reduction system according to claim 3, which is characterized in that second filter circuit includes being sequentially connected
Analog to digital conversion circuit two, feedforward filter circuit and D/A converting circuit two.
6. active noise reduction system according to claim 3, which is characterized in that the third filter circuit includes being sequentially connected
Analog to digital conversion circuit three, speech enhancement circuit and D/A converting circuit three.
7. a kind of earphone, which is characterized in that including the active noise reduction system as described in claim 1 to 6 any one.
8. earphone according to claim 7, which is characterized in that the active noise reduction system further includes mode selection circuit,
The earphone further includes mode selection switch, and the mode selection switch is connect with the mode selection circuit, for determining
State the operating mode of earphone.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201820801150.6U CN208174951U (en) | 2018-05-25 | 2018-05-25 | active noise reduction system and earphone |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201820801150.6U CN208174951U (en) | 2018-05-25 | 2018-05-25 | active noise reduction system and earphone |
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| CN208174951U true CN208174951U (en) | 2018-11-30 |
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| CN201820801150.6U Expired - Fee Related CN208174951U (en) | 2018-05-25 | 2018-05-25 | active noise reduction system and earphone |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108810692A (en) * | 2018-05-25 | 2018-11-13 | 会听声学科技（北京）有限公司 | Active noise reduction system, active denoising method and earphone |
| CN110087159A (en) * | 2019-04-03 | 2019-08-02 | 歌尔科技有限公司 | A kind of feedback noise reduction method, system and earphone |
| CN110972007A (en) * | 2019-10-30 | 2020-04-07 | 上海集研机电科技有限公司 | Active earphone noise reduction method suitable for ship high-noise scene |
-
2018
- 2018-05-25 CN CN201820801150.6U patent/CN208174951U/en not_active Expired - Fee Related
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108810692A (en) * | 2018-05-25 | 2018-11-13 | 会听声学科技（北京）有限公司 | Active noise reduction system, active denoising method and earphone |
| CN110087159A (en) * | 2019-04-03 | 2019-08-02 | 歌尔科技有限公司 | A kind of feedback noise reduction method, system and earphone |
| CN110087159B (en) * | 2019-04-03 | 2020-11-17 | 歌尔科技有限公司 | Feedback noise reduction method, system, earphone and storage medium |
| CN110972007A (en) * | 2019-10-30 | 2020-04-07 | 上海集研机电科技有限公司 | Active earphone noise reduction method suitable for ship high-noise scene |
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