CN105025419B - A kind of active noise reduction system and method - Google Patents
A kind of active noise reduction system and method Download PDFInfo
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- CN105025419B CN105025419B CN201410181467.0A CN201410181467A CN105025419B CN 105025419 B CN105025419 B CN 105025419B CN 201410181467 A CN201410181467 A CN 201410181467A CN 105025419 B CN105025419 B CN 105025419B
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Abstract
The present invention provides a kind of active noise reduction system and method, the system and included：Digital signal panel, collection of simulant signal and output board, the power module laid positioned at cuboid interior parallel；Input interface 6, output interface 7, signal ground interface 9, shell are set on the left side of the cuboid interface 10, attaching plug 13, power safety 12 and power switch 11；The collection of simulant signal includes two-way simulation AD and two-way simulation DA with output board, and it is connected with the input interface 6 of active noise reduction system and output interface 7, the input interface 6 is used to input from analog electrical signal caused by sound transducer, and the output interface is used for noise reduction analog signal caused by external electronic device output active noise reduction system；The digital signal panel with collection of simulant signal is parallel with output board lays, and the both ends of two planks are connected by two connectors；And the digital signal processing module, for the feature of Analyze noise signal, noise signal is divided into Main Noise Sources and secondary noise source.
Description
Technical field
The present invention relates to noise reduction field, and in particular to a kind of an active noise reduction system and method.
Background technology
Work, life area in reality, common various noises, these noises are often to the physical and mental health of surrounding people
Cause various injuries, or even the production work for influenceing, destorying the scene.Therefore, in order to reach the purpose of noise reduction, usually using actively
Two methods of noise reduction and passive noise reduction, and active noise reduction function be exactly produced by noise reduction system it is equal with outside noise reverse
Sound wave, noise is neutralized, so as to realize the effect of noise reduction.
Active noise control is a kind of active noise control technique based on sound wave coherent superposition principle, earliest by P.Lueg
Itd is proposed in its patent US2043416, its general principle is that secondary sound source is introduced in sound field and is sent using it with initially making an uproar
Sound amplitude is identical but opposite in phase " antinoise ", initial noisc is obtained relevant counteracting, so as to reach the purpose of noise suppressed.
Compared with traditional passive noise-reduction method, Technique of Active Noise Control main advantage is to obtain preferably with smaller volume
Low frequency noise reduction.As the improvement of people's living standards, low-frequency noise pollution problem is increasingly notable, Technique of Active Noise Control
Practical demand is increasingly urgent.On the other hand, by the development of last 100 yearses, especially with recent decades Digital Signal Processing
The leap of technology, Technique of Active Noise Control is increasingly mature, and its practicalization is just progressively accelerated.
In order to reach good active noise reduction effect, an outstanding active control system is whole active noise reduction platform
Basis.The active control system of early stage primarily focuses on the noise and vibration information for gathering multiple measurement points, feedback noise reduction system
Separated with acquisition system, the substantial amounts of point sensor that gathers needs to be connected with collecting device by longer analog signal line, both increases
Unnecessary wiring difficulty has been added to reduce the reliability of equipment again, and the separately positioned of reponse system further increases whole active
Noise reduction system arranges the difficulty with implementing so that whole system seems scattered, poorly efficient and unreliable.And make a general survey of active noise reduction skill
The commonly used place of art, generally has that site surrounding is complicated, the long line installation difficulty in monitoring point, Noise Reduction point and monitoring point away from
From it is nearer the features such as, so one has collection input and control output, compact, miniaturization, low-power consumption, is easy to multiple spot group simultaneously
The needs that the active control system of net becomes a reality.
The content of the invention
Inputted it is an object of the present invention to provide a kind of small size, low-power consumption, collection and be output in one with control, had
The audio active controller of networking function, and in particular to a kind of active noise reduction system and method.
To achieve these goals, the present invention provides a kind of active noise reduction system, the active noise reduction system be comprising：Position
Digital signal panel, collection of simulant signal and output board, some power modules laid in cuboid interior parallel；The length
Input interface 6, output interface 7, signal ground interface 9, shell are set on the left side of cube interface 10, attaching plug 13, power supply
Insurance 12 and power switch 11；
The collection of simulant signal and output board include two-way simulation AD and two-way simulation DA, and with active noise reduction system
Input interface 6 and output interface 7 connect, and the input interface 6 is used to input from analog electrical signal caused by sound transducer, institute
Output interface is stated to be used for noise reduction analog signal caused by external electronic device output active noise reduction system；
The digital signal panel with collection of simulant signal is parallel with output board lays, and the both ends of two planks pass through
Two contact pins are connected, and are connected by another contact pin with network communication interface；And the digital signal processing module, it is used for
The feature of Analyze noise signal, noise signal is divided into Main Noise Sources and secondary noise source；The collection of simulant signal with
Output board is used to carry out digital-to-analogue conversion processing to the acoustical signal of collection, produces data signal；
Wherein, the digital signal panel (5) includes：Digital filter block and signal compensation processing module；
The digital filter block includes some digital filters, and parallel processing multichannel is not simultaneously for all digital filters
With the signal of frequency band, and then retain the signal in frequency band, the signal outside attenuation band, ensure that the frequency response of whole passband is steady；
The signal compensation processing module, for the analog signal collected to be carried out into analog to digital conversion, then become based on modulus
The data signal got in return obtains the strength information of signal, and finally the relation of signal Analysis numerical value and time obtain signal phase again
Information；By carrying out the contrast of intensity and phase to signal caused by multi-channel filter, and then obtain the analysis of primary and secondary noise
As a result；Reverse superposed signal is finally produced according to main noise signal, reverse superposed signal is used to produce by D/A modular converters
Inverse analog electric signal, transducer of the inverse analog electric signal outside driving produce reverse air acoustical signal or reverse
Mechanical oscillation signal, these reverse signals are added on main noise signal, reach the purpose of noise reduction.
The equipment such as above-mentioned modules, interface are arranged in a cuboid, and the upper surface of the cuboid is radiating
Shell 3, and the heat-dissipating casing 3 is placed in parallel with the collection of simulant signal with output board, and the left side of heat-dissipating casing 3 is set up separately
A projection is put, the projection is pure aluminum material, and the projection is in contact with the collection of simulant signal with output board upper surface,
And then play by the heat of casing internal be transmitted to can be outside effect；
Some power modules are placed on the cuboid lower surface；
The signal ground interface 9 and shell interface 10 be respectively used to equipment room signal and be grounded altogether with housing shroud；
Attaching plug 13 connects external power source.
Optionally, power safety 12 and power switch 11 are also set up on the left side of above-mentioned cuboid；
The power safety 12 is used for the overcurrent protection of external power source；The power switch 11 controls active noise reduction system
Switch.
Optionally, embedded system and fpga chip of the above-mentioned digital signal panel based on OMAPL137, and the plate is set
There are two standard serial ports and a 10M/100M network interface.
Optionally, above-mentioned collection of simulant signal includes with output board 4：
Two 16bit and sample rate 4M/s AD input channels；
Two 16bit DA output channels；
And input interface 6 can be arranged as required into control source or electric current input pattern.
Optionally, the digital signal panel 5 is respectively 120 pins by two with output board 4 with collection of simulant signal
PC104 connectors connection, and by 8 connection copper posts be fixed on 3 on heat-dissipating casing.
In addition, present invention also offers a kind of active denoising method, methods described includes：
Step 101) sonic transducer gathers acoustical signal or vibration signal, and the acoustical signal of collection is converted into electric signal；
The electric signal of conversion is carried out Digital Signal Processing by step 102), by the analysis to data signal, including is passed through
Digital filtering obtains the spectrum distribution of signal, analyzes to obtain the intensity distribution of signal by the size of numerical value, and then according to frequency
Main Noise Sources and secondary noise source are separated with intensity region, then the feature of main noise signal, produced by digital to analog conversion module
A raw reverse superposed simulation signal, the superposed signal frequency is identical with noise signal, and opposite in phase, intensity is equal, carries out anti-
To noise reduction；
Wherein, the feature of main noise includes：The frequency and intensity of signal.
Optionally, above-mentioned steps 101) also include before：
Noise signal is filtered in different frequency bands by some railway digital wave filters, therefrom analysis draws the strong of signal
The phase place change information of degree and signal；
The signal intensity drawn and phase place change information are subjected to unified contrast, and then obtain noise in all noise signals
Maximum signal is acted on, while records the data of all noise signals and carries out probability statistics, and then judges following a period of time
Probability interior, that each noise signal occurs；
Using above-mentioned statistical information, noise reduction process is carried out to caused noise.Compared with prior art, technology of the invention
Advantage is：Accurate positioning analysis, the signal of different frequency bands independent can be handled, eliminate the dry of irrelevant information
Disturb, the whole process of signal is recorded, realizes probability statistical analysis, it is pre- to judge, pretreatment, it has been completely free of passive processing
Deficiency.
Brief description of the drawings
Fig. 1-a and 1-b are audio active controller cut-away view provided in an embodiment of the present invention and panel figure；
Fig. 2 audio active controller overall appearance figures provided in an embodiment of the present invention.
Accompanying drawing identifies：
1st, AC/DC power supplys, 2, DC/DC power supplys, 3, case body,
4th, collection of simulant signal and output board, 5, digital signal panel, 6, collection input interface,
7th, output interface is controlled, 8, network interface, 9, signal ground binding post,
10th, shell ground binding post, 11, power switch, 12, power safety,
13rd, attaching plug.
Embodiment
The present invention is further described with reference to the accompanying drawings and examples.
The present invention provides a kind of audio active controller, including：By digital signal processing module 5 and collection of simulant signal mould
Block 4；Wherein collection of simulant signal module 4 includes two-way simulation AD and two-way simulation DA, and connects with input interface 6, output interface 7
Connect；Digital signal processing module 5 is connected with collection of simulant signal module 4, and is connected with network communication interface 8；The He of power module 1
2 are fixed on heat-dissipating casing 3；Signal ground interface 9 and shell interface 10 be respectively used to equipment room signal altogether and housing shroud
Ground connection；Attaching plug 13 connects external power source；Power safety 12 is used for the overcurrent protection of external power source；The control of power switch 11 system
The switch of system.
Above-mentioned digital signal processing module includes the embedded system one using OMAPL137 as core, and is integrated with one
FPGA (EP3CF484), and with two standard serial ports, a 10M/100M network interface；Collection of simulant signal module includes two
16bit, sample rate 4M/s AD input channels, two 16bit DA output channels, meanwhile, in order to meet input signal source
Different type, input can be arranged as required into control source or electric current input pattern；This number of audio active controller
The mode that type families are united and simulation system is integrated together can reduce the cost of whole system, while more convenient scene is quickly established
Measurement architecture.
Above-mentioned analog signal AD collection and DA output boards 4 include two-way simulation input and two-way simulation output, and with input
Interface 6, output interface 7 connect, it is this will input the modes that are integrated together of AD and output DA avoid traditional input with it is defeated
Go out cost increase caused by making sheet respectively, reliability reduces, equipment volume is big and the various disadvantages such as power consumption increase, and can be with
Meets the needs of practical application.
Above-mentioned digital signal processing module 5 is connected with collection of simulant signal module 4, and is connected with network communication interface 8, this
The method that network function is integrated into active control electronic system by kind can realize that multiple active control electronic systems pass through network
Networked, and then realize multiple spot, remote control.
Optionally, said system also includes power module 1 and 2, and heat-dissipating casing；And power module 1 and 2 is fixed on radiating
On shell 3, heat caused by power supply effectively can be transmitted to outside by this method by equipment metal shell.
The present invention innovation be in, from generally use to signal carry out analogy method processing it is different, at digitlization
Manage noise signal, can accurate Analyze noise signal feature, distinguish Main Noise Sources and secondary noise source, can basis
The needs of user, handled for some special noise signal, due to the distinctive advantage of Digital Signal Processing, you can real
Existing signal procesing in time domain can realize that frequency-region signal is handled again, and conventional simulation process method is unable to reach such property at all
Energy., can be according to the analysis result of existing Noise Acquisition data, to that will send out meanwhile the present invention also has ability of self-teaching
Raw noise signal is predicted, and adjusts noise reduction predeterminated target in time, has obvious noise reduction to random noise, these
All it is that conventional noise reduction sets the function that can not have.Noise signal is carried out in different frequency bands by multi-path digital wave filter
Filtering, therefrom analyzes the intensity of signal, the phase place change of signal, these data is carried out to unified contrast, and then judge
The effect of those signals is maximum, while records the data of all signals, and carries out probability statistical analysis, and then judges future one
In the section time, the probability of each signal appearance, so that user makes preparation in advance, reach the effect guarded against in advance.
Embodiment
According to the audio active controller cut-away view developed of the present invention with panel figure as shown in Fig. 1-a and 1-b, outside it
See as shown in Figure 2.Active control electronic system is integrally rectangle body, and shell sizes are：Long 200mm, wide 104mm are high
100mm。
Audio active controller is mainly made up of outside mechanical hull and internal electron board two large divisions, wherein outside
Mechanical hull includes housing 3 and connector and control panel, collection input interface 6, feedback output interface 7, network interface 8, letter
Number earth terminal 9 and chassis ground binding post 10, power switch 11, power safety 12 and attaching plug 13 all concentrate arrangement
In on panel.
It can be fixedly mounted during in-site installation by four mounting holes of outer casing bottom, can also be directly placed at stable table top
On.Collection input interface 6 is 4 pin aviation plugs with feedback output interface 7, and network interface 8 is 10 pin aviation plugs, attaching plug
13 be 3 pin aviation plugs, and power safety 12 is column protective tube, and signal ground binding post 9 and chassis ground binding post 10 are spiral shell
Bolt copper post, power switch 11 switch for circular key.
System work when first by external sensor be connected to collection input interface 6 (if constant-current source output transducer,
Then need collection input interface 6 being arranged to Constant current input end by jumper cap), control output interface 7 is connected to circumferential work
The input of rate amplifier, network interface 8 are connected on standard ethernet interchanger, can be as desired by network exchange data
With control instruction, in the place that electromagnetic interference is complicated, should by shell by the earth of chassis ground binding post 10, with other equipment
, should be by signal ground binding post 9 altogether when connection needs signal altogether, attaching plug 13 connects AC220/50Hz alternating currents.On
After stating interface connection correctly as needed, startup power supply switch 11 makes active control electronic system start working.
Audio active controller excellent performance, pass through test, input background noise Vpp<100uV, output background noise Vpp
<100uV, obvious crosstalk is not measured between input channel, obvious crosstalk, equipment power dissipation are not measured between output channel<7.3W, A/D are adopted
Sample significance bit is 13, highest sample rate 4M/s, output harmonic wave distortion THD<0.1%, maximum detection amount input voltage Vpp
(max)=5V, maximum output voltage Vpp (max)=10V, Simulation scale-up adjustable magnification is inputted.
Present invention also offers a kind of active denoising method, methods described includes：
Step 101) sonic transducer gathers acoustical signal or vibration signal, and the acoustical signal of collection is converted into electric signal；
The electric signal of conversion is carried out Digital Signal Processing by step 102), by the analysis to data signal, including is passed through
Digital filtering obtains the spectrum distribution of signal, analyzes to obtain the intensity distribution of signal by the size of numerical value, and then according to frequency
Main Noise Sources and secondary noise source are separated with intensity region, then the feature of main noise signal, produced by digital to analog conversion module
A raw reverse superposed simulation signal, the superposed signal frequency is identical with noise signal, and opposite in phase, intensity is equal, carries out anti-
To noise reduction；
Wherein, the feature of main noise includes：The frequency and intensity of signal.
Above-mentioned steps 101) also include before：
Noise signal is filtered in different frequency bands by some railway digital wave filters, therefrom analysis draws the strong of signal
The phase place change information of degree and signal；The signal intensity drawn and phase place change information are subjected to unified contrast, and then obtain institute
There is the signal that noise contributions are maximum in noise signal, while record the data of all noise signals and carry out probability statistics, and then
Judge in following a period of time, the probability that each noise signal occurs；Using above-mentioned statistical information, caused noise is dropped
Make an uproar processing.
In summary, the present invention provides a kind of audio active controller, and its purposes is by gathering acoustical signal or shaking
Dynamic signal, exports corresponding analog control signal after carrying out Digital Signal Processing, is finally reached the purpose of vibration and noise reducing.Whole electricity
It is subsystem small volume, low in energy consumption, reliable and stable.The system includes：It is made up of digital signal panel 5 and analog signal plate 4
The system core；Wherein analog signal plate 4 include two-way simulation AD (constant hydraulic source and constant-current source) with two-way simulation DA, and with it is defeated
Incoming interface 6, output interface 7 connect；Digital signal panel 5 is connected with collection of simulant signal with output board 4, and and network service
Interface 8 connects；Power module 1 and 2 is fixed on heat-dissipating casing 3；Interface 10 is respectively used to equipment to signal ground interface 9 with shell
Between signal altogether with housing shroud be grounded；Attaching plug 13 connects external power source；Power safety 12 is used for the excessively stream of external power source
Protection；The switch of the control system of power switch 11.
In addition to the implementation, all technical schemes formed using equivalent substitution or equivalent transformation, all falling within the present invention will
In the protection domain asked.
Claims (7)
1. a kind of active noise reduction system, it is characterised in that the active noise reduction system includes：Laid positioned at cuboid interior parallel
Digital signal panel (5), collection of simulant signal and output board (4), some power modules；Set on the left side of the cuboid
With putting input interface (6), output interface (7), signal ground interface (9), shell interface (10), attaching plug (13), power safety
And power switch (11) (12)；
The collection of simulant signal and output board include two-way simulation AD and two-way simulation DA, and with the input of active noise reduction system
Interface (6) and output interface (7) connection, the input interface (6) are used to input from analog electrical signal caused by sound transducer,
The output interface is used for noise reduction analog signal caused by external electronic device output active noise reduction system；The analog signal
Collection is used to carry out digital-to-analogue conversion processing to the acoustical signal of collection with output board, produces data signal；
The digital signal panel (5) with collection of simulant signal is parallel with output board lays, and the both ends of two planks pass through
Contact pin is connected, and is connected by another contact pin with network communication interface；And the digital signal processing module, for analyzing
The feature of noise signal, noise signal is divided into Main Noise Sources and secondary noise source；
Wherein, the digital signal panel (5) includes：Digital filter block and signal compensation processing module；
The digital filter block includes some digital filters, and parallel processing multichannel is different frequently simultaneously for all digital filters
The signal of band, and then retain the signal in frequency band, the signal outside attenuation band, ensure that the frequency response of whole passband is steady；
The signal compensation processing module, for the analog signal collected to be carried out into analog to digital conversion, then obtained based on analog to digital conversion
The data signal arrived obtains the strength information of signal, and finally the relation of signal Analysis numerical value and time obtain the letter of signal phase again
Breath；By carrying out the contrast of intensity and phase to signal caused by multi-channel filter, and then obtain the analysis knot of primary and secondary noise
Fruit；Reverse superposed signal is finally produced according to main noise signal.
2. active noise reduction system according to claim 1, it is characterised in that the modules of described active noise reduction system
It is laid on unit in a cuboid；
The upper surface of the cuboid is heat-dissipating casing (3), and the heat-dissipating casing (3) and the collection of simulant signal and output board
It is placed in parallel, and heat-dissipating casing (3) left-half sets a projection, the projection is pure aluminum material, and the projection and institute
Collection of simulant signal is stated to be in contact with output board upper surface, so play by the heat of casing internal be transmitted to can be outside work
With；
Some power modules are placed on the cuboid lower surface；
The signal ground interface (9) and shell interface (10) be respectively used to equipment room signal and be grounded altogether with housing shroud；
Attaching plug 13 connects external power source.
3. active noise reduction system according to claim 1, it is characterised in that also set up power supply on the left side of the cuboid
Insure (12) and power switch (11)；
The power safety (12) is used for the overcurrent protection of external power source；Power switch (11) the control active noise reduction system
Switch.
4. active noise reduction system according to claim 1, it is characterised in that the digital signal panel is based on
OMAPL137 embedded system and fpga chip, and the plate is provided with two standard serial ports and a 10M/100M network interface.
5. active noise reduction system according to claim 1, it is characterised in that the collection of simulant signal and output board (4)
Comprising：
Two 16bit and sample rate 4M/s AD input channels；
Two 16bit DA output channels；
And input interface (6) can be arranged as required into control source or electric current input pattern.
6. active noise reduction system according to claim 1, it is characterised in that
PC104 of the digital signal panel (5) with collection of simulant signal with output board (4) by two respectively 120 pins
Connector connects, and is fixed on by 8 connection copper posts on heat-dissipating casing on (3).
7. a kind of active denoising method, methods described include：
Step 101) sonic transducer gathers acoustical signal or vibration signal, and the acoustical signal of collection is converted into electric signal；
The electric signal of conversion is carried out Digital Signal Processing by step 102), by the analysis to data signal, including passes through numeral
Filtering obtains the spectrum distribution of signal, analyzes to obtain the intensity distribution of signal by the size of numerical value, and then according to frequency and by force
Degree distinguishes Main Noise Sources and secondary noise source, then according to the feature of main noise signal, is produced by digital to analog conversion module
A raw reverse superposed simulation signal, the superposed signal frequency is identical with noise signal, and opposite in phase, intensity is equal, carries out anti-
To noise reduction；
Wherein, the feature of main noise includes：The frequency and intensity of signal；
Also included before the step 101)：
Noise signal is filtered in different frequency bands by some railway digital wave filters, therefrom analysis draw signal intensity and
The phase place change information of signal；
The signal intensity drawn and phase place change information are subjected to unified contrast, and then obtain noise contributions in all noise signals
Maximum signal, while record the data of all noise signals and carry out probability statistics, and then judge in following a period of time, respectively
The probability that individual noise signal occurs；
Using above-mentioned statistical information, noise reduction process is carried out to caused noise.
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| CN106910492A (en) * | 2017-04-01 | 2017-06-30 | 广州日滨科技发展有限公司 | The noise initiative control method and device of a kind of lift car |
| CN108124219A (en) * | 2017-12-25 | 2018-06-05 | 广州市尊浪电器有限公司 | A kind of noise abatement intelligent sound |
| CN107948831A (en) * | 2017-12-25 | 2018-04-20 | 广州市尊浪电器有限公司 | A kind of sound equipment |
| CN107948872A (en) * | 2017-12-25 | 2018-04-20 | 广州市尊浪电器有限公司 | A kind of WIFI chargings intelligent sound |
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| CN101222786A (en) * | 2006-12-27 | 2008-07-16 | 索尼株式会社 | Sound outputting apparatus, sound outputting method, sound output processing program and system |
| CN101359470A (en) * | 2007-08-03 | 2009-02-04 | 日本电气株式会社 | Chassis with noise cancellation function, noise cancellation method, and method for producing noise cancellation sound data |
| CN102449687A (en) * | 2009-04-28 | 2012-05-09 | 伯斯有限公司 | ANR with adaptive gain |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20030228019A1 (en) * | 2002-06-11 | 2003-12-11 | Elbit Systems Ltd. | Method and system for reducing noise |
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Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101222786A (en) * | 2006-12-27 | 2008-07-16 | 索尼株式会社 | Sound outputting apparatus, sound outputting method, sound output processing program and system |
| CN101359470A (en) * | 2007-08-03 | 2009-02-04 | 日本电气株式会社 | Chassis with noise cancellation function, noise cancellation method, and method for producing noise cancellation sound data |
| CN102449687A (en) * | 2009-04-28 | 2012-05-09 | 伯斯有限公司 | ANR with adaptive gain |
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