CN104791612B - A kind of adaptive noise cancelling arrangement being applied in optical fiber early warning system - Google Patents
A kind of adaptive noise cancelling arrangement being applied in optical fiber early warning system Download PDFInfo
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- CN104791612B CN104791612B CN201510128687.1A CN201510128687A CN104791612B CN 104791612 B CN104791612 B CN 104791612B CN 201510128687 A CN201510128687 A CN 201510128687A CN 104791612 B CN104791612 B CN 104791612B
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Abstract
The embodiment of the invention discloses a kind of adaptive noise cancelling arrangement being applied in optical fiber early warning system, to solve present in prior art it is determined that the especially low technical problem of signal to noise ratio in the signal gathered during the destroyed position of oil-gas pipeline.Adaptive noise cancelling arrangement disclosed by the invention includes mixing optical signal interface, photoelectric conversion unit, sef-adapting filter, the first AD conversion unit, noise signal interface, the second AD conversion unit and digital signal processor, improve the signal to noise ratio of mixing optical signal, so as to ensure that, positioning unit can accurately and fast position noise source according to the signal that digital signal processor exports in optical fiber early warning system, oil-gas pipeline safety is safeguarded, avoids false alarm rate too high.
Description
Technical field
The present invention relates to digital processing field, more particularly to it is a kind of be applied in optical fiber early warning system adaptive making an uproar
Sound canceller.
Background technology
How oil-gas pipeline easily by artificial destruction, accurately determines that the destroyed position of oil-gas pipeline turns into one more
Carry out the problem of more important.
At present, optical fiber sensing technology is gradually applied to determine the destroyed position of oil-gas pipeline during this, still
Due to the analysis and processing for soil vibration signal, contrasted using row mode is entered the methods of such as statistical model to it, but because
Various features are folded, background noise is mixed and disorderly, unlike signal characteristic similarity is larger etc. be present in the soil vibration signal of oil-gas pipeline
Feature, signal to noise ratio is especially low in the signal gathered, and the determination for the position that can not be destroyed for oil-gas pipeline, which provide, accurately to be believed
Breath, then causes false alarm rate too high, causes pipe-line maintenance personnel can not obtain accurate location information, and manpower and materials waste tight
Weight.
Therefore, exist in the prior art it is determined that noise bit in the signal gathered during the destroyed position of oil-gas pipeline
Not low technical problem.
The content of the invention
The embodiment of the present invention by provide it is a kind of be applied to optical fiber early warning system in adaptive noise cancelling arrangement, to
Solve present in prior art it is determined that signal to noise ratio is especially low in the signal gathered during the destroyed position of oil-gas pipeline
Technical problem.
The embodiments of the invention provide a kind of adaptive noise cancelling arrangement being applied in optical fiber early warning system, including：
Optical signal interface is mixed, for receiving the mixed light letter that fiber optic sensor element gathers in the optical fiber early warning system
Number；
Photoelectric conversion unit, it is connected with the mixing optical signal interface, for the mixing optical signal to be converted into mixing
Electric signal；
Sef-adapting filter, it is connected with the photoelectric conversion unit, for being filtered processing to the mixing electric signal,
Mixing electric signal after being handled；
First AD conversion unit, it is connected with the sef-adapting filter, for by the mixing electric signal after the processing
Be converted to hybrid digital signal；
Noise signal interface, for receiving the ambient noise letter of microphone collection corresponding with the fiber optic sensor element
Number；
Second AD conversion unit, it is connected with the noise signal interface, for the ambient noise signal to be converted to
Ambient noise signal；
Digital signal processor, it is connected respectively with first AD conversion unit and second AD conversion unit,
For being handled according to the ambient noise signal the hybrid digital signal, to remove the hybrid digital signal
In ambient noise.
Alternatively, the adaptive noise cancelling arrangement also includes low pass filter, and the low pass filter is arranged at institute
State between noise signal interface and second AD conversion unit, for being filtered processing to the ambient noise signal.
Alternatively, the digital signal processor also includes an output interface, the output interface and the optical fiber early warning
The positioning unit of optical fiber early warning system in system is connected, and is obtained for will remove noise from the hybrid digital signal
Useful signal is output in the positioning unit so that the positioning unit is located according to the useful signal and uses signal source.
Alternatively, the fiber optic sensor element is specially optical fiber acoustic sensor and/or optical fibre vibration sensor.
Alternatively, the photoelectric conversion unit is specially optical signal-electric signal transducer.
Alternatively, first AD conversion unit is specially analog-digital converter.
Alternatively, the digital signal processor according to the ambient noise signal to the hybrid digital signal
When being handled, used algorithm is the LMS algorithm of time change step length parameter.
Alternatively, the variable step μ of the LMS algorithm of time change step length parameter formula is：
The initial step length that wherein μ 1 is taken by algorithm, due to
Then
Alternatively, the LMS algorithm of the time change step length parameter is：
Moment, x (n) was with steady-state error into just according to the input x (n) of wave filter come the step size mu (n) of moment adjustment algorithm
Than μ (n) is then inversely proportional with steady-state error, and with input x (n) gradual increase, the steady-state error of wave filter also can be gradual
During increase, steady-state error is reduced by adjusting step μ (n).
The one or more technical schemes provided in the embodiment of the present invention, have at least the following technical effects or advantages：
1st, as a result of first processing is filtered to mixing optical signal feeding sef-adapting filter, it is re-fed into data signal
The technical scheme handled in processor, the signal to noise ratio of mixing optical signal is improved, be accurately determined for optical fiber early warning system
Signal source, which provides, effectively to be ensured.
2nd, mixing optical signal is handled, it is necessary to be counted according to ambient noise signal as a result of digital signal processor
The function of calculation is simple, and without carrying out matrix operation, arithmetic speed is fast, and precision is high, so as to further increase it is determined that Oil/Gas Pipe
The signal to noise ratio of the signal gathered during the position that road is destroyed, so as to ensure that, positioning unit being capable of essence in optical fiber early warning system
Really, noise source is quickly located, safeguards oil-gas pipeline safety, avoids false alarm rate too high.
Brief description of the drawings
Fig. 1 is the schematic diagram of the adaptive noise cancelling arrangement in optical fiber early warning system provided in an embodiment of the present invention；
Fig. 2 is the structural representation of sef-adapting filter provided in an embodiment of the present invention.
Embodiment
It is existing to solve the invention provides a kind of adaptive noise cancelling arrangement being applied in optical fiber early warning system
It is determined that the especially low technical problem of signal to noise ratio in the signal gathered during the destroyed position of oil-gas pipeline present in technology.
Fig. 1 is refer to, Fig. 1 is the adaptive noise cancelling arrangement in optical fiber early warning system provided in an embodiment of the present invention
Schematic diagram, as shown in figure 1, the adaptive noise cancelling arrangement includes：
Optical signal interface is mixed, for receiving the mixed light letter that fiber optic sensor element gathers in the optical fiber early warning system
Number, fiber optic sensor element is specifically as follows optical fiber acoustic sensor and/or optical fibre vibration sensor, it is of course also possible to be it
His suitable sensor, is not limited herein；In actual applications, fiber optic sensor element can be arranged in oil-gas pipeline and need
The position to be monitored, for example, each fiber optic sensor element has the unique numbering of oneself, so that optical fiber early warning
The signal that system can be passed back according to the fiber optic sensor element, the position of the fiber optic sensor element is determined, in the present embodiment
In, the mixing for the first fiber optic sensor element for being disposed on the first place collection that mixing optical signal interface receives can be set
Optical signal；
Photoelectric conversion unit, it is connected with the mixing optical signal interface, for the mixing optical signal to be converted into mixing
Electric signal, photoelectric conversion unit can be specifically an optical signal-electric signal transducers, so as to by fiber optic sensor element
The optical signal through ovennodulation collected is converted to corresponding electric signal, and in actual applications, optical signal-electric signal transducer is
Used through being used in a variety of occasions, just repeated no more herein；
Sef-adapting filter, it is connected with the photoelectric conversion unit, for being filtered processing to the mixing electric signal,
Mixing electric signal after being handled, in the present embodiment, Fig. 2 is refer to, Fig. 2 is adaptive filter provided in an embodiment of the present invention
The structural representation of ripple device, as shown in Fig. 2 wherein x (n) is the input signal of sef-adapting filter, d (n) is expected response, y
(n) it is the output signal of sef-adapting filter, e (n) is evaluated error, and certainly, in actual applications, sef-adapting filter also wraps
Including adaptive algorithm so that sef-adapting filter can control the filter factor of wave filter according to estimation error signal e (n), after
And sef-adapting filter is realized according to e (n) values " automatically " and adjusts filtering characteristic, just repeats no more herein；
First AD conversion unit, it is connected with the sef-adapting filter, for by the mixing electric signal after the processing
Be converted to hybrid digital signal, the first AD conversion unit is specifically as follows analog-digital converter, and analog-digital converter is otherwise known as A/D
Converter (or ADC；English：Analog to digital converter), it is by sampling, keeping, quantifying and encoding
4 steps, i.e., Time Continuous, amplitude also continuous analog quantity can will be converted to time discrete, amplitude also discrete numeral
Signal, just repeat no more herein；
Noise signal interface, for receiving the ambient noise letter of microphone collection corresponding with the fiber optic sensor element
Number, in the present embodiment, microphone corresponding with fiber optic sensor element refers to the corresponding fibre optical sensor of the microphone
Unit is arranged on same place, and the microphone can be collected near the corresponding fiber optic sensor element site
Ambient noise signal, for example, in the present embodiment, being arranged at first microphone and the first fiber optic sensor element in the first place
Be mutually corresponding to, the environment that the first microphone can collect the first place where first fiber optic sensor element is made an uproar
Sound；
Second AD conversion unit, it is connected with second photoelectric conversion unit, for the ambient noise signal to be turned
Ambient noise signal is changed to, the hardware of the second AD conversion unit is realized can be consistent with the first AD conversion unit, soft
Such as sampled in terms of part, encode and can be adjusted according to actual conditions, to meet the needs of actual conditions, just repeated no more herein
；
Digital signal processor is (referred to as：DSP；English：Digital signal processing), respectively with described
One AD conversion unit is connected with second AD conversion unit, for being mixed according to the ambient noise signal to described
Close data signal to be handled, to remove the ambient noise in the hybrid digital signal.
In specific implementation process, the adaptive noise cancelling arrangement also includes low pass filter, the LPF
Device is arranged between the noise signal interface and second AD conversion unit, for being carried out to the ambient noise signal
Filtering process.
In specific implementation process, the digital signal processor also includes an output interface, the output interface and institute
The positioning unit for stating the optical fiber early warning system in optical fiber early warning system is connected, and is made an uproar for that will be removed from the hybrid digital signal
Sound and the useful signal that obtains are output in the positioning unit so that the positioning unit is located according to the useful signal
With signal source, in the present embodiment, if the signal of digital signal processor output is useful signal, useful signal is to can determine
The signal that oil-gas pipeline has been destroyed, such as the mixed light that digital signal processor is passed back according to the first fiber optic sensor element
The signal for the ambient noise signal output that signal and the first microphone are passed back is useful signal, then optical fiber early warning system being capable of basis
Position where the useful signal determines the first fiber optic sensor element is first position, namely determines that oil-gas pipeline occurs to break
The position of damage.
It should be noted that in the present embodiment, the parameter such as sensitivity to fiber optic sensor element and microphone is not done
Limitation, in actual applications, the technical staff belonging to this area can select suitable fibre optical sensor and microphone, to meet
The demand of actual conditions, is just repeated no more herein.
In the ensuing part of the present embodiment, it will be discussed in detail according to Fig. 1 and Fig. 2 in the embodiment of the present invention to mixing
The processing procedure of optical signal and noise signal, and how to improve it is determined that the letter gathered during the destroyed position of oil-gas pipeline
The process of signal to noise ratio in number.
Please continue to refer to Fig. 1, as shown in figure 1, adaptive noise cancelling arrangement can include stimulus part, at signal
Reason part and segment signal output.
Please continue to refer to Fig. 1, stimulus part is made up of main channel and reference channel, and main channel and reference channel are to letter
Number processing procedure difference it is as follows：In main channel, mixing optical signal interface receives Fibre Optical Sensor in the optical fiber early warning system
The mixing optical signal of device unit collection, mixing optical signal include the monitoring whether normal useful signal of oil-gas pipeline and made an uproar with environment
Acoustical signal, then mixing optical signal is sent into photoelectric conversion unit and is converted to mixing electric signal, is then sent to adaptive
In wave filter, ensure the filter effect of wave filter according to the adaptive characteristic of sef-adapting filter, remove in mixing electric signal
When being gathered because of fiber optic sensor element or electric signal noise caused by transmitting procedure is mixed, then passes through the first analog-to-digital conversion list
Member is converted to hybrid digital signal, and finally hybrid digital signal is sent into digital signal processor；In reference channel, noise
Signaling interface receives the ambient noise signal that corresponding with fiber optic sensor element microphone collects, in the ambient noise signal
Also microphone can be included in collection or the ambient noise signal caused noise in transmitting procedure, and be entered into low pass
In wave filter, the noise in ambient noise signal is removed by low pass filter, the frequency of ambient noise is typically relatively low, passes through low pass
Wave filter can preferably in ambient noise signal be higher than predeterminated frequency signal (this part signal is in ambient noise signal
As noise) decayed, the noise in ambient noise signal is then removed, will finally eliminate the ambient noise signal of noise
It is sent into digital signal processor.
As can be seen that in above process, mixing optical signal and ambient noise signal are distinguished in stimulus part
Carried out filtering process, ensure that the pure of two signals being input in digital signal processor, then for data signal at
The accuracy of the result of reason device output, which provides, effectively to be ensured.
Signal processing includes digital signal processor, and digital signal processor can use the normalization after improving
LMS (English：least mean square；Chinese：Least mean square algorithm) algorithm believes as hybrid digital signal and noisy digit
Number Processing Algorithm, the algorithm can be regarded as the LMS algorithm of time change step length parameter.The algorithm is specially：Moment is according to filtering
The input x (n) of device carrys out the step size mu (n) of moment adjustment algorithm, and x (n) is directly proportional to steady-state error, μ (n) then with steady-state error into
Inverse ratio, with input x (n) gradual increase, the steady-state error of wave filter also can gradually increase, now need to pass through adjusting step
μ (n) reduces steady-state error.Normalized LMS Algorithm is that step size mu is carried out by input vector x (n) squared Euclidean norm
" normalization ".The variable step μ of Normalized LMS Algorithm formula is
μ in formula1The initial step length taken by algorithm, due toWherein λmaxFor x (n) from
The maximum of correlation matrix feature value, thenAlgorithm is necessarily restrained within this range.With input x in formula
(n) square European norm is the initial step length μ 1 that two norms remove algorithm, as the increase of input, variable step μ (n) are gradual
Reduce, the steady-state error of algorithm also accordingly progressively reduces, and has convergence rate quickly and smaller steady-state error.
It is can be seen that by above-mentioned part due to the calculative function letter of the algorithm used in digital signal processor
Single, without carrying out matrix operation, arithmetic speed is fast, and precision is high, so as to further increase it is determined that what oil-gas pipeline was destroyed
The signal to noise ratio of the signal gathered during position, so as to ensure that, noise can be precisely located in positioning unit in optical fiber early warning system
Source, oil-gas pipeline safety is safeguarded, avoid false alarm rate too high.
Segment signal output includes the output interface of digital signal processor, and it can be by digital signal processor from mixing
The useful signal for removing ambient noise signal in data signal and obtaining is output in the positioning unit in optical fiber early warning system, is made
Obtaining positioning unit can cross according to useful signal positioning noise source, just repeat no more herein.
Certainly, in actual applications, the type of signal according to used in positioning unit in optical fiber early warning system is different, can
To set the equipment such as digital analog converter between output interface and positioning unit again, to meet the needs of actual conditions, herein just not
Repeat again.
The one or more technical schemes provided in the embodiment of the present invention, have at least the following technical effects or advantages：
1st, as a result of first processing is filtered to mixing optical signal feeding sef-adapting filter, it is re-fed into data signal
The technical scheme handled in processor, the signal to noise ratio of mixing optical signal is improved, be accurately determined for optical fiber early warning system
Signal source, which provides, effectively to be ensured.
2nd, mixing optical signal is handled, it is necessary to be counted according to ambient noise signal as a result of digital signal processor
The function of calculation is simple, and without carrying out matrix operation, arithmetic speed is fast, and precision is high, so as to further increase it is determined that Oil/Gas Pipe
The signal to noise ratio of the signal gathered during the position that road is destroyed, so as to ensure that, positioning unit can be accurate in optical fiber early warning system
Ground positions noise source, safeguards oil-gas pipeline safety, avoids false alarm rate too high.
Obviously, those skilled in the art can carry out the essence of various changes and modification without departing from the present invention to the present invention
God and scope.So, if these modifications and variations of the present invention belong to the scope of the claims in the present invention and its equivalent technologies
Within, then the present invention is also intended to comprising including these changes and modification.
Claims (6)
- A kind of 1. adaptive noise cancelling arrangement being applied in optical fiber early warning system, it is characterised in that including：Optical signal interface is mixed, for receiving the mixing optical signal that fiber optic sensor element gathers in the optical fiber early warning system；Photoelectric conversion unit, it is connected with the mixing optical signal interface, for the mixing optical signal to be converted into mixing telecommunications Number；Sef-adapting filter, it is connected with the photoelectric conversion unit, for being filtered processing to the mixing electric signal, removes When being gathered in the mixing electric signal because of the fiber optic sensor element or the mixing electric signal is caused by transmitting procedure Noise, the mixing electric signal after being handled；First AD conversion unit, it is connected with the sef-adapting filter, for the mixing electric signal after the processing to be changed For hybrid digital signal；Noise signal interface, for receiving the ambient noise signal of microphone collection corresponding with the fiber optic sensor element；Second AD conversion unit, it is connected with the noise signal interface, for the ambient noise signal to be converted into environment Noisy digit signal；Digital signal processor, it is connected respectively with first AD conversion unit and second AD conversion unit, is used for The hybrid digital signal is handled according to the ambient noise signal, to remove in the hybrid digital signal Ambient noise；Wherein, the digital signal processor is at according to the ambient noise signal to the hybrid digital signal During reason, used algorithm is the LMS algorithm of time change step length parameter, the variable step μ's of the LMS algorithm of the time change step length parameter Formula is：Wherein μ1The initial step length taken by algorithm, due to ThenMoment is according to the input x (n) of wave filter come the step size mu (n) of moment adjustment algorithm, x (n) and stable state Error is directly proportional, and μ (n) is then inversely proportional with steady-state error, and with input x (n) gradual increase, the steady-state error of wave filter When also can gradually increase, steady-state error is reduced by adjusting step μ (n).
- 2. adaptive noise cancelling arrangement as claimed in claim 1, it is characterised in that the adaptive noise cancelling arrangement is also Including low pass filter, the low pass filter be arranged at the noise signal interface and second AD conversion unit it Between, for being filtered processing to the ambient noise signal.
- 3. adaptive noise cancelling arrangement as claimed in claim 1, it is characterised in that the digital signal processor also includes One output interface, the output interface are connected with the positioning unit in the optical fiber early warning system, for will be from the mixed number The useful signal for removing noise in word signal and obtaining is output in the positioning unit so that the positioning unit is according to Useful signal, which is located, uses signal source.
- 4. adaptive noise cancelling arrangement as claimed in claim 1, it is characterised in that the fiber optic sensor element is specially Optical fiber acoustic sensor and/or optical fibre vibration sensor.
- 5. adaptive noise cancelling arrangement as claimed in claim 1, it is characterised in that the photoelectric conversion unit is specially light Signal-electric signal transducer.
- 6. adaptive noise cancelling arrangement as claimed in claim 1, it is characterised in that first AD conversion unit is specific For analog-digital converter.
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5416724A (en) * | 1992-10-09 | 1995-05-16 | Rensselaer Polytechnic Institute | Detection of leaks in pipelines |
| CN101245899A (en) * | 2008-03-21 | 2008-08-20 | 东南大学 | Signal detection device in full optical fiber perturbation sensing and fixing network system |
| CN101556724A (en) * | 2008-04-09 | 2009-10-14 | 中国科学院半导体研究所 | Safety management system of optical fiber perimeter and pattern recognition method thereof |
| CN201866535U (en) * | 2009-12-16 | 2011-06-15 | 北京知容寓远软件科技有限公司 | System for inhibiting pipeline signal noise |
| CN204629114U (en) * | 2015-03-23 | 2015-09-09 | 中国石油天然气集团公司 | A kind of adaptive noise cancelling arrangement be applied in predispersed fiber alarm system |
-
2015
- 2015-03-23 CN CN201510128687.1A patent/CN104791612B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5416724A (en) * | 1992-10-09 | 1995-05-16 | Rensselaer Polytechnic Institute | Detection of leaks in pipelines |
| CN101245899A (en) * | 2008-03-21 | 2008-08-20 | 东南大学 | Signal detection device in full optical fiber perturbation sensing and fixing network system |
| CN101556724A (en) * | 2008-04-09 | 2009-10-14 | 中国科学院半导体研究所 | Safety management system of optical fiber perimeter and pattern recognition method thereof |
| CN201866535U (en) * | 2009-12-16 | 2011-06-15 | 北京知容寓远软件科技有限公司 | System for inhibiting pipeline signal noise |
| CN204629114U (en) * | 2015-03-23 | 2015-09-09 | 中国石油天然气集团公司 | A kind of adaptive noise cancelling arrangement be applied in predispersed fiber alarm system |
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Address after: 100007 Beijing, Dongzhimen, North Street, No. 9, No. Applicant after: China National Petroleum Corporation Applicant after: China Petroleum and Natural Gas Pipeline Bureau Applicant after: China Petroleum & natural gas pipeline communication electric power engineering Co., Ltd. Address before: 100007 Beijing, Dongzhimen, North Street, No. 9, No. Applicant before: China National Petroleum Corporation Applicant before: China Petroleum and Natural Gas Pipeline Bureau Applicant before: China Petroleum & Gas Pipeline Telecommunication & Electricity Engineering Corpo |
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Effective date of registration: 20170216 Address after: 100007 Dongcheng District, Dongzhimen, China, North Street, No. 9 Oil Mansion, No. Applicant after: China National Petroleum Corporation Applicant after: China Petroleum Pipeline Bureau Engineering Co., Ltd. Applicant after: China Petroleum & natural gas pipeline communication electric power engineering Co., Ltd. Address before: 100007 Beijing, Dongzhimen, North Street, No. 9, No. Applicant before: China National Petroleum Corporation Applicant before: China Petroleum and Natural Gas Pipeline Bureau Applicant before: China Petroleum & natural gas pipeline communication electric power engineering Co., Ltd. |
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