CN204629114U - A kind of adaptive noise cancelling arrangement be applied in predispersed fiber alarm system - Google Patents
A kind of adaptive noise cancelling arrangement be applied in predispersed fiber alarm system Download PDFInfo
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Abstract
The utility model embodiment discloses a kind of adaptive noise cancelling arrangement be applied in predispersed fiber alarm system, in order to solve the technical problem that in the signal gathered when determining the position that oil and gas pipes is destroyed that exists in prior art, signal to noise ratio is low especially.Adaptive noise cancelling arrangement disclosed in the utility model comprises mixed light signaling interface, photoelectric conversion unit, sef-adapting filter, the first AD conversion unit, noise signal interface, the second AD conversion unit and DSP digital signal processor, improve the signal to noise ratio of mixed light signal, thus ensure that the signal that in predispersed fiber alarm system, location unit can export according to DSP digital signal processor locates noise source accurately and fast, safeguard oil-gas pipeline safety, avoid false alarm rate too high.
Description
Technical field
The utility model relates to digital processing field, particularly relates to a kind of adaptive noise cancelling arrangement be applied in predispersed fiber alarm system.
Background technique
Oil and gas pipes very easily suffers artificial destruction, how to determine that position that oil and gas pipes is destroyed becomes a more and more important problem accurately.
At present, optical fiber sensing technology is applied in this process of position determining that oil and gas pipes is destroyed gradually, but due to the treatment and analysis for soil vibration signal, adopt as the methods such as statistical model carry out pattern contrast to it, but because there is various features crossover in the soil oscillating signal of oil and gas pipes, background noise is mixed and disorderly, the features such as unlike signal characteristic similarity is larger, in the signal gathered, signal to noise ratio is low especially, the determination of the position that cannot be destroyed for oil and gas pipes provides information accurately, then cause false alarm rate too high, cause pipe-line maintenance personnel cannot obtain location information accurately, manpower and materials waste is serious.
Therefore, there is the technical problem that in the signal gathered when determining the position that oil and gas pipes is destroyed, signal to noise ratio is low especially in prior art.
Model utility content
The utility model embodiment by providing a kind of adaptive noise cancelling arrangement be applied in predispersed fiber alarm system, in order to solve the technical problem that in the signal gathered when determining the position that oil and gas pipes is destroyed that exists in prior art, signal to noise ratio is low especially.
The utility model embodiment provides a kind of adaptive noise cancelling arrangement be applied in predispersed fiber alarm system, comprising:
Mixed light signaling interface, for receiving the mixed light signal that in described predispersed fiber alarm system, fiber optic sensor element gathers;
Photoelectric conversion unit, is connected with described mixed light signaling interface, for described mixed light signal is converted to mixing electrical signal;
Sef-adapting filter, is connected with described photoelectric conversion unit, for carrying out filtering process to described mixing electrical signal, obtains the mixing electrical signal after process;
First AD conversion unit, is connected with described sef-adapting filter, for the mixing electrical signal after described process is converted to hybrid digital signal;
Noise signal interface, for receiving the ambient noise signal that the MIC microphone corresponding with described fiber optic sensor element gathers;
Second AD conversion unit, is connected with described noise signal interface, for described ambient noise signal is converted to ambient noise signal;
DSP digital signal processor, is connected with described second AD conversion unit with described first AD conversion unit respectively, for processing described hybrid digital signal according to described ambient noise signal, to remove the ambient noise in described hybrid digital signal.
Alternatively, described adaptive noise cancelling arrangement also comprises low-pass filter, and described low-pass filter is arranged between described noise signal interface and described second AD conversion unit, for carrying out filtering process to described ambient noise signal.
Alternatively, described DSP digital signal processor also comprises an output interface, described output interface is connected with the location unit of the predispersed fiber alarm system in described predispersed fiber alarm system, useful signal for obtaining removing noise from described hybrid digital signal outputs in described location unit, described location unit is positioned with according to described useful signal and uses signal source.
Alternatively, described fiber optic sensor element is specially optical fiber acoustic sensor and/or optical fibre vibration sensor.
Alternatively, described photoelectric conversion unit is specially optical signal-electric signal transducer.
Alternatively, described first AD conversion unit is specially analog-digital converter.
The one or more technological schemes provided in the utility model embodiment, at least have following technique effect or advantage:
1, first filtering process is carried out to mixed light signal feeding sef-adapting filter owing to have employed, send into the technological scheme carrying out in DSP digital signal processor processing again, improve the signal to noise ratio of mixed light signal, accurately determine that signal source provides for predispersed fiber alarm system and effectively ensure.
2, due to have employed DSP digital signal processor environmentally noise signal mixed light signal is processed, calculative function is simple, without the need to carrying out matrix operation, fast operation, precision is high, thus further increases the signal to noise ratio of the signal gathered when determining the position that oil and gas pipes is destroyed, thus ensure that in predispersed fiber alarm system, location unit can locate noise source accurately and fast, safeguard oil-gas pipeline safety, avoid false alarm rate too high.
Accompanying drawing explanation
The schematic diagram of the adaptive noise cancelling arrangement in the predispersed fiber alarm system that Fig. 1 provides for the utility model embodiment;
The structural representation of the sef-adapting filter that Fig. 2 provides for the utility model embodiment.
Embodiment
The utility model provides a kind of adaptive noise cancelling arrangement be applied in predispersed fiber alarm system, in order to solve the technical problem that in the signal gathered when determining the position that oil and gas pipes is destroyed that exists in prior art, signal to noise ratio is low especially.
Please refer to Fig. 1, the schematic diagram of the adaptive noise cancelling arrangement in the predispersed fiber alarm system that Fig. 1 provides for the utility model embodiment, as shown in Figure 1, this adaptive noise cancelling arrangement comprises:
Mixed light signaling interface, for receiving the mixed light signal that in described predispersed fiber alarm system, fiber optic sensor element gathers, fiber optic sensor element is specifically as follows optical fiber acoustic sensor and/or optical fibre vibration sensor, certainly, also can be other suitable sensors, not limit at this; In actual applications, fiber optic sensor element can be arranged in oil and gas pipes the position needing to carry out monitoring, such as, each fiber optic sensor element has oneself unique numbering, thus make the signal that predispersed fiber alarm system can be passed back according to this fiber optic sensor element, determine the position of this fiber optic sensor element, in the present embodiment, what can set the reception of mixed light signaling interface is the mixed light signal that the first fiber optic sensor element being arranged at the first place gathers;
Photoelectric conversion unit, be connected with described mixed light signaling interface, for described mixed light signal is converted to mixing electrical signal, photoelectric conversion unit can be specifically an optical signal-electric signal transducer, thus the optical signal through overmodulation that fiber optic sensor element can be collected is converted to corresponding electrical signal, in actual applications, optical signal-electric signal transducer has been used in multiple occasion and has been used, and has just repeated no more at this;
Sef-adapting filter, be connected with described photoelectric conversion unit, for carrying out filtering process to described mixing electrical signal, obtain the mixing electrical signal after process, in the present embodiment, please refer to Fig. 2, the structural representation of the sef-adapting filter that Fig. 2 provides for the utility model embodiment, as shown in Figure 2, wherein x (n) input signal that is sef-adapting filter, d (n) is Expected Response, the output signal that y (n) is sef-adapting filter, e (n) is evaluated error, certainly, in actual applications, sef-adapting filter also comprises adaptive algorithm, make sef-adapting filter can control the filter factor of wave filter according to estimation error signal e (n), then sef-adapting filter is made can to realize according to e (n) value " automatically " adjustment filter characteristics, just repeat no more at this,
First AD conversion unit, be connected with described sef-adapting filter, for the mixing electrical signal after described process is converted to hybrid digital signal, the first AD conversion unit is specifically as follows analog-digital converter, analog-digital converter be otherwise known as A/D converter (or claim ADC; English: analog to digital converter), it is by 4 steps such as sampling, maintenance, quantification and codings, namely can just Time Continuous, amplitude also continuous print analog amount be converted to the also discrete digital signal of time discrete, amplitude, just repeated no more at this;
Noise signal interface, for receiving the ambient noise signal that the MIC microphone corresponding with described fiber optic sensor element gathers, in the present embodiment, the MIC microphone corresponding with fiber optic sensor element refers to that the fiber optic sensor element that this MIC microphone and its are corresponding is arranged on same place, this MIC microphone can collect the ambient noise signal near this fiber optic sensor element site corresponding with it, such as, in the present embodiment, the first MIC microphone being arranged at the first place is mutually corresponding with the first fiber optic sensor element, first MIC microphone can collect the ambient noise in first place at this first fiber optic sensor element place,
Second AD conversion unit, be connected with described second photoelectric conversion unit, for described ambient noise signal is converted to ambient noise signal, the hardware implementing of the second AD conversion unit can be consistent with the first AD conversion unit, software aspect such as sampling, coding etc. can adjust according to actual conditions, to meet the needs of actual conditions, just repeat no more at this;
DSP digital signal processor (is called for short: DSP; English: digital signal processing), be connected with described second AD conversion unit with described first AD conversion unit respectively, for processing described hybrid digital signal according to described ambient noise signal, to remove the ambient noise in described hybrid digital signal.
In specific implementation process, described adaptive noise cancelling arrangement also comprises low-pass filter, and described low-pass filter is arranged between described noise signal interface and described second AD conversion unit, for carrying out filtering process to described ambient noise signal.
In specific implementation process, described DSP digital signal processor also comprises an output interface, described output interface is connected with the location unit of the predispersed fiber alarm system in described predispersed fiber alarm system, useful signal for obtaining removing noise from described hybrid digital signal outputs in described location unit, described location unit is made to be positioned with by signal source according to described useful signal, in the present embodiment, if the signal that DSP digital signal processor exports is useful signal, useful signal is the signal can determining that oil and gas pipes has been destroyed, the mixed light signal that such as DSP digital signal processor is passed back according to the first fiber optic sensor element and the signal that the ambient noise signal that the first MIC microphone is passed back exports are useful signal, then according to this useful signal, predispersed fiber alarm system can determine that the position at the first fiber optic sensor element place is primary importance, also namely determine that damaged position occurs oil and gas pipes.
It should be noted that, in the present embodiment, the parameters such as the sensitivity of fiber optic sensor element and MIC microphone are not limited, in actual applications, technician belonging to related domain can select suitable optical fiber transducer and MIC microphone, to meet the demand of actual conditions, has just repeated no more at this.
In the ensuing part of the present embodiment, will according to Fig. 1 and Fig. 2, introduce the processing procedure to mixed light signal and noise signal in the utility model embodiment in detail, and how to improve the process of signal to noise ratio in the signal that gathers when determining the position that oil and gas pipes is destroyed.
Please continue to refer to Fig. 1, as shown in Figure 1, adaptive noise cancelling arrangement can comprise stimulus part, signal processing and segment signal output.
Please continue to refer to Fig. 1, stimulus part is made up of main passage and reference channel, main passage and reference channel are distinguished as follows to the processing procedure of signal: in main passage, mixed light signaling interface receives the mixed light signal that in described predispersed fiber alarm system, fiber optic sensor element gathers, mixed light signal comprises the whether normal useful signal of monitoring oil and gas pipes and ambient noise signal, then mixed light signal is sent in photoelectric conversion unit and be converted to mixing electrical signal, then sent in sef-adapting filter, the filter effect of wave filter is ensured according to the adaptive characteristic of sef-adapting filter, remove in mixing electrical signal because of when fiber optic sensor element gathers or mix the noise that produces in transmitting procedure of electrical signal, hybrid digital signal is converted to again by the first AD conversion unit, finally hybrid digital signal is sent in DSP digital signal processor, in reference channel, the ambient noise signal that the MIC microphone that noise signal interface is corresponding with fiber optic sensor element collects, also MIC microphone can be comprised when gathering or the noise that produces in transmitting procedure of this ambient noise signal in this ambient noise signal, and be entered in low-pass filter, the noise in ambient noise signal is removed by low-pass filter, the frequency of ambient noise is general lower, can be decayed to the signal (this part signal is noise in ambient noise signal) higher than predeterminated frequency in ambient noise signal preferably by low-pass filter, then the noise in ambient noise signal is removed, finally the ambient noise signal eliminating noise is sent in DSP digital signal processor.
Can find out, in above process, namely respectively filtering process has been carried out to mixed light signal and ambient noise signal at stimulus part, ensure that the pure of two signals be input in DSP digital signal processor, the accuracy of result then exported for DSP digital signal processor provides and effectively ensures.
Signal processing comprises DSP digital signal processor, and DSP digital signal processor can adopt the Normalized LMS after improvement (English: least mean square; Chinese: least mean square algorithm) algorithm is as the Processing Algorithm of hybrid digital signal and noisy digit signal, and this algorithm can be regarded as the LMS algorithm of time change step length parameter.This algorithm is specially: the moment carrys out the step size mu (n) of moment adjustment algorithm according to input x (n) of wave filter, x (n) is directly proportional to steady-state error, μ (n) is then inversely proportional to steady-state error, along with the increase gradually of input x (n), the steady-state error of wave filter also can increase gradually, now needs to reduce steady-state error by adjustment step size mu (n).Normalized LMS Algorithm is carried out " normalization " step size mu by the squared Euclidean norm of input vector x (n).The formula of the variable step μ of Normalized LMS Algorithm is
μ in formula
1for the initial step length that algorithm is got, due to
wherein λ
maxfor the maximum value of the autocorrelation matrix eigenvalue of x (n), then
within the scope of this, algorithm is necessarily restrained.The initial step length μ 1 of algorithm is removed by square European norm of input x (n) i.e. two norms in formula, along with the increase of input, variable step μ (n) reduction gradually, the steady-state error of algorithm is also corresponding progressively to be reduced, and has very fast convergence rate and less steady-state error.
Can be found out by above-mentioned part, because the calculative function of the algorithm adopted in DSP digital signal processor is simple, without the need to carrying out matrix operation, fast operation, precision is high, thus further increases the signal to noise ratio of the signal gathered when determining the position that oil and gas pipes is destroyed, thus ensure that in predispersed fiber alarm system, location unit accurately can locate noise source, safeguard oil-gas pipeline safety, avoid false alarm rate too high.
Segment signal output comprises the output interface of DSP digital signal processor, its useful signal DSP digital signal processor can removed ambient noise signal from hybrid digital signal and obtain outputs in the location unit in predispersed fiber alarm system, location unit can be crossed according to this useful signal location noise source, just repeated no more at this.
Certainly, in actual applications, according to the type difference of the signal that location unit in predispersed fiber alarm system uses, again between output interface and location unit, the equipment such as digital to analog converter can be set, to meet the demand of actual conditions, just repeat no more at this.
The one or more technological schemes provided in the utility model embodiment, at least have following technique effect or advantage:
1, first filtering process is carried out to mixed light signal feeding sef-adapting filter owing to have employed, send into the technological scheme carrying out in DSP digital signal processor processing again, improve the signal to noise ratio of mixed light signal, accurately determine that signal source provides for predispersed fiber alarm system and effectively ensure.
2, due to have employed DSP digital signal processor environmentally noise signal mixed light signal is processed, calculative function is simple, without the need to carrying out matrix operation, fast operation, precision is high, thus further increases the signal to noise ratio of the signal gathered when determining the position that oil and gas pipes is destroyed, thus ensure that in predispersed fiber alarm system, location unit accurately can locate noise source, safeguard oil-gas pipeline safety, avoid false alarm rate too high.
Obviously, those skilled in the art can carry out various change and modification to the utility model and not depart from spirit and scope of the present utility model.Like this, if these amendments of the present utility model and modification belong within the scope of the utility model claim and equivalent technologies thereof, then the utility model is also intended to comprise these change and modification.
Claims (6)
1. be applied to the adaptive noise cancelling arrangement in predispersed fiber alarm system, it is characterized in that, comprising:
Mixed light signaling interface, for receiving the mixed light signal that in described predispersed fiber alarm system, fiber optic sensor element gathers;
Photoelectric conversion unit, is connected with described mixed light signaling interface, for described mixed light signal is converted to mixing electrical signal;
Sef-adapting filter, is connected with described photoelectric conversion unit, for carrying out filtering process to described mixing electrical signal, obtains the mixing electrical signal after process;
First AD conversion unit, is connected with described sef-adapting filter, for the mixing electrical signal after described process is converted to hybrid digital signal;
Noise signal interface, for receiving the ambient noise signal that the MIC microphone corresponding with described fiber optic sensor element gathers;
Second AD conversion unit, is connected with described noise signal interface, for described ambient noise signal is converted to ambient noise signal;
DSP digital signal processor, is connected with described second AD conversion unit with described first AD conversion unit respectively, for processing described hybrid digital signal according to described ambient noise signal, to remove the ambient noise in described hybrid digital signal.
2. adaptive noise cancelling arrangement as claimed in claim 1, it is characterized in that, described adaptive noise cancelling arrangement also comprises low-pass filter, described low-pass filter is arranged between described noise signal interface and described second AD conversion unit, for carrying out filtering process to described ambient noise signal.
3. adaptive noise cancelling arrangement as claimed in claim 1, it is characterized in that, described DSP digital signal processor also comprises an output interface, described output interface is connected with the location unit in described predispersed fiber alarm system, useful signal for obtaining removing noise from described hybrid digital signal outputs in described location unit, described location unit is positioned with according to described useful signal and uses signal source.
4. adaptive noise cancelling arrangement as claimed in claim 1, it is characterized in that, described 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 characterized in that, described photoelectric conversion unit is specially optical signal-electric signal transducer.
6. adaptive noise cancelling arrangement as claimed in claim 1, it is characterized in that, described first AD conversion unit is specially analog-digital converter.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104791612A (en) * | 2015-03-23 | 2015-07-22 | 中国石油天然气集团公司 | Adaptive noise cancellation device applied to optical fiber early warning system |
| CN115479219A (en) * | 2022-09-20 | 2022-12-16 | 无锡科晟光子科技有限公司 | Intelligent pipeline state monitoring method and device and intelligent pipeline system |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104791612A (en) * | 2015-03-23 | 2015-07-22 | 中国石油天然气集团公司 | Adaptive noise cancellation device applied to optical fiber early warning system |
| CN104791612B (en) * | 2015-03-23 | 2017-12-05 | 中国石油天然气集团公司 | A kind of adaptive noise cancelling arrangement being applied in optical fiber early warning system |
| CN115479219A (en) * | 2022-09-20 | 2022-12-16 | 无锡科晟光子科技有限公司 | Intelligent pipeline state monitoring method and device and intelligent pipeline system |
| CN115479219B (en) * | 2022-09-20 | 2024-03-01 | 无锡科晟光子科技有限公司 | Intelligent pipeline state monitoring method, monitoring device and intelligent pipeline system |
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Address after: 100007 Beijing, Dongzhimen, North Street, No. 9, No. Patentee after: China National Petroleum Corp. Patentee after: CHINA PETROLEUM PIPELINE BUREAU Patentee after: CHINA PETROLEUM AND NATURAL GAS PIPELINE COMMUNICATION POWER ENGINEERING Co.,Ltd. Address before: 100007 Beijing, Dongzhimen, North Street, No. 9, No. Patentee before: China National Petroleum Corp. Patentee before: CHINA PETROLEUM PIPELINE BUREAU Patentee before: China Petroleum Pipeline Communication Power Engineering Corp. |
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Effective date of registration: 20170220 Address after: 100007 Dongcheng District, Dongzhimen, China, North Street, No. 9 Oil Mansion, No. Patentee after: China National Petroleum Corp. Patentee after: China Petroleum Pipeline Engineering Co.,Ltd. Patentee after: CHINA PETROLEUM AND NATURAL GAS PIPELINE COMMUNICATION POWER ENGINEERING Co.,Ltd. Address before: 100007 Beijing, Dongzhimen, North Street, No. 9, No. Patentee before: China National Petroleum Corp. Patentee before: CHINA PETROLEUM PIPELINE BUREAU Patentee before: CHINA PETROLEUM AND NATURAL GAS PIPELINE COMMUNICATION POWER ENGINEERING Co.,Ltd. |
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