CN102359797A - System and method for reducing noise of phase generated carrier (PGC) system in optical fiber hydrophone - Google Patents
System and method for reducing noise of phase generated carrier (PGC) system in optical fiber hydrophone Download PDFInfo
- Publication number
- CN102359797A CN102359797A CN2011101917194A CN201110191719A CN102359797A CN 102359797 A CN102359797 A CN 102359797A CN 2011101917194 A CN2011101917194 A CN 2011101917194A CN 201110191719 A CN201110191719 A CN 201110191719A CN 102359797 A CN102359797 A CN 102359797A
- Authority
- CN
- China
- Prior art keywords
- signal
- demodulation
- noise
- demodulation module
- module
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Images
Landscapes
- Measurement Of Mechanical Vibrations Or Ultrasonic Waves (AREA)
- Gyroscopes (AREA)
Abstract
The invention relates to the field of optical fiber hydrophones, in particular to a system and a method for reducing noise of a phase generated carrier (PGC) system in an optical fiber hydrophone. The system comprises a modulator (0), a laser (1), a 1*2 coupler (2), a sensing probe (3), a reference probe (4), a first demodulation module (501), a second demodulation module (502) and a decorrelation module (6), wherein the modulator (0) is connected with the laser (1); the laser (1) is connected with the 1*2 coupler (2); the 1*2 coupler (2) is connected with the sensing probe (3) and the reference probe (4); the sensing probe (3) is connected with the first demodulation module (501); the reference probe (4) is connected with the second demodulation module (502); and the first demodulation module (501) and the second demodulation module (502) are connected with the decorrelation module (6). The system can improve the noise performance of the hydrophone.
Description
Technical field
The present invention relates to the fibre optic hydrophone field, be specifically related to a kind of system and method that is used for fibre optic hydrophone PGC system noise reduction.
Background technology
The fibre optic hydrophone system comprises light source input, modulating part, transducing part and demodulation part, and PGC is a kind of modulation system of modulating part, and the system of modulating with PGC is called the PGC system.The performance index of Scale Fiber-Optic Hydrophone Array comprise system's self noise, dynamic range, multiplexing scale and primitive sensitivity etc.Adopt the dynamic range of the Scale Fiber-Optic Hydrophone Array of PGC (Phase Generated Carrier, phase generated carrier) scheme mainly to determine by carrier frequency and Noise Background.The research noiseproof feature, reduction noise scheme reasonable in design, making noise objective meet the demands is the research content of interference type optical fiber hydrophone array.For the PGC system that adopts non-equilibrium interferometer, the phase noise of light source is the main source of its output noise.In PGC SDM system (being meant the PGC system of space division multiplexing mode); The output result of different sensing units occupies an leading position with source noise, a kind of thinking of optimization system noiseproof feature be eliminate between the different sensing units same source noise---this process is called decorrelation.
Existent method is an insensitive reference probe of utilizing one 2 * 2 coupling mechanism to process at present, and it is carried out demodulation, then the demodulation result of sensing probe and reference probe is subtracted each other, and removes same source noise.This method causes the result of decorrelation undesirable because the degree of correlation of two paths of signals is unstable.
Summary of the invention
The technical matters that (one) will solve
The technical matters that the present invention will solve is: the noiseproof feature that how to improve nautical receiving set.
(2) technical scheme
For solving the problems of the technologies described above; The invention provides a kind of system that is used for fibre optic hydrophone PGC system noise reduction, comprising: modulator, laser instrument, 1 * 2 coupling mechanism, sensing probe, reference probe, first demodulation module, second demodulation module, de-correlation modules; Said first demodulation module is used for the sensing path signal of said 1 * 2 coupling mechanism output is carried out demodulation through the light signal that is returned after the sensing probe, and said second demodulation module is used for the reference arm signal of said 1 * 2 coupling mechanism output is carried out demodulation through the light signal that is returned after the reference probe; Said de-correlation modules is used for the signal that said first demodulation module, second demodulation module are exported is carried out the decorrelation computing to remove same source noise, obtains exporting signal;
Wherein, Said modulator is connected with laser instrument; Said laser instrument is connected with 1 * 2 coupling mechanism, and said 1 * 2 coupling mechanism is connected with reference probe with said sensing probe respectively, and said sensing probe is connected with said first demodulation module; Said reference probe is connected with said second demodulation module, and said first demodulation module all is connected with de-correlation modules with second demodulation module.
Preferably, said sensing probe comprises 2 * 2 coupling mechanisms and first faraday's rotating mirror, and said 2 * 2 coupling mechanisms are connected with said first demodulation module; Said reference probe comprises 3 * 2 coupling mechanisms and second faraday's rotating mirror, and said 3 * 2 coupling mechanisms are connected with said second demodulation module.
Preferably, said de-correlation modules comprises linear transform module and the 3rd demodulation module that connects successively, and said linear transform module is used for the two-way output signal of said 3x2 coupling mechanism is carried out linear combination, obtains composite signal; Said the 3rd demodulation module is used for said composite signal is carried out demodulation.
The present invention also provides a kind of method of utilizing described system to carry out PGC system noise reduction in the fibre optic hydrophone, comprises step:
S1, the light of modulating through said modulator frequency that said laser instrument is sent are imported said 1 * 2 coupling mechanism and are carried out space division multiplexing, and a road of output is the sensing path signal, and another road is the reference arm signal;
S2, said sensing path signal and reference arm signal carry out demodulation through first demodulation module and second demodulation module respectively through the light that is returned after sensing probe and the reference probe respectively; Carry out the decorrelation computing to remove same source noise by de-correlation modules then, obtain exporting signal.
Separate timing among the step S2, used demodulation method is digital arc tangent demodulation method, and the sensing path signal that obtains after the demodulation and the demodulation result of reference arm signal are respectively:
Wherein,
Be the phase information of sensing path signal,
Being the noise of sensing path signal, is phase noise
Light intensity noise n
i, circuit noise
Parameter in said system
C
sUnder pass through digitizing arc tangent demodulation result;
Be the phase information of reference arm signal,
Being the reference arm noise, is phase noise
Light intensity noise n
i, circuit noise
Parameter in said system
C
rUnder pass through digitizing arc tangent demodulation result;
Be the output of additivity light intensity noise in the demodulation result.
To carry out the step of computing following for de-correlation modules among the step S2:
The two-way of 3x2 coupling mechanism output signal is carried out linear combination obtains composite signal i, make the information that comprises the phase place
of sensing path signal in the phase place of composite signal:
Wherein, i
R1Be the first via of the two-way output signal of 3x2 coupling mechanism, i
R2Be the second the tunnel, K is the splitting ratio of coupling mechanism;
Then said composite signal i is carried out demodulation, obtains phase value and be:
Wherein,
Wherein
Be a fixing phase differential of the two-way output signal of 3 * 2 coupling mechanisms, because C
r≈ C
sSo, have:
The signal that carries out among the step S2 exporting after the decorrelation computing is following:
(3) beneficial effect
The present invention is through introducing one 3 * 2 coupling mechanism in the system of PGC space division multiplexing; Utilize the characteristics that have fixed skew between its two-way reference signal; Realized tracking to the transducing signal phase place; And realized de-correlation whereby, and reached and eliminated purpose with source noise, make the noiseproof feature of nautical receiving set obtain very big improvement." phase control act " of the present invention decorrelation system can eliminate the phase noise of being introduced by light source fully, and its cost is that circuit noise and light intensity noise improve 8.5dB, 14dB respectively at most.Because circuit noise and light path noise ratio are lower in the system usually, this system still can effectively reduce the overall noise of system.
Description of drawings
Fig. 1 is a system architecture synoptic diagram of the present invention;
Fig. 2 is a method flow diagram of the present invention;
Fig. 3 is the program flow diagram of the method for Fig. 2 when realizing with FPGA;
Fig. 4 is the experimental provision structural drawing of the feasibility of proof diagram 1 system;
Fig. 5 is an experimental result picture, i.e. the decorrelation of 9812 capture cards is figure as a result.
Among the figure, 0: modulator; 1: laser instrument; 2:1 * 2 coupling mechanisms; 3: sensing probe; 301:2 * 2 coupling mechanisms; 302: the first faraday's rotating mirrors; 4, reference probe; 401:3 * 2 coupling mechanisms; 402: the second faraday's rotating mirrors; 501: the first demodulation modules; 502: the second demodulation modules; 6: de-correlation modules; 601: linear transform module; 602: the three demodulation modules.
Embodiment
Below in conjunction with accompanying drawing and embodiment, specific embodiments of the invention describes in further detail.Following examples are used to explain the present invention, but are not used for limiting scope of the present invention.
The present invention proposes the method for the multichannel sensing probe of a kind of PGC of elimination system with source noise, and has designed the noise reduction system to the PGC SDM system.The degree of correlation is big more, and the effect of decorrelation is good more.In order to obtain stable decorrelation effect, need the degree of correlation of control multiplex system.
As shown in Figure 1, system comprises modulator 0, laser instrument 1,1 * 2 coupling mechanism 2, sensing probe 3, reference probe 4, first demodulation module 501, second demodulation module 502, de-correlation modules 6; Said first demodulation module 501 is used for the sensing path signal of said 1 * 2 coupling mechanism 2 outputs is carried out demodulation through the light that is returned after the sensing probe 3, and said second demodulation module 502 is used for the reference arm signal of said 1 * 2 coupling mechanism 2 outputs is carried out demodulation through the light signal that is returned after the reference probe 3; Said de-correlation modules 6 is used for the signal that said first demodulation module 501, second demodulation module 502 are exported is carried out the decorrelation computing to remove same source noise, obtains exporting signal
Wherein, Modulator 0 is connected with laser instrument 1; Said laser instrument 1 is connected with 1 * 2 coupling mechanism 2, and said 1 * 2 coupling mechanism 2 is connected with reference probe 4 with said sensing probe 3 respectively, and said sensing probe 3 is connected with said first demodulation module 501; Said reference probe 4 is connected with said second demodulation module 502, and said first demodulation module 501 all is connected with de-correlation modules 6 with second demodulation module 502.
Sensing probe 3 comprises 2 * 2 coupling mechanisms 301 and first faraday's rotating mirror 302, and said 2 * 2 coupling mechanisms 301 are connected with said first demodulation module 501; Said reference probe 4 comprises 3 * 2 coupling mechanisms 401 and second faraday's rotating mirror 402, and said 3 * 2 coupling mechanisms 401 are connected with said second demodulation module 502.
De-correlation modules 6 comprises linear transform module 601 and the 3rd demodulation module 602 that connects successively, and said linear transform module 601 is used for the two-way output signal of said 3x2 coupling mechanism 401 is carried out linear combination, obtains composite signal; Said the 3rd demodulation module 602 is used for said composite signal is carried out demodulation.
According to theoretical analysis; The factor that influences the two paths of signals degree of correlation is that depth of modulation C and the direct current phase place
of two-way sensor is because in multiplex system; Can control depth of modulation C through the arm length difference of adjustment nautical receiving set interferometer; And the direct current phase place is difficult to directly control owing to receive the effect of environmental factors such as temperature, pressure.In order to improve the degree of correlation, must control the direct current phase place of two-way sensor, " phase control act " as follows proposed for this reason, principle is as shown in Figure 1.
The light that light source sends is imported 1 * 2 coupling mechanism (realization space division multiplexing) through frequency modulation (PFM), and one the tunnel is sensing path, and one the tunnel is reference arm.The signal that the two-way probe returns carries out the decorrelation computing through demodulation, removes same source noise, obtains final output signal.The key of " phase control act " is the use of 3 * 2 coupling mechanisms, and the two-way output signal of 3 * 2 coupling mechanisms has a fixing phase differential
and can utilize this principle to realize the tracking to the sensing path phase place.As shown in Figure 2, method concrete steps of the present invention are following:
S1, cross light input 1 * 2 coupling mechanism 2 through said modulator 0 frequency modulation (PFM) and carry out space division multiplexing what said laser instrument 1 sent, a road of output is the sensing path signal, and another road is the reference arm signal;
S2, said sensing path signal and reference arm signal carry out demodulation through first demodulation module 501 and second demodulation module 502 respectively through the light signal that is returned after sensing probe 3 and the reference probe 4 respectively; Carry out the decorrelation computing to remove same source noise by de-correlation modules 6 then, obtain final output signal.
Signal to sensing path and reference arm is separated timing; Used demodulation method is digital arc tangent demodulation method; Only need one (another can be calculated by
) in the signal of two arms of demodulation reference arm, the demodulation result that obtains sensing path and reference arm is:
Wherein,
Be the phase information of sensing path signal,
Being the noise of sensing path, is phase noise
Light intensity noise n
i, circuit noise
In systematic parameter
C
sUnder pass through DAT (Digital Arc-Tangent, digitizing arc tangent) demodulation result;
Be the phase information of reference arm signal,
Being the reference arm noise, is phase noise
Light intensity noise n
i, circuit noise
In systematic parameter
C
rUnder pass through the DAT demodulation result;
Be the output of additivity light intensity noise in the demodulation result.
To carry out the step of computing following for de-correlation modules among the step S2:
The two-way of 601 pairs of 3x2 coupling mechanisms of linear transform module output signal carries out linear combination and obtains composite signal i, makes the information that comprises the phase place
of sensing path signal in the phase place of composite signal:
Wherein, i
R1Be the first via of the two-way output signal of 3x2 coupling mechanism, i
R2Be the second the tunnel, K is the splitting ratio of coupling mechanism;
Utilize 602 pairs of combinations thereof signals of the 3rd demodulation module to carry out demodulation then, demodulation obtains phase value and does
Wherein,
In real system, C
r≈ C
sSo, have
Obtain exporting signal then:
n
cThe circuit noise of being exported signal by the two-way of reference probe combines, and its power spectrum density is:
The circuit noise of sensing path and reference arm spectrum is consistent in the real system.
Expression formula by γ can know,
Through theoretical analysis, " phase control act " decorrelation system can eliminate the phase noise of being introduced by light source fully, and this is the advantage place of this patent.Its cost is that circuit noise and light intensity noise improve 8.5dB, 14dB respectively at most.Because circuit noise and light path noise ratio are lower in the system usually, this method still can effectively reduce the overall noise of system.
The FPGA program flow diagram of above-mentioned algorithm is as shown in Figure 3:
With respect to existing system, the new procedures structure increases a DAT module, linear transform module, time delay module and subtraction block at each sensing path.Wherein resource consumption is the low-pass filter of taking advantage of in the DAT module behind the carrier wave to the maximum; When FPGA realizes; 8 road train of signals low pass filter blocks of passing through; So divide in the octuple system at sky, whole only need to increase a public low pass filter blocks (about 100 rank)---can ignore anti-aliasing filter (200～300 rank) and the high-pass filtering (being higher than 500 rank) of this resource consumption before data output.The effect of time delay module is an align data, and the number of always delaying time is linear transform module and DAT module time-delay sum.
Be the feasibility of checking " phase control act " decorrelation system, a kind of practicable scheme is as shown in Figure 3.The experimental apparatus that adopts has: RIO narrow linewidth laser, 10.6 meters arm length difference nautical receiving set (2 * 2 coupling mechanisms; Be the sensing probe among Fig. 3), 10.6m arm length difference nautical receiving set (3 * 2 coupling mechanisms, i.e. reference probe among Fig. 3), 9812 capture cards (sampling rate 200kHz), PXI446124 position DA (carrier frequency 20kHz).Experimental result is seen Fig. 4, draws to draw a conclusion:
1. directly the decorrelation result can suppress the low frequency 1/f noise, but can not reduce the above noise spectrum of 1kHz;
2. " phase control act " decorrelation result has eliminated the low frequency 1/f noise fully, reduces high frequency noise 15dB simultaneously;
3. the circuit system noise source is AD noise and photoelectric switching circuit noise, and wherein the photoelectric switching circuit noise is higher than the AD noise, and for about-102dB/Hz, the decorrelation result is-95dB/Hz to exceed circuit noise 7dB, with theoretical identical with simulation result.
The above only is a preferred implementation of the present invention; Should be pointed out that for those skilled in the art, under the prerequisite that does not break away from know-why of the present invention; Can also make some improvement and modification, these improve and modification also should be regarded as protection scope of the present invention.
Claims (7)
1. system that is used for fibre optic hydrophone PGC system noise reduction; It is characterized in that, comprising: modulator (0), laser instrument (1), 1 * 2 coupling mechanism (2), sensing probe (3), reference probe (4), first demodulation module (501), second demodulation module (502), de-correlation modules (6); Said first demodulation module (501) is used for the sensing path signal of said 1 * 2 coupling mechanism (2) output is carried out demodulation through the light signal that sensing probe (3) is returned afterwards, and said second demodulation module (502) is used for the light signal that the reference arm signal process reference probe (3) of said 1 * 2 coupling mechanism (2) output is returned is afterwards carried out demodulation; Said de-correlation modules (6) is used for the signal that said first demodulation module (501), second demodulation module (502) are exported is carried out the decorrelation computing to remove same source noise, obtains exporting signal;
Wherein, Said modulator (0) is connected with laser instrument (1); Said laser instrument (1) is connected with 1 * 2 coupling mechanism (2), and said 1 * 2 coupling mechanism (2) is connected with reference probe (4) with said sensing probe (3) respectively, and said sensing probe (3) is connected with said first demodulation module (501); Said reference probe (4) is connected with said second demodulation module (502), and said first demodulation module (501) all is connected with de-correlation modules (6) with second demodulation module (502).
2. the system of claim 1 is characterized in that, said sensing probe (3) comprises 2 * 2 coupling mechanisms (301) and first faraday's rotating mirror (302), and said 2 * 2 coupling mechanisms (301) are connected with said first demodulation module (501); Said reference probe (4) comprises 3 * 2 coupling mechanisms (401) and second faraday's rotating mirror (402), and said 3 * 2 coupling mechanisms (401) are connected with said second demodulation module (502).
3. system as claimed in claim 2; It is characterized in that; Said de-correlation modules (6) comprises linear transform module (601) and the 3rd demodulation module (602) that connects successively; Said linear transform module (601) is used for the two-way output signal of said 3x2 coupling mechanism (401) is carried out linear combination, obtains composite signal; Said the 3rd demodulation module (602) is used for said composite signal is carried out demodulation.
4. a method of utilizing claim 1 or 2 or 3 described systems to carry out PGC system noise reduction in the fibre optic hydrophone is characterized in that, comprises step:
S1, the light through said modulator (0) frequency modulation (PFM) that said laser instrument (1) is sent are imported said 1 * 2 coupling mechanism (2) and are carried out space division multiplexing, and a road of output is the sensing path signal, and another road is the reference arm signal;
S2, said sensing path signal and reference arm signal pass through the light that sensing probe (3) and reference probe (4) returned afterwards respectively and carry out demodulation through first demodulation module (501) and second demodulation module (502) respectively; Carry out the decorrelation computing to remove same source noise by de-correlation modules (6) then, obtain exporting signal.
5. want 4 described methods like right, it is characterized in that,
Separate timing among the step S2, used demodulation method is digital arc tangent demodulation method, and the sensing path signal that obtains after the demodulation and the demodulation result of reference arm signal are respectively:
Wherein,
Be the phase information of sensing path signal,
Being the noise of sensing path signal, is phase noise
Light intensity noise n
i, circuit noise
Parameter in said system
C
sUnder pass through digitizing arc tangent demodulation result;
Be the phase information of reference arm signal,
Being the reference arm noise, is phase noise
Light intensity noise n
i, circuit noise
Parameter in said system
C
rUnder pass through digitizing arc tangent demodulation result;
Be the output of additivity light intensity noise in the demodulation result.
6. method as claimed in claim 5 is characterized in that, to carry out the step of computing following for de-correlation modules among the step S2:
The two-way of 3x2 coupling mechanism output signal is carried out linear combination obtains composite signal i, make the information that comprises the phase place
of sensing path signal in the phase place of composite signal:
Wherein, i
R1Be the first via of the two-way output signal of 3x2 coupling mechanism, i
R2Be the second the tunnel, K is the splitting ratio of coupling mechanism;
Then said composite signal i is carried out demodulation, obtains phase value and be:
Wherein,
Wherein
Be a fixing phase differential of the two-way output signal of 3 * 2 coupling mechanisms, because C
r≈ C
sSo, have:
7. method as claimed in claim 6 is characterized in that, the signal that carries out among the step S2 exporting after the decorrelation computing is following:
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201110191719.4A CN102359797B (en) | 2011-07-08 | 2011-07-08 | System and method for reducing noise of phase generated carrier (PGC) system in optical fiber hydrophone |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201110191719.4A CN102359797B (en) | 2011-07-08 | 2011-07-08 | System and method for reducing noise of phase generated carrier (PGC) system in optical fiber hydrophone |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN102359797A true CN102359797A (en) | 2012-02-22 |
| CN102359797B CN102359797B (en) | 2014-05-07 |
Family
ID=45585160
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201110191719.4A Expired - Fee Related CN102359797B (en) | 2011-07-08 | 2011-07-08 | System and method for reducing noise of phase generated carrier (PGC) system in optical fiber hydrophone |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN102359797B (en) |
Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103115633A (en) * | 2013-01-29 | 2013-05-22 | 复旦大学 | Method for reducing scattered (reflected) light interference on interference path by aid of phase generated carrier |
| CN105067017A (en) * | 2015-06-02 | 2015-11-18 | 哈尔滨工程大学 | Modified phase generated carrier (PGC) demodulation method |
| CN105486331A (en) * | 2015-12-01 | 2016-04-13 | 哈尔滨工程大学 | High-precision optical signal phase demodulation system and demodulation method |
| CN106052843A (en) * | 2016-08-09 | 2016-10-26 | 北京航天控制仪器研究所 | Heterodyne-interference-type optical fiber hydrophone time division multiplexing array and demodulation method |
| CN106768269A (en) * | 2016-11-25 | 2017-05-31 | 威海北洋光电信息技术股份公司 | Fiber-optic hydrophone system based on PGC principles |
| CN107014478A (en) * | 2017-04-10 | 2017-08-04 | 中国人民解放军国防科学技术大学 | Modulation-demodulation device for optical fiber vector hydrophone |
| CN107677357A (en) * | 2017-08-18 | 2018-02-09 | 北京航天控制仪器研究所 | A kind of symmetrical expression bobbin-type fiber optic hydrophone unit of resisting temperature drift |
| CN109541697A (en) * | 2019-01-28 | 2019-03-29 | 上海太易检测技术有限公司 | A kind of metal detection system and method with noise suppression arrangement |
| CN109631962A (en) * | 2018-12-20 | 2019-04-16 | 中国人民解放军国防科技大学 | Multi-frequency carrier polarization modulation and demodulation system and method based on PGC scheme |
| CN109708743A (en) * | 2019-02-20 | 2019-05-03 | 湖北工业大学 | A kind of interference formula fibre optic hydrophone detection system |
| CN111044138A (en) * | 2019-12-26 | 2020-04-21 | 北京航天控制仪器研究所 | Time-division wavelength-division hybrid multiplexing array system of fiber laser hydrophone |
| CN109541697B (en) * | 2019-01-28 | 2024-06-11 | 上海太易检测技术有限公司 | Metal detection system and method with noise suppression structure |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5218418A (en) * | 1991-10-30 | 1993-06-08 | Layton Michael R | Differential fiber optic sensor and method |
| EP1985967B1 (en) * | 2007-04-26 | 2009-07-29 | Nxtar Technologies, Inc. | Fiber interferometric sensor and phase compensation method of PGC demodulator |
| CN101603857A (en) * | 2009-07-17 | 2009-12-16 | 哈尔滨工程大学 | Phase carrier demodulation method in the Fabry-Perot interference type fibre optic hydrophone |
| CN101608946A (en) * | 2009-06-23 | 2009-12-23 | 中国人民解放军海军工程大学 | Fiber laser hydrophone signal demodulating system |
-
2011
- 2011-07-08 CN CN201110191719.4A patent/CN102359797B/en not_active Expired - Fee Related
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5218418A (en) * | 1991-10-30 | 1993-06-08 | Layton Michael R | Differential fiber optic sensor and method |
| EP1985967B1 (en) * | 2007-04-26 | 2009-07-29 | Nxtar Technologies, Inc. | Fiber interferometric sensor and phase compensation method of PGC demodulator |
| CN101608946A (en) * | 2009-06-23 | 2009-12-23 | 中国人民解放军海军工程大学 | Fiber laser hydrophone signal demodulating system |
| CN101603857A (en) * | 2009-07-17 | 2009-12-16 | 哈尔滨工程大学 | Phase carrier demodulation method in the Fabry-Perot interference type fibre optic hydrophone |
Non-Patent Citations (3)
| Title |
|---|
| 吴艳群，等: "光纤矢量水听器系统本底噪声的自适应抵消", 《中国激光》 * |
| 张华勇，等: "光纤水听器时分复用系统通过3×3耦合器信号解调的一种新算法", 《中国激光》 * |
| 施清平，等: "一种消除伴生调幅的光源调频型相位生成载波调制方法", 《光电子激光》 * |
Cited By (17)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103115633B (en) * | 2013-01-29 | 2016-02-24 | 复旦大学 | Utilize phase generated carrier to reduce and interfere path loose (instead) to penetrate the method for light interference |
| CN103115633A (en) * | 2013-01-29 | 2013-05-22 | 复旦大学 | Method for reducing scattered (reflected) light interference on interference path by aid of phase generated carrier |
| CN105067017B (en) * | 2015-06-02 | 2017-11-28 | 哈尔滨工程大学 | A kind of improved generation carrier phase PGC demodulation methods |
| CN105067017A (en) * | 2015-06-02 | 2015-11-18 | 哈尔滨工程大学 | Modified phase generated carrier (PGC) demodulation method |
| CN105486331A (en) * | 2015-12-01 | 2016-04-13 | 哈尔滨工程大学 | High-precision optical signal phase demodulation system and demodulation method |
| CN106052843B (en) * | 2016-08-09 | 2019-10-18 | 北京航天控制仪器研究所 | A kind of heterodyne interference type fibre optic hydrophone time division multiplexing array and demodulation method |
| CN106052843A (en) * | 2016-08-09 | 2016-10-26 | 北京航天控制仪器研究所 | Heterodyne-interference-type optical fiber hydrophone time division multiplexing array and demodulation method |
| CN106768269A (en) * | 2016-11-25 | 2017-05-31 | 威海北洋光电信息技术股份公司 | Fiber-optic hydrophone system based on PGC principles |
| CN107014478A (en) * | 2017-04-10 | 2017-08-04 | 中国人民解放军国防科学技术大学 | Modulation-demodulation device for optical fiber vector hydrophone |
| CN107677357A (en) * | 2017-08-18 | 2018-02-09 | 北京航天控制仪器研究所 | A kind of symmetrical expression bobbin-type fiber optic hydrophone unit of resisting temperature drift |
| CN109631962A (en) * | 2018-12-20 | 2019-04-16 | 中国人民解放军国防科技大学 | Multi-frequency carrier polarization modulation and demodulation system and method based on PGC scheme |
| CN109631962B (en) * | 2018-12-20 | 2020-12-04 | 中国人民解放军国防科技大学 | Multi-frequency carrier polarization modulation and demodulation system and method based on PGC scheme |
| CN109541697A (en) * | 2019-01-28 | 2019-03-29 | 上海太易检测技术有限公司 | A kind of metal detection system and method with noise suppression arrangement |
| CN109541697B (en) * | 2019-01-28 | 2024-06-11 | 上海太易检测技术有限公司 | Metal detection system and method with noise suppression structure |
| CN109708743A (en) * | 2019-02-20 | 2019-05-03 | 湖北工业大学 | A kind of interference formula fibre optic hydrophone detection system |
| CN109708743B (en) * | 2019-02-20 | 2020-11-03 | 湖北工业大学 | Interference type optical fiber hydrophone detection system |
| CN111044138A (en) * | 2019-12-26 | 2020-04-21 | 北京航天控制仪器研究所 | Time-division wavelength-division hybrid multiplexing array system of fiber laser hydrophone |
Also Published As
| Publication number | Publication date |
|---|---|
| CN102359797B (en) | 2014-05-07 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN102359797B (en) | System and method for reducing noise of phase generated carrier (PGC) system in optical fiber hydrophone | |
| CN106052843B (en) | A kind of heterodyne interference type fibre optic hydrophone time division multiplexing array and demodulation method | |
| CN102680072B (en) | System and method for reducing noise of optical fiber hydrophone phase generated carrier (PGC) time division multiplexing system | |
| JP4844325B2 (en) | Optical fiber sensor system | |
| CN1067475C (en) | Optically encoded signals | |
| CN102461020A (en) | Method and device for transmitting optical information between an emitter station and receiving station via a multi-mode optical wave guide | |
| CN101216976A (en) | An optical fiber perimeter security-monitoring system and the corresponding implementation method based on phase generated carrier reusing | |
| CN109631962B (en) | Multi-frequency carrier polarization modulation and demodulation system and method based on PGC scheme | |
| CN106603158A (en) | High-precision distributed optical fiber frequency transfer method | |
| CN103575379A (en) | Random position point optical fiber distributed sonic sensor | |
| CN101506718A (en) | Mach-Zehnder light modulator, Mach-Zehnder light modulating method, light transmitter, light modulator, light transmitting apparatus, and light receiving apparatus | |
| CN110146155A (en) | A kind of Larger Dynamic range, highly sensitive fiber laser hydrophone system | |
| CN101771470B (en) | Method and device for receiving OPFDM-DQPSK signals | |
| CN106526301A (en) | Closed-loop independent double-sampling loop all-fiber current transformer based on single optical path | |
| CN103344264A (en) | Multichannel optical fiber sensing network demodulating system | |
| CN107171731B (en) | A kind of optical fiber eigen mode multiplexed communications method and system | |
| Cantono et al. | Optical network sensing: Opportunities and challenges | |
| CN109883460B (en) | Multiplexing device and method for multi-channel fiber interferometer based on pseudo-random code | |
| CN101945320B (en) | Distributed interference fiber-optic microphone array device based on space division multiplexing | |
| CN110160627A (en) | The optical fiber sound sensor system of Michelson interference and phase sensitive optical time domain reflection | |
| CN112539849B (en) | Quantum interference detection chip and test system thereof | |
| CN210780799U (en) | Hydrophone array optical relay remote transmission link loss monitoring device | |
| CN103595489B (en) | A kind of intercom system under water based on optical fiber sensing technology | |
| CN209844962U (en) | Long-distance high-precision optical fiber interference sensing positioning system | |
| CN102419186B (en) | Optical fiber sensing multiplexing method based on phase carrier multiplexing and system for realizing same |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20140507 Termination date: 20160708 |
|
| CF01 | Termination of patent right due to non-payment of annual fee |