CN210780799U - Hydrophone array optical relay remote transmission link loss monitoring device - Google Patents
Hydrophone array optical relay remote transmission link loss monitoring device Download PDFInfo
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- CN210780799U CN210780799U CN201921493699.4U CN201921493699U CN210780799U CN 210780799 U CN210780799 U CN 210780799U CN 201921493699 U CN201921493699 U CN 201921493699U CN 210780799 U CN210780799 U CN 210780799U
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Abstract
The utility model discloses a hydrophone array optical relay remote transmission link loss monitoring devices mainly includes narrow linewidth polarization maintaining light source, single side band polarization maintaining modulator, radio frequency signal source, polarization maintaining coupler, modulator, pulsed signal source, continuous basement light source, first single mode coupler, amplifier, polarization disturbing ware, second single mode coupler, isolator, third single mode coupler, balanced detector, data collection station, wavelength division multiplexer. The utility model discloses a mode such as probe light pulse, single sideband modulation probing light, sensing wavelength frequency selection add wavelength division multiplex are filled to continuous basement, have solved channel crosstalk, coupler noise, light surge, the slow scheduling problem of coherent fading noise convergence that optical fiber hydrophone array optical relay remote transmission link loss monitoring exists, are applied to bank base extension optical relay remote transmission link loss monitoring at present, realize 150km loss monitoring, possess better engineering application.
Description
Technical Field
The utility model relates to an optical fiber sensing's field, concretely relates to hydrophone array optical relay remote transmission link loss monitoring devices.
Background
The optical fiber hydrophone array can be used for monitoring and capturing the noise of the marine environment sound emission source and has the advantages of high sensitivity, strong phase detection capability, large dynamic range and the like. In order to detect the far-sea acoustic signals, the connection between the optical transceiver and the hydrophone array needs to be realized through an optical relay remote transmission link. The detection capability of the optical fiber hydrophone array is seriously influenced by the transmission loss of the optical relay remote transmission link and the defects of the optical cable. The method has important significance for loss monitoring of the hydrophone array optical relay remote transmission link.
In the field of communications, Coherent Optical Time Domain Reflectometry (COTDR) is widely applied to monitoring loss of submarine communication optical cables, and compared with the Coherent Optical Time Domain Reflectometry (COTDR), the main problems faced by the optical fiber hydrophone array optical relay remote transmission link include:
coupler noise: to detect the relay link performance, the undersea optical communication cable typically connects the uplink and downlink through a coupler. For the optical relay remote transmission link of the optical fiber hydrophone array, noise is introduced into the connection couplers of an uplink and a downlink, and the fidelity of acoustic signal detection is influenced;
channel crosstalk: the wavelength channel of the loss monitoring device may also cause crosstalk to the acoustic signal detection channel, affecting the detection performance of the hydrophone array;
optical surge: the power of the optical pulse with the low COTDR duty ratio can be increased once when the optical pulse passes through one repeater, so that optical surge is formed, the damage of the repeater is caused, and the healthy operation of a relay transmission link is influenced. In the prior art, filling light pulses and detection light pulses are introduced to synthesize quasi-continuous light (FSK + ASK), so that the problems of complex structure, high circuit control requirement and the like exist, and crosstalk noise can be introduced into the wavelength of the filling light pulses;
coherent fading noise converges slowly: if the optical fiber is not disturbed externally, the fluctuation caused by coherent fading noise is stable random fluctuation and can not be eliminated by accumulation average. In the prior art, frequency division multiplexing is introduced, but modulated multi-frequency sidebands easily cause channel crosstalk for hydrophone array remote transmission.
SUMMERY OF THE UTILITY MODEL
An object of the utility model is to overcome the not enough of prior art existence, and provide a hydrophone array optical relay remote transmission link loss monitoring devices.
The purpose of the utility model is accomplished through following technical scheme: the hydrophone array optical relay remote transmission link loss monitoring device mainly comprises a narrow linewidth polarization-maintaining light source, a single-side band polarization-maintaining modulator, a radio frequency signal source, a polarization-maintaining coupler, a modulator, a pulse signal source, a continuous substrate light source, a first single-mode coupler, an amplifier, a polarization scrambler, a second single-mode coupler, an isolator, a third single-mode coupler, a balance detector, a data collector and a wavelength division multiplexer, wherein the narrow linewidth polarization-maintaining light source is provided with a polarization-maintaining light output, the single-side band polarization-maintaining modulator is provided with a polarization-maintaining light input, a polarization-maintaining light output and an electrical input, the optical input of the single-side band polarization-maintaining modulator is connected with the optical output of the narrow linewidth polarization-maintaining light source, the radio frequency signal source is provided with an electrical output connected with the electrical input of the single-side band polarization-maintaining modulator, the polarization-maintaining coupler is provided with a polarization-maintaining light input and two polarization-maintaining light outputs, the optical input of the polarization-maintaining coupler is connected with, the modulator is provided with an optical input, an optical output and an electrical input, the optical input of the modulator is connected with one optical output of the polarization-maintaining coupler, the pulse signal source is provided with an electrical output connected with the electrical input of the modulator, the continuous base light source is provided with an optical output, the first single-mode coupler is provided with two optical inputs and one optical output, one optical input of the first single-mode coupler is connected with the optical output of the modulator, the other optical input is connected with the optical output of the continuous base light source, the amplifier is provided with an optical input and an optical output, the optical input of the amplifier is connected with the optical output of the first single-mode coupler, the polarization scrambler is provided with an optical input and an optical output, the optical input of the polarization scrambler is connected with the optical output of the amplifier, the second single-mode coupler and the third single-mode coupler are respectively provided with two optical inputs and two optical outputs, one optical input of the second single-mode coupler is connected with the optical output of the polarization scrambler, the other path of optical output enters a hydrophone array optical relay remote transmission downlink, the isolator is provided with an optical input and an optical output, the optical input of the isolator is connected with the output light of the hydrophone array optical relay remote transmission uplink, the optical output of the isolator is connected with the other path of optical input of the second single-mode coupler, the other path of optical output of the second single-mode coupler is connected with one path of optical input of the third single-mode coupler, the other path of optical input of the third single-mode coupler is connected with the other path of optical output of the polarization maintaining coupler, the balance detector is provided with two optical inputs and one electrical output, the two optical inputs of the balance detector are connected with the two paths of optical outputs of the third single-mode coupler, the data collector is provided with one path of electrical input which is connected with the electrical output of the balance detector, and the wavelength division multiplexer is arranged in the hydrophone array optical relay remote transmission link and is connected with a downlink and an uplink.
The narrow-linewidth polarization-maintaining light source outputs polarization-maintaining light with linewidth less than kHz, and the wavelength is selected on the principle that an acoustic detection channel is not occupied.
The single-side-band polarization-maintaining modulator is combined with a radio frequency signal source to carry out frequency shift on the light frequency of the narrow-linewidth polarization-maintaining light source, single-frequency and adjustable continuous light is generated, and quick traversal of coherent fluctuation noise is achieved.
The radio frequency signal source generates a radio frequency sinusoidal signal with adjustable 200MHz range.
The wavelength of the wavelength division multiplexer is selected based on the principle that the wavelength of the wavelength division multiplexer can be transmitted by sound detection wavelength and narrow line width polarization-maintaining light source wavelength, but the wavelength of the wavelength division multiplexer cannot be transmitted by continuous substrate light source wavelength.
The continuous light signal with the line width of 1 MHz-100 MHz is output by the continuous substrate light source and is used as substrate filling light, and the wavelength is selected according to the principle that the continuous light signal does not occupy an acoustic detection channel and can be filtered by a wavelength division multiplexer.
The utility model has the advantages that: the utility model adopts the continuous substrate filling detection light pulse, saves the steps of time delay alignment between pulses, signal conditioning and the like, and reduces the complexity of the system and the difficulty of hardware realization; by reasonably selecting the wavelength of the continuous substrate light source, filling light generated by the continuous substrate light source is filtered by a wavelength division multiplexer in the hydrophone array optical relay remote transmission link, so that channel crosstalk is reduced; by reasonably selecting the wavelength of the narrow-linewidth light source and adopting the single-side band modulator to generate the narrow-linewidth light with single frequency and adjustable frequency in a small range, the channel crosstalk is not caused, the traversal of coherent fluctuation noise can be realized, and the loss test efficiency is improved; a wavelength division multiplexer is adopted in the hydrophone array optical relay remote transmission link to replace a coupler to connect an uplink and a downlink, so that the degradation of the acoustic detection performance of the hydrophone by a loss test link is avoided.
Drawings
Fig. 1 is a schematic structural diagram of the present invention.
Description of reference numerals: the device comprises a narrow-linewidth polarization-maintaining light source 101, a single-side band polarization-maintaining modulator 102, a radio frequency signal source 103, a polarization-maintaining coupler 104, a modulator 105, a pulse signal source 106, a continuous-substrate light source 107, a first single-mode coupler 108, an amplifier 109, a polarization scrambler 110, a second single-mode coupler 111, an isolator 112, a third single-mode coupler 113, a balanced detector 114 and a data acquisition unit 115.
Detailed Description
The present invention will be described in detail with reference to the accompanying drawings:
example (b): as shown in the attached drawing, the loss monitoring device of the hydrophone array optical relay remote transmission link mainly comprises a narrow-linewidth polarization-maintaining light source 101, a single-sideband polarization-maintaining modulator 102, a radio frequency signal source 103, a polarization-maintaining coupler 104, a modulator 105, a pulse signal source 106, a continuous substrate light source 107, a first single-mode coupler 108, an amplifier 109, a polarization scrambler 110, a second single-mode coupler 111, an isolator 112, a third single-mode coupler 113, a balance detector 114, a data collector 115 and a wavelength division multiplexer, wherein the narrow-linewidth polarization-maintaining light source 101 has a polarization-maintaining light output, the single-sideband polarization-maintaining modulator 102 has a polarization-maintaining light input, a polarization-maintaining light output and an electrical input, the optical input of the single-linewidth polarization-maintaining modulator 102 is connected with the optical output of the narrow-linewidth polarization-maintaining light source 101, the radio frequency signal source 103 is provided with an electrical output connected with the electrical input of the single-linewidth polarization, the polarization maintaining coupler 104 is provided with a polarization maintaining light input and two polarization maintaining light outputs, and the radio frequency signal source 103 is used for generating a radio frequency sinusoidal signal with adjustable 200MHz range. The optical input of the polarization-maintaining coupler 104 is connected with the optical output of the single-sideband polarization-maintaining modulator 102, the modulator 105 is provided with an optical input, an optical output and an electrical input, the optical input of the modulator 105 is connected with one path of optical output of the polarization-maintaining coupler 104, the pulse signal source 106 is provided with one electrical output which is connected with the electrical input of the modulator 105, the single-frequency light output by the single-sideband polarization-maintaining modulator 102 is divided into two paths by the polarization-maintaining coupler 104, 1% of the output is used as reference light, and 99% of the output enters the modulator 105. The modulator 105 may select an acoustic-optical modulator or an electro-optical modulator. The pulse signal source 106 is used for modulating the continuous light signal of the modulator 105 to generate a probe light pulse with a certain period and duty cycle. The continuous base light source 107 is provided with an optical output, the first single mode coupler 108 has two optical inputs and an optical output, one optical input of the first single mode coupler 108 is connected to the optical output of the modulator 105, the other optical input is connected to the optical output of the continuous base light source 107, the amplifier 109 is provided with an optical input and an optical output, the optical input of the amplifier 109 is connected to the optical output of the first single mode coupler 108, the polarization scrambler 110 is provided with an optical input and an optical output, the optical input of the polarization scrambler 110 is connected to the optical output of the amplifier 109, the second single mode coupler 111 and the third single mode coupler 113 each have two optical inputs and two optical outputs, one optical input of the second single mode coupler 111 is connected to the optical output of the polarization scrambler 110, the other optical output enters the hydrophone array optical relay remote transmission downlink, the sequence of probe optical pulses with continuous base generates rayleigh scattered light in the hydrophone array optical relay remote transmission link, back into the second single mode coupler 111 via the uplink. To avoid channel crosstalk, an isolator 112 may be interposed for optical path direction isolation. The isolator 112 is provided with an optical input and an optical output, the optical input of the isolator 112 is connected with the output light of the optical relay remote transmission uplink of the hydrophone array, the optical output of the isolator 112 is connected with the other optical input of the second single-mode coupler 111, the other optical output of the second single-mode coupler 111 is connected with one optical input of the third single-mode coupler 113, the other optical input of the third single-mode coupler 113 is connected with the other optical output of the polarization maintaining coupler 104, the balanced detector 114 has two optical inputs and one electrical output, the two optical inputs of the balanced detector 114 are connected with the two optical outputs of the third single-mode coupler 113, the data collector 115 is provided with one electrical input to be connected with the electrical output of the balanced detector 114, and the wavelength division multiplexer is arranged in the optical relay remote transmission link of the hydrophone array to connect the downlink and the uplink. The rayleigh scattered light signal carries loss distribution information of the hydrophone array optical relay remote transmission downlink, passes through the output end of the second single-mode coupler 111 to serve as signal light, enters the third single-mode coupler 113 to be combined with 1% of reference light of the polarization maintaining coupler 104, is subjected to balanced detection through the balanced detector 114, outputs an electric signal which only contains alternating current components and contains loss distribution information, and is collected and quantized through the data collector 115 to obtain loss distribution of the hydrophone array optical relay remote transmission downlink.
The narrow linewidth polarization-maintaining light source 101 outputs polarization-maintaining light with linewidth less than 5kHz, and the wavelength is selected on the principle that an acoustic detection channel is not occupied. If the sounding channel is in ITU C30, the wavelength of the narrow linewidth polarization maintaining light source 101 can be selected to be in C22. The single-sideband polarization-maintaining modulator 102 and the radio frequency signal source 103 are combined to shift the frequency of the light of the narrow-linewidth polarization-maintaining light source 101 to generate single-frequency and adjustable continuous light, so that the rapid traversal of coherent fluctuation noise is realized, and the loss monitoring result is rapidly collected. The single sideband polarization maintaining modulator 102 can be realized by selecting a double parallel IQ electro-optic modulator and a 90-degree bridge. The wavelength of the wavelength division multiplexer is selected to be transparent to the acoustic detection wavelength and the narrow linewidth polarization maintaining light source 101 wavelength, but not to the continuous substrate light source 107 wavelength. The wavelength division multiplexer is used for separating the acoustic detection wavelength and the loss monitoring wavelength. In this example, the wavelength division multiplexer of C22/C30 is selected. The continuous substrate light source 107 outputs a continuous optical signal with a line width of 1MHz to 100MHz as substrate filling light, and the wavelength is selected on the principle that the continuous optical signal does not occupy an acoustic detection channel and can be filtered by a wavelength division multiplexer. The C58 channel may be selected in this example. The continuous substrate filling light output by the continuous substrate light source 107 and the probe light pulse sequence output by the modulator 105 are multiplexed by the first single-mode coupler 108 to form a probe light pulse sequence with a continuous substrate, and the probe light pulse sequence is subjected to power boosting by the amplifier 109, subjected to polarization traversal by the polarization scrambler 110, and input into the hydrophone array optical relay remote transmission downlink through the second single-mode coupler 111.
The utility model discloses a detection light pulse is filled to continuous basement, single sideband modulation probing light, sensing wavelength frequency selection adds modes such as wavelength division multiplexing, the channel crosstalk who has solved the long-range transmission link loss monitoring of optic fibre hydrophone array optical relay existence, the coupler noise, the light surge, coherent fading noise convergence slow scheduling problem, for optic fibre hydrophone array optical relay long-range transmission link loss monitoring provides effectual solution, be applied to bank base extension optical relay long-range transmission link loss monitoring at present, realize 150km loss monitoring, possess better engineering application.
It should be understood that equivalent substitutions or changes to the technical solution and the inventive concept of the present invention should be considered to fall within the scope of the appended claims for the skilled person.
Claims (6)
1. A hydrophone array optical relay remote transmission link loss monitoring device is characterized in that: mainly comprises a narrow linewidth polarization-maintaining light source (101), a single-side polarization-maintaining modulator (102), a radio frequency signal source (103), a polarization-maintaining coupler (104), a modulator (105), a pulse signal source (106), a continuous substrate light source (107), a first single-mode coupler (108), an amplifier (109), a polarization scrambler (110), a second single-mode coupler (111), an isolator (112), a third single-mode coupler (113), a balance detector (114), a data collector (115) and a wavelength division multiplexer, wherein the narrow linewidth polarization-maintaining light source (101) is provided with a polarization-maintaining light output, the single-side polarization-maintaining modulator (102) is provided with a polarization-maintaining light input, a polarization-maintaining light output and an electrical input, the optical input of the single-side polarization-maintaining light source (102) is connected with the optical output of the narrow polarization-maintaining light source (101), the radio frequency signal source (103) is provided with an electrical output connected with the electrical input of the single-side polarization-maintaining modulator (102, the polarization maintaining coupler (104) is provided with a polarization maintaining light input and two polarization maintaining light outputs, the light input of the polarization maintaining coupler (104) is connected with the light output of the single-side band polarization maintaining modulator (102), the modulator (105) is provided with a light input, a light output and an electric input, the light input of the modulator (105) is connected with one light output of the polarization maintaining coupler (104), the pulse signal source (106) is provided with an electric output which is connected with the electric input of the modulator (105), the continuous substrate light source (107) is provided with a light output, the first single mode coupler (108) is provided with two light inputs and one light output, one light input of the first single mode coupler (108) is connected with the light output of the modulator (105), the other light input is connected with the light output of the continuous substrate light source (107), the amplifier (109) is provided with one light input and one light output, the light input of the amplifier (109) is connected with the light output of the first single mode coupler (108), the polarization scrambler (110) is provided with an optical input and an optical output, the optical input of the polarization scrambler (110) is connected with the optical output of the amplifier (109), the second single-mode coupler (111) and the third single-mode coupler (113) are respectively provided with two optical inputs and two optical outputs, one path of optical input of the second single-mode coupler (111) is connected with the optical output of the polarization scrambler (110), the other path of optical output enters a hydrophone array optical relay remote transmission downlink, the isolator (112) is provided with an optical input and an optical output, the optical input of the isolator (112) is connected with the optical relay remote transmission uplink output of the hydrophone array, the optical output of the isolator (112) is connected with the other path of optical input of the second single-mode coupler (111), the other path of optical output of the second single-mode coupler (111) is connected with one path of optical input of the third single-mode coupler (113), the other optical input of the third single-mode coupler (113) is connected with the other optical output of the polarization-maintaining coupler (104), the balance detector (114) is provided with two optical inputs and one electrical output, the two optical inputs of the balance detector (114) are connected with the two optical outputs of the third single-mode coupler (113), the data acquisition unit (115) is provided with one electrical input connected with the electrical output of the balance detector (114), and the wavelength division multiplexer is arranged in the hydrophone array optical relay remote transmission link and connected with a downlink and an uplink.
2. The hydrophone array optical relay remote transmission link loss monitoring device of claim 1, wherein: the narrow-linewidth polarization-maintaining light source (101) outputs polarization-maintaining light with linewidth less than 5kHz, and the wavelength is selected on the principle that an acoustic detection channel is not occupied.
3. The hydrophone array optical relay remote transmission link loss monitoring device of claim 1, wherein: the single-side band polarization-maintaining modulator (102) and the radio frequency signal source (103) are combined to carry out frequency shift on the light frequency of the narrow-linewidth polarization-maintaining light source (101) to generate single-frequency and adjustable continuous light, and the rapid traversal of coherent fluctuation noise is realized.
4. The hydrophone array optical relay remote transmission link loss monitoring device of claim 1, wherein: the radio frequency signal source (103) generates a radio frequency sinusoidal signal with adjustable 200MHz range.
5. The hydrophone array optical relay remote transmission link loss monitoring device of claim 1, wherein: the wavelength of the wavelength division multiplexer is selected on the basis that the wavelength of the wavelength division multiplexer can be transmitted by the sound detection wavelength and the wavelength of the narrow linewidth polarization-maintaining light source (101) but can not be transmitted by the continuous substrate light source (107).
6. The hydrophone array optical relay remote transmission link loss monitoring device of claim 1, wherein: the continuous substrate light source (107) outputs a continuous optical signal with the line width of 1 MHz-100 MHz as substrate filling light, and the wavelength is selected according to the principle that the continuous optical signal does not occupy an acoustic detection channel and can be filtered by a wavelength division multiplexer.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110868251A (en) * | 2019-09-10 | 2020-03-06 | 中国船舶重工集团公司第七一五研究所 | Hydrophone array optical relay remote transmission link loss monitoring device |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN110868251A (en) * | 2019-09-10 | 2020-03-06 | 中国船舶重工集团公司第七一五研究所 | Hydrophone array optical relay remote transmission link loss monitoring device |
| CN110868251B (en) * | 2019-09-10 | 2024-07-05 | 中国船舶重工集团公司第七一五研究所 | Hydrophone array optical relay remote transmission link loss monitoring device |
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