CN113972950A - Optical fiber link dispersion measurement system and method based on time division multiplexing - Google Patents
Optical fiber link dispersion measurement system and method based on time division multiplexing Download PDFInfo
- Publication number
- CN113972950A CN113972950A CN202111112771.6A CN202111112771A CN113972950A CN 113972950 A CN113972950 A CN 113972950A CN 202111112771 A CN202111112771 A CN 202111112771A CN 113972950 A CN113972950 A CN 113972950A
- Authority
- CN
- China
- Prior art keywords
- signal
- optical fiber
- sub
- optical
- fiber link
- 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.)
- Pending
Links
- 239000013307 optical fiber Substances 0.000 title claims abstract description 107
- 239000006185 dispersion Substances 0.000 title claims abstract description 88
- 238000000034 method Methods 0.000 title claims abstract description 25
- 238000005259 measurement Methods 0.000 title claims description 45
- 230000003287 optical effect Effects 0.000 claims abstract description 109
- 230000007274 generation of a signal involved in cell-cell signaling Effects 0.000 claims description 22
- 239000000835 fiber Substances 0.000 claims description 5
- 230000005540 biological transmission Effects 0.000 abstract description 9
- 230000009286 beneficial effect Effects 0.000 abstract description 3
- 238000010586 diagram Methods 0.000 description 10
- 238000001514 detection method Methods 0.000 description 7
- 238000005516 engineering process Methods 0.000 description 3
- 238000012545 processing Methods 0.000 description 3
- 238000004891 communication Methods 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 238000000691 measurement method Methods 0.000 description 2
- 230000001419 dependent effect Effects 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 230000008676 import Effects 0.000 description 1
- GQYHUHYESMUTHG-UHFFFAOYSA-N lithium niobate Chemical compound [Li+].[O-][Nb](=O)=O GQYHUHYESMUTHG-UHFFFAOYSA-N 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000012552 review Methods 0.000 description 1
- 230000035945 sensitivity Effects 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 230000026676 system process Effects 0.000 description 1
- 238000012546 transfer Methods 0.000 description 1
Images
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B10/00—Transmission systems employing electromagnetic waves other than radio-waves, e.g. infrared, visible or ultraviolet light, or employing corpuscular radiation, e.g. quantum communication
- H04B10/07—Arrangements for monitoring or testing transmission systems; Arrangements for fault measurement of transmission systems
- H04B10/075—Arrangements for monitoring or testing transmission systems; Arrangements for fault measurement of transmission systems using an in-service signal
- H04B10/079—Arrangements for monitoring or testing transmission systems; Arrangements for fault measurement of transmission systems using an in-service signal using measurements of the data signal
- H04B10/0795—Performance monitoring; Measurement of transmission parameters
- H04B10/07951—Monitoring or measuring chromatic dispersion or PMD
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04J—MULTIPLEX COMMUNICATION
- H04J14/00—Optical multiplex systems
- H04J14/08—Time-division multiplex systems
Landscapes
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Optical Communication System (AREA)
Abstract
The invention discloses a system and a method for measuring optical fiber link dispersion based on time division multiplexing, wherein a first optical signal and a second optical signal are transmitted to a modulation module in a time-sharing manner, a third signal with preset frequency is used for respectively modulating the first optical signal and the second optical signal, the first optical signal and the second optical signal are transmitted through an optical fiber link and then demodulated, the demodulated first sub-signal and the demodulated second sub-signal are subjected to frequency mixing and phase discrimination with the preset frequency, so that a first phase difference of the third signal and the demodulated first signal and a second phase difference of the third signal and the demodulated second signal are determined, and a dispersion coefficient is determined according to the wavelength of the first optical signal, the wavelength of the second optical signal, the first phase difference, the second phase difference and the length of the optical fiber link. The invention can accurately measure the dispersion coefficient of the optical fiber link, provides support for subsequent dispersion compensation, greatly improves the accuracy of optical fiber time transmission, can reduce the cost and is beneficial to application in practical engineering.
Description
Technical Field
The invention belongs to the technical field of optical fiber time service, and particularly relates to a system and a method for measuring optical fiber link dispersion based on time division multiplexing.
Background
The high-precision optical fiber time frequency transmission technology has the advantages of safety, reliability, stability and the like, and becomes a key supporting technology in the fields of aerospace, high-speed communication, geodetic surveying, precision metering and the like.
In practical applications of fiber time frequency transfer, dispersion is one of the losses of fiber transmission. The optical fiber dispersion is mainly caused by the fact that signals transmitted by the optical fiber dispersion are carried by different frequency components and different mode components, and the transmission speeds of the different frequency components and the different mode components are different, so that the signals are distorted. The dispersion not only causes interference to the transmission code, so that the error rate performance is deteriorated, the information transmission is seriously influenced, but also causes the broadening of the optical pulse, and the transmission capacity of the optical fiber is limited. With the increasing manufacturing process of optical fiber, the transmission distance of optical communication system is no longer limited by the loss of optical fiber, and the dispersion becomes the main limiting factor.
In the process of performing dispersion compensation, accurate dispersion measurement needs to be performed first. The cost is extremely high due to the purchase of expensive import equipment, and the method is not consistent with the scenes of wide application of optical fiber time transmission and is difficult to popularize and apply. Therefore, it is highly desirable to develop a reliable and low-cost method for measuring the dispersion of an optical fiber.
Disclosure of Invention
In order to solve the above problems in the prior art, the present invention provides a system and a method for measuring chromatic dispersion of an optical fiber link based on time division multiplexing. The technical problem to be solved by the invention is realized by the following technical scheme:
in a first aspect, the present invention provides a time division multiplexing-based optical fiber link dispersion measurement system, which includes a first signal generation module, a second signal generation module, a modulation module, a demodulation module, a phase discriminator, and a measurement module; wherein,
the first signal generation module is used for generating a first optical signal;
the second signal generation module is used for generating a second optical signal;
the modulation module is configured to modulate the first optical signal and the second optical signal respectively by using a third signal with a preset frequency to obtain a first sub-signal and a second sub-signal, and transmit the first sub-signal and the second sub-signal to the demodulation module by using an optical fiber link;
the demodulation module is used for demodulating the first sub-signal and the second sub-signal and transmitting the demodulated first sub-signal and the demodulated second sub-signal to the phase discriminator;
the phase discriminator is used for determining a first phase difference according to the third signal and the demodulated first sub-signal, and determining a second phase difference according to the third signal and the demodulated second sub-signal;
the measurement module is configured to determine a dispersion coefficient according to the first phase difference, the second phase difference, the wavelength of the first optical signal, the wavelength of the second optical signal, and the length of the optical fiber link.
In one embodiment of the invention, the first signal generating module and the second signal generating module comprise lasers.
In one embodiment of the invention, the modulation module comprises a voltage-controlled oscillator and a fiber intensity modulator connected with the voltage-controlled oscillator;
the voltage-controlled oscillator is used for generating a third signal with preset frequency and sending the third signal to the optical fiber intensity modulator;
the optical fiber intensity modulator is configured to modulate the first optical signal and the second optical signal with the third signal, respectively.
In one embodiment of the invention, the demodulation module comprises at least an avalanche photodetector.
In one embodiment of the present invention, the apparatus further comprises a switch module, and the switch module is configured to connect the first signal generation module or the second signal generation module to the modulation module in a time division multiplexing manner according to an instruction.
In a second aspect, the present invention further provides a method for measuring chromatic dispersion of an optical fiber link based on time division multiplexing, which is applied to any one of the systems for measuring chromatic dispersion of an optical fiber link based on time division multiplexing in the first aspect;
the method comprises the following steps:
receiving a first optical signal, and modulating the first optical signal by using a third signal with a preset frequency to obtain a first sub-signal;
after the first sub-signal is transmitted by using an optical fiber link, demodulating the first sub-signal;
determining a first phase difference according to the third signal and the demodulated first sub-signal;
receiving a second optical signal, and modulating the second optical signal by using a third signal with a preset frequency to obtain a second sub-signal;
after the second sub-signal is transmitted by using an optical fiber link, demodulating the second sub-signal;
determining a second phase difference according to the third signal and the demodulated second sub-signal;
and determining the dispersion coefficient according to the wavelength of the first optical signal, the wavelength of the second optical signal, the first phase difference, the second phase difference and the length of the optical fiber link.
In one embodiment of the present invention, the frequency of the demodulated first sub-signal and the frequency of the demodulated second sub-signal are equal to the preset frequency of the third signal.
In an embodiment of the present invention, the step of determining the dispersion coefficient according to the wavelength of the first optical signal, the wavelength of the second optical signal, the first phase difference, the second phase difference, and the length of the optical fiber link includes:
determining a difference value between the first phase difference and the second phase difference to obtain a first difference value;
determining the difference between the wavelength of the first optical signal and the wavelength of the second optical signal to obtain a second difference value;
determining a dispersion measurement value according to the first difference value and the second difference value;
and determining the dispersion coefficient according to the dispersion measured value and the length of the optical fiber link.
In one embodiment of the present invention, the dispersion coefficient is determined according to the following equation:
wherein L represents the length of the optical fiber link, DLRepresents the dispersion measurement, D represents the dispersion coefficient, wherein,
representing a first difference and a lambda representing a second difference.
In one embodiment of the invention, the length of the optical fiber link is 10km to 250 km.
Compared with the prior art, the invention has the beneficial effects that:
the invention provides a system and a method for measuring optical fiber link dispersion based on time division multiplexing, wherein a first optical signal and a second optical signal are transmitted to a modulation module in a time-sharing mode, the first optical signal and the second optical signal are modulated by using a third signal with preset frequency, then the first optical signal and the second optical signal are demodulated after passing through an optical fiber link, and the demodulated first sub-signal and the demodulated second sub-signal are subjected to frequency mixing and phase discrimination with the preset frequency to obtain two paths of phase differences.
The present invention will be described in further detail with reference to the accompanying drawings and examples.
Drawings
Fig. 1 is a schematic structural diagram of a time division multiplexing-based optical fiber link dispersion measurement system according to an embodiment of the present invention;
FIG. 2 is a schematic diagram of another structure of a dispersion measurement system for a time-division-multiplexing-based optical fiber link according to an embodiment of the present invention;
FIG. 3 is a schematic diagram of another structure of a dispersion measurement system for a time-division-multiplexing-based optical fiber link according to an embodiment of the present invention;
FIG. 4 is a schematic diagram of another structure of a dispersion measurement system for a time-division-multiplexing-based optical fiber link according to an embodiment of the present invention;
FIG. 5 is a schematic diagram of another structure of a dispersion measurement system for a time-division-multiplexing-based optical fiber link according to an embodiment of the present invention;
fig. 6 is a schematic flowchart of a method for measuring chromatic dispersion of an optical fiber link based on time division multiplexing according to an embodiment of the present invention.
Detailed Description
The present invention will be described in further detail with reference to specific examples, but the embodiments of the present invention are not limited thereto.
Fig. 1 is a schematic structural diagram of a time division multiplexing-based optical fiber link dispersion measurement system according to an embodiment of the present invention. As shown in fig. 1, an embodiment of the present invention provides a time division multiplexing-based optical fiber link dispersion measurement system 100, which includes a first signal generation module 10, a second signal generation module 20, a modulation module 30, a demodulation module 40, a phase detector 50, and a measurement module 60; wherein,
the first signal generation module 10 is used for generating a first optical signal;
the second signal generation module 20 is configured to generate a second optical signal;
the modulation module 30 is configured to modulate the first optical signal and the second optical signal respectively by using a third signal with a preset frequency to obtain a first sub-signal and a second sub-signal, and transmit the first sub-signal and the second sub-signal to the demodulation module 40 by using an optical fiber link;
the demodulation module 40 is configured to demodulate the first sub-signal and the second sub-signal, and transmit the demodulated first sub-signal and the demodulated second sub-signal to the phase detector 50;
the phase discriminator 50 is configured to determine a first phase difference according to the third signal and the demodulated first sub-signal, and determine a second phase difference according to the third signal and the demodulated second sub-signal;
the measurement module 60 is configured to determine the dispersion coefficient according to the first phase difference, the second phase difference, the wavelength of the first optical signal, the wavelength of the second optical signal, and the length of the optical fiber link.
In this embodiment, the optical fiber link dispersion measurement system 100 based on time division multiplexing includes a first signal generation module 10, a second signal generation module 20, a modulation module 30, a demodulation module 40, a phase discriminator 50, and a measurement module 60; specifically, the first signal generating module 10 and the second signal generating module 20 include lasers, the first signal generating module 10 is configured to generate a first optical signal, and the second signal generating module 20 is configured to generate a second optical signal, where the first optical signal and the second optical signal have different wavelengths; illustratively, the wavelength λ of the first optical signal11546.92nm, wavelength λ of the second optical signal2＝1550.92nm。
Further, the modulation module 30 modulates the two paths of optical signals respectively by using a third signal with a preset frequency to obtain a first sub-signal and a second sub-signal, and transmits the first sub-signal and the second sub-signal to the demodulation module 40 by using an optical fiber link, the demodulation module 40 demodulates the first sub-signal and the second sub-signal, and transmits the demodulated first sub-signal and the demodulated second sub-signal to the phase discriminator 50, the phase discriminator 50 performs phase difference measurement to determine a first phase difference between the third signal and the demodulated first sub-signal and a second phase difference between the third signal and the demodulated second sub-signal, and the measurement module 60 determines the dispersion coefficient of the optical fiber link according to the first phase difference, the second phase difference, the wavelength of the first optical signal, the wavelength of the second optical signal, and the length of the optical fiber link.
Of course, after the measurement module 60 determines the dispersion coefficient of the optical fiber link, the measurement result may be sent to the optical fiber timing system for timing. It should be noted that in this embodiment, the phase detector 50 is an analog phase detector formed by two D flip-flop 2G74 chips, and is used to complete a phase detection function.
Fig. 2 is a schematic structural diagram of an optical fiber link dispersion measurement system based on time division multiplexing according to an embodiment of the present invention. Optionally, referring to fig. 2, the modulation module 30 includes a voltage-controlled oscillator 301, and an optical fiber intensity modulator 302 connected to the voltage-controlled oscillator 301;
the voltage-controlled oscillator 301 is configured to generate a third signal with a preset frequency, and send the third signal to the optical fiber intensity modulator 302;
the fiber intensity modulator 302 is configured to modulate the first optical signal and the second optical signal with the third signal, respectively.
Specifically, in the optical fiber link dispersion measurement system 100 based on time division multiplexing, the modulation module 30 may include a voltage-controlled oscillator 301 and an optical fiber intensity modulator 302, and after the voltage-controlled oscillator 301 generates a third signal with a preset frequency, the third signal is sent to the optical fiber intensity modulator 302 to modulate the first optical signal and the second optical signal.
Optionally, the demodulation module 40 comprises at least an avalanche photodetector.
In this embodiment, the optical fiber intensity modulator 302 is a lithium niobate optical fiber intensity modulator, and the predetermined frequency of the third signal may be 100 MHz.
Fig. 3 is a schematic structural diagram of an optical fiber link dispersion measurement system based on time division multiplexing according to an embodiment of the present invention. Referring to fig. 1 and fig. 3, the above-mentioned optical fiber link dispersion measurement system 100 based on time division multiplexing further includes a switch module 70, where the switch module 70 is configured to connect the first signal generation module 10 or the second signal generation module 20 to the modulation module 30 in a time division multiplexing manner according to an instruction; that is, the above-described system processes the first optical signal when the switching module 70 connects the first signal generating module 10 to the modulation module 30 (as shown in fig. 1), and processes the second optical signal when the switching module 70 connects the second signal generating module 20 to the modulation module 30 (as shown in fig. 2).
Fig. 4 is a schematic structural diagram of an optical fiber link dispersion measurement system based on time division multiplexing according to an embodiment of the present invention. Optionally, referring to fig. 4, the above-mentioned optical fiber link dispersion measurement system 100 based on time division multiplexing further includes a control module 80, configured to detect whether the phase detector 50 determines the first phase difference according to the third signal and the demodulated first sub-signal; if yes, a command is sent to the switch module 70, so that the switch module 70 disconnects the first signal generating module 10 from the modulation module 30 and connects the second signal generating module 20 to the modulation module 30.
Fig. 5 is a schematic structural diagram of another optical fiber link dispersion measurement system based on time division multiplexing according to an embodiment of the present invention, where the optical fiber link dispersion measurement system 100 further includes a power detection module 90, and the demodulation module 40 may further include a first type of photodetector in addition to the avalanche type photodetector, where a detection range of the first type of photodetector is smaller than that of the avalanche type photodetector. Specifically, the power detection module 90 is configured to detect powers of a first sub-signal and a second sub-signal transmitted through the optical fiber link, and if the power of the first sub-signal or the power of the second sub-signal is less than-30 dbm, demodulate the first sub-signal or the second sub-signal by using an avalanche photodetector; and if the power of the first sub-signal or the second sub-signal is larger than-30 dbm, demodulating by using a first type of photoelectric detector with a smaller detection range.
Fig. 6 is a schematic flowchart of a method for measuring chromatic dispersion of an optical fiber link based on time division multiplexing according to an embodiment of the present invention. Referring to fig. 6, the present invention further provides a method for measuring chromatic dispersion of an optical fiber link based on time division multiplexing, which is applied to the system 100 for measuring chromatic dispersion of an optical fiber link based on time division multiplexing;
the method comprises the following steps:
s1, receiving the first optical signal, and modulating the first optical signal by using a third signal with a preset frequency to obtain a first sub-signal;
s2, after the first sub-signal is transmitted by using the optical fiber link, demodulating the first sub-signal;
s3, determining a first phase difference according to the third signal and the demodulated first sub-signal;
s4, receiving the second optical signal, and modulating the second optical signal by using a third signal with a preset frequency to obtain a second sub-signal;
s5, after the second sub-signal is transmitted by using the optical fiber link, demodulating the second sub-signal;
s6, determining a second phase difference according to the third signal and the demodulated second sub-signal;
and S7, determining the dispersion coefficient according to the wavelength of the first optical signal, the wavelength of the second optical signal, the first phase difference, the second phase difference and the length of the optical fiber link.
Specifically, first, a first optical signal is received, a third signal with a preset frequency is used for modulating the first optical signal to obtain a first sub-signal, the signal is transmitted and demodulated by using an optical fiber link, and a first phase difference can be determined according to the third signal and the demodulated first sub-signal. It should be understood that the second phase difference can be determined after the second optical signal is processed in the same way as the first optical signal, and thus the processing of the second optical signal will not be described herein.
It should be noted that the frequency of the demodulated first sub-signal and the frequency of the demodulated second sub-signal are both equal to the preset frequency of the third signal.
In addition, in the optical fiber link dispersion measurement method, the mechanical optical switch can be used for switching the first optical signal and the second optical signal, and the rear-end link is kept unchanged through the time division multiplexing technology, so that the consistency of the whole link is ensured, other errors are prevented from being introduced in the processing process of the first optical signal and the second optical signal, and the accuracy of the dispersion measurement result is ensured.
In some other embodiments of the present invention, the switching between the first optical signal and the second optical signal may also be achieved by a programmable switch. Specifically, after determining the first phase difference according to the third signal and the demodulated first sub-signal in step S3, the programmable switch receives the instruction to switch the channel after the processing of the first optical signal is finished, transmits the second optical signal generated by the second signal generating module 20 to the modulating module 30, and starts to process the second optical signal.
Of course, the present invention is not limited to the specific form of the switch module 70, as long as the two optical signals can be switched.
Further, in step S7, the step of determining the dispersion coefficient based on the wavelength of the first optical signal, the wavelength of the second optical signal, the first phase difference, the second phase difference, and the length of the optical fiber link includes:
s71, determining the difference value of the first phase difference and the second phase difference to obtain a first difference value;
s72, determining the difference between the wavelength of the first optical signal and the wavelength of the second optical signal to obtain a second difference value;
s73, determining a dispersion measurement value according to the first difference value and the second difference value;
and S74, determining the dispersion coefficient according to the dispersion measured value and the length of the optical fiber link.
It should be understood that the dispersion of an optical fiber link is generally expressed in terms of the dispersion coefficient D, which is defined as the average population experiment over a unit wavelength interval over a unit length of the optical fiber link, with the dispersion coefficient in units of ps/(nm · km).
Alternatively, the dispersion coefficient is determined according to the following formula:
wherein L represents the length of the optical fiber link, DLRepresents a dispersion measurement, D represents a dispersion coefficient, wherein,
representing a first difference and a lambda representing a second difference.
Optionally, the optical fiber link has a length of 10km to 250 km. It should be noted that the length of the optical fiber link is closely related to the demodulation module, and therefore the length of the optical fiber link cannot be too large, otherwise the demodulation module cannot detect the optical signal, but the avalanche type photodetector is adopted in this embodiment, compared with a common photodetector, the avalanche type photodetector has higher detection sensitivity for the optical signal, and has a wider detection range, and therefore the optical signal can still be detected even if the optical fiber link is longer; on the other hand, the length of the optical fiber link cannot be too short, otherwise the dispersion phenomenon is not obvious. Based on the reasons, the invention sets the length of the optical fiber link to be 10 km-250 km, ensures that the avalanche photodetector can detect the optical signal and improves the accuracy of the dispersion measurement result.
Therefore, the dispersion coefficient can be determined according to the actual length of the optical fiber link by the optical fiber link dispersion measurement method based on time division multiplexing, and the subsequent support for dispersion compensation is facilitated.
The beneficial effects of the invention are that:
the invention provides a system and a method for measuring optical fiber link dispersion based on time division multiplexing, wherein a first optical signal and a second optical signal are transmitted to a modulation module in a time-sharing mode, the first optical signal and the second optical signal are modulated by using a third signal with preset frequency, then the first optical signal and the second optical signal are demodulated after passing through an optical fiber link, and the demodulated first sub-signal and the demodulated second sub-signal are subjected to frequency mixing and phase discrimination with the preset frequency to obtain two paths of phase differences.
In the description of the present invention, the terms "first" and "second" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implying any number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless specifically defined otherwise.
In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, various embodiments or examples described in this specification can be combined and combined by those skilled in the art.
While the present application has been described in connection with various embodiments, other variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed application, from a review of the drawings, the disclosure, and the appended claims. In the claims, the word "comprising" does not exclude other elements or steps, and the word "a" or "an" does not exclude a plurality. A single processor or other unit may fulfill the functions of several items recited in the claims. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage.
The foregoing is a more detailed description of the invention in connection with specific preferred embodiments and it is not intended that the invention be limited to these specific details. For those skilled in the art to which the invention pertains, several simple deductions or substitutions can be made without departing from the spirit of the invention, and all shall be considered as belonging to the protection scope of the invention.
Claims (10)
1. An optical fiber link dispersion measurement system based on time division multiplexing is characterized by comprising a first signal generation module, a second signal generation module, a modulation module, a demodulation module, a phase discriminator and a measurement module; wherein,
the first signal generation module is used for generating a first optical signal;
the second signal generation module is used for generating a second optical signal;
the modulation module is configured to modulate the first optical signal and the second optical signal respectively by using a third signal with a preset frequency to obtain a first sub-signal and a second sub-signal, and transmit the first sub-signal and the second sub-signal to the demodulation module by using an optical fiber link;
the demodulation module is used for demodulating the first sub-signal and the second sub-signal and transmitting the demodulated first sub-signal and the demodulated second sub-signal to the phase discriminator;
the phase discriminator is used for determining a first phase difference according to the third signal and the demodulated first sub-signal, and determining a second phase difference according to the third signal and the demodulated second sub-signal;
the measurement module is configured to determine a dispersion coefficient according to the first phase difference, the second phase difference, the wavelength of the first optical signal, the wavelength of the second optical signal, and the length of the optical fiber link.
2. The time division multiplexing based optical fiber link dispersion measurement system of claim 1, wherein the first signal generation module and the second signal generation module comprise lasers.
3. The time division multiplexing based optical fiber link dispersion measurement system of claim 2, wherein the modulation module comprises a voltage controlled oscillator and a fiber intensity modulator connected to the voltage controlled oscillator;
the voltage-controlled oscillator is used for generating a third signal with preset frequency and sending the third signal to the optical fiber intensity modulator;
the optical fiber intensity modulator is configured to modulate the first optical signal and the second optical signal with the third signal, respectively.
4. The time division multiplexing based optical fiber link dispersion measurement system of claim 3, wherein the demodulation module comprises at least an avalanche photodetector.
5. The time division multiplexing based optical fiber link dispersion measurement system of claim 1, further comprising a switching module for connecting the first signal generation module or the second signal generation module to the modulation module on command in a time division multiplexed manner.
6. A method for measuring dispersion of an optical fiber link based on time division multiplexing, which is applied to the system for measuring dispersion of an optical fiber link based on time division multiplexing according to any one of claims 1 to 5;
the method comprises the following steps:
receiving a first optical signal, and modulating the first optical signal by using a third signal with a preset frequency to obtain a first sub-signal;
after the first sub-signal is transmitted by using an optical fiber link, demodulating the first sub-signal;
determining a first phase difference according to the third signal and the demodulated first sub-signal;
receiving a second optical signal, and modulating the second optical signal by using a third signal with a preset frequency to obtain a second sub-signal;
after the second sub-signal is transmitted by using an optical fiber link, demodulating the second sub-signal;
determining a second phase difference according to the third signal and the demodulated second sub-signal;
and determining the dispersion coefficient according to the wavelength of the first optical signal, the wavelength of the second optical signal, the first phase difference, the second phase difference and the length of the optical fiber link.
7. The method according to claim 6, wherein the frequency of the demodulated first sub-signal and the frequency of the demodulated second sub-signal are equal to a predetermined frequency of the third signal.
8. The method of claim 6, wherein the step of determining the dispersion coefficient based on the wavelength of the first optical signal, the wavelength of the second optical signal, the first phase difference, the second phase difference, and the length of the optical fiber link comprises:
determining a difference value between the first phase difference and the second phase difference to obtain a first difference value;
determining the difference between the wavelength of the first optical signal and the wavelength of the second optical signal to obtain a second difference value;
determining a dispersion measurement value according to the first difference value and the second difference value;
and determining the dispersion coefficient according to the dispersion measured value and the length of the optical fiber link.
9. The method of time division multiplexing-based optical fiber link dispersion measurement according to claim 8, wherein the dispersion coefficient is determined according to the following formula:
wherein L represents the length of the optical fiber link, DLRepresents the dispersion measurement, D represents the dispersion coefficient, wherein,
representing a first difference and a lambda representing a second difference.
10. The method of claim 6, wherein the optical fiber link has a length of 10km to 250 km.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111112771.6A CN113972950A (en) | 2021-09-18 | 2021-09-18 | Optical fiber link dispersion measurement system and method based on time division multiplexing |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111112771.6A CN113972950A (en) | 2021-09-18 | 2021-09-18 | Optical fiber link dispersion measurement system and method based on time division multiplexing |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN113972950A true CN113972950A (en) | 2022-01-25 |
Family
ID=79586783
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111112771.6A Pending CN113972950A (en) | 2021-09-18 | 2021-09-18 | Optical fiber link dispersion measurement system and method based on time division multiplexing |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113972950A (en) |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4551019A (en) * | 1983-06-06 | 1985-11-05 | Northern Telecom Limited | Measuring chromatic dispersion of fibers |
| US20020118356A1 (en) * | 2001-02-16 | 2002-08-29 | Wolfgang Hoyer | Apparatus and method for measuring the chromatic dispersion of an optical transmission link |
| US20190334616A1 (en) * | 2017-01-06 | 2019-10-31 | Huawei Technologies Co., Ltd | Method for measuring dispersion coefficient of optical fiber and network device |
| CN112816180A (en) * | 2020-12-27 | 2021-05-18 | 苏州六幺四信息科技有限责任公司 | Optical fiber dispersion measuring method and measuring device |
-
2021
- 2021-09-18 CN CN202111112771.6A patent/CN113972950A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4551019A (en) * | 1983-06-06 | 1985-11-05 | Northern Telecom Limited | Measuring chromatic dispersion of fibers |
| US20020118356A1 (en) * | 2001-02-16 | 2002-08-29 | Wolfgang Hoyer | Apparatus and method for measuring the chromatic dispersion of an optical transmission link |
| US20190334616A1 (en) * | 2017-01-06 | 2019-10-31 | Huawei Technologies Co., Ltd | Method for measuring dispersion coefficient of optical fiber and network device |
| CN112816180A (en) * | 2020-12-27 | 2021-05-18 | 苏州六幺四信息科技有限责任公司 | Optical fiber dispersion measuring method and measuring device |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN110224776B (en) | High-precision optical fiber time transmission system and method | |
| Dimmick et al. | Optical dispersion monitoring technique using double sideband subcarriers | |
| US20040208523A1 (en) | Swept frequency reflectometry using an optical signal with sinusoidal modulation | |
| JP3904711B2 (en) | System for testing an optical component and method for generating a test signal for broadcast to multiple locations for testing an optical component | |
| US10530491B2 (en) | Coherent optical receiver, device and method for detecting inter-lane skew in coherent optical receiver | |
| CN109547098B (en) | Microwave photon time delay measurement calibrating device | |
| JPH11127113A (en) | Remote monitoring for optical transmission system using line monitor signal | |
| Lin et al. | Differentiator-based photonic instantaneous frequency measurement for radar warning receiver | |
| CN103490816A (en) | System and method for passive transmission of microwave frequency signals | |
| CN111698032B (en) | Single-fiber one-way time transmission method and system | |
| CN113098595A (en) | Method, system and device for measuring group delay of few-mode optical fiber differential mode | |
| US6025949A (en) | Line monitoring of an optical transmission system using pilot signals | |
| CN108390718A (en) | The measuring device and method of optical signal to noise ratio in optical fiber telecommunications system | |
| JP2004282693A (en) | System and method for rapidly achieving optimum dispersion in optical transmission system | |
| US10263697B2 (en) | Method and apparatus for monitoring chromatic dispersion in optical communications network | |
| CN113972950A (en) | Optical fiber link dispersion measurement system and method based on time division multiplexing | |
| CN108540219A (en) | A kind of coherent optical heterodyne communicatio measurement method of parameters, device based on frequency shift modulation | |
| CN108603803A (en) | A kind of method and the network equipment measuring fiber dispersion coefficient | |
| CN102957477B (en) | Signal detecting method and optical signal reception system | |
| CN108429580B (en) | The measuring system and method for arbitrary point OSNR in a kind of optic communication links | |
| CN104980222A (en) | Time transfer device and method | |
| US11867540B2 (en) | Brillouin optical time domain reflectometer with ultra-high spatial resolution based on bipolar differential phase encoding | |
| JP7113548B1 (en) | Method and system for generating time-of-day timing signals | |
| CN113572535A (en) | Method and device for capturing communication laser signal and laser communication system | |
| Liu et al. | Asymmetric channel attack against practical round-trip fiber time synchronization system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |