CN103812593A - High-accuracy distributed optical fibre time synchronization system - Google Patents
High-accuracy distributed optical fibre time synchronization system Download PDFInfo
- Publication number
- CN103812593A CN103812593A CN201410060009.1A CN201410060009A CN103812593A CN 103812593 A CN103812593 A CN 103812593A CN 201410060009 A CN201410060009 A CN 201410060009A CN 103812593 A CN103812593 A CN 103812593A
- Authority
- CN
- China
- Prior art keywords
- time
- optical fiber
- module
- center
- optical
- 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
- Optical Communication System (AREA)
- Synchronisation In Digital Transmission Systems (AREA)
- Electric Clocks (AREA)
Abstract
The invention discloses a high-accuracy distributed optical fibre time synchronization system. The high-accuracy distributed optical fibre time synchronization system comprises an optical fibre time synchronization centre, a passive light distribution network and a plurality of optical fibre time synchronization units, wherein the optical fibre time synchronization centre is located at the combining end of the passive light distribution network, and each of the optical fibre time synchronization units is located at each branching end of the passive light distribution network. According to the high-accuracy distributed optical fibre time synchronization system disclosed by the invention, point-to-multipoint connection and connection control are realized by the passive light distribution network and a time division multiple access technology, and high-accuracy time comparison among points is realized by virtue of a bidirectional time comparison method, thus realizing high-accuracy distributed time synchronization.
Description
Technical field
The present invention relates to optical fiber time-frequency Transfer Technology neck system, the specifically two-way time Compare System of a kind of high accuracy distribution type fiber-optic.
Background technology
High-precision Time synchronization technique has important using value in fields such as satellite navigation, Aero-Space, survey of deep space, geological mapping, communication, electric power transfer and scientific research and meterings.Current traditional precise synchronization technology mainly contains that GPS looks altogether, satellite dual-time is than equity.GPS looks the required equipment of method is relatively simple altogether, and cost is low, but precision is difficult to reach nanosecond order.Two Way Satellite Time Transfer, to realizing high-precision time synchronized, can reach magnitude of subnanosecond, but need to utilize specific satellite communication link.Because the stability of free space link is bad, be easily interfered, its precision is difficult to further improve, and has the problem such as fail safe and apparatus expensive.
Optical fibre channel has than free space path stability high (particularly at short notice yardstick on), loss is low, little, bandwidth advantages of higher is affected by the external environment.Last century, the eighties just caused researcher's concern.Along with the fast development of optical fiber communication, optical-fiber network technology, and the raising that timing tracking accuracy etc. is required, the time synchronized based on optical fiber has caused increasing researcher's concern, has obtained sizable progress, and obtains certain applications.
At present, mainly contain two kinds of methods of utilizing optical fiber to carry out time synchronized.One is based on optical fiber synchronous digital hierarchy (SDH:Synchronous Digital Hierarchy) link and equipment, realizes time synchronized by insert temporal information in SDH time slot.The method can directly be utilized traditional SDH equipment, but due to the asymmetry of physical link and the uncertainty of SDH equipment pointer adjustment, the synchronization accuracy of report is in tens nanoseconds at present.Another kind of optical fiber time synchronous method is that directly full optical channel and the special time synchronism equipment based on bottom carries out two-way time comparison.The method can effectively guarantee the symmetry of physical link, and existing synchronization accuracy is better than the experiment report of 1 nanosecond.
The optical fiber time synchronization scenario of existing bibliographical information is substantially all point-to-point.In a lot of practical applications, synchronous as multiple equipment in navigator fix station, needs the distributed high-accuracy time synchronized of point-to-multipoint.In Technology of American Deep Space Network, adopt a kind of distributed Time Synchronizing based on electrical distributor and point-to-point optical fiber link.But electrical distributor needs the conversion of light/electricity/light and electric processing, and is active equipment, not only can introduce extra unsteadiness, and maintenance, difficult management.
Summary of the invention
The object of the invention is to overcome above-mentioned the deficiencies in the prior art, provide a kind of high accuracy distribution type fiber-optic two-way clock synchronization system, realize the time-sharing multiplex of multiple optical fiber time lock units to up link, avoid data collision.
Technical solution of the present invention is as follows:
A kind of high accuracy distribution type fiber-optic clock synchronization system, its feature is, comprise: the synchronous center of optical fiber time, passive optical distribution network and multiple optical fiber time lock unit, described optical fiber time is synchronously centered close to the terminal of closing of passive optical distribution network, and described each optical fiber time lock unit lays respectively at each point of terminal of passive optical distribution network.
The synchronous center of described optical fiber time comprises: center control and processing module, centre time coding/decoding module, centre time interval test module, center light transceiver module and timer;
Described center is controlled and processing module, for control centre's time coding/decoding module, centre time interval test module, center light transceiver module and timer, the two-way time comparison of point-to-multipoint control, timesharing that completes time division multiple access is controlled, monitoring and the maintenance of system mode.
Described centre time coding/decoding module, the center at the synchronous center of optical fiber time is controlled and processing module control time coding/decoding module, for the Code And Decode of deadline code, encoding function is exported to optical transceiver module by the geocoding of the timing signal from center time-frequency standard (as 1pps, 10pps etc.) and temporal information, control information, two-way contrastive test result and current optical fiber time lock unit in downgoing time synchronous code; Decoding function decodes the address of corresponding timing signal, temporal information and optical fiber time lock unit from the timing code from optical fiber time lock unit, timing signal is passed to time interval test module, the address of optical fiber time lock unit and temporal information are passed to center control and processing module.
Described centre time interval test module, the center at the synchronous center of optical fiber time is controlled and processing module control time interval test module, for the time difference between timing signal and the center time-frequency standard timing signal of test center's time coding/decoding module output;
Described center light transceiver module, the operating state with processing module control optical transceiver module is controlled at the center at the synchronous center of optical fiber time, be used for the light signal switching electrical signals from uplink fiber path, and pass to centre time coding/decoding module after reverting to timing code; And the timing code of centre time coding/decoding module output is modulated on light signal along downlink fiber path, and be sent to optical fiber time lock unit through passive optical distribution network;
Described timer, the switch with processing module control timer is controlled at the center at the synchronous center of optical fiber time, controls and records each optical fiber time lock unit with processing module and reach optical fiber time and synchronize moment at center for completing the center at the synchronous center of optical fiber time.
Described passive distribution optical-fiber network comprises passive optical splitter, optical fiber and bidirectional optical amplifier.
Described optical fiber time lock unit comprises: time coding/decoding module, optical transceiver module, control and processing module, time interval test module, optical switch and timing information adjusting module;
Described control and processing module, control time coding/decoding module, time interval test module, optical transceiver module optical switch and timing information adjustment unit, synchronize two-way time of connection control, timesharing at center and compare and control and clock correction is calculated for completing with optical fiber time.
Described time coding/decoding module, the control of optical fiber time lock unit and processing module control time coding/decoding module, for the coding and decoding function of deadline code.The geocoding of the timing signal from local user's clock, temporal information, this optical fiber time lock unit is exported to optical transceiver module by encoding function; Decoding function decodes the address of corresponding timing signal, temporal information, current optical fiber time lock unit and the delay inequality of optical fiber time synchronous center test etc. from the timing code from the synchronous center of optical fiber time;
Described time interval test module, controls and processing module control time interval test module, for the time difference between the timing signal of testing time coding/decoding module output and the timing signal of local time-frequency standard output.
Described optical transceiver module, controls and processing module control optical transceiver module operating state, for by the light signal switching electrical signals from downlink fiber path, reverts to timing code and passes to time coding/decoding module; And timing code is modulated on light signal and is sent along uplink fiber path;
Described optical switch module, the break-make of control and processing module control optical switch, for the switch control of upstream data.
Described timing information adjusting module, controls and processing module control timing information adjusting module, for the adjustment of local timing information, prevents that uplink timing code from conflicting in link.
Compared with prior art, beneficial effect of the present invention is as follows:
(1) adopt passive optical network structure, be easy to administer and maintain;
(2) overcome the asymmetry of transmission link;
(3) in distributed network, do not need the conversion of light/electricity/light and electric processing, adopt Passive Optical Components, can not introduce extra unsteadiness.
Accompanying drawing explanation
Fig. 1 is the structural representation of the embodiment of the two-way clock synchronization system of high accuracy distribution type fiber-optic of the present invention;
Fig. 2 is the course of work schematic diagram of the two-way clock synchronization system embodiment of high accuracy distribution type fiber-optic of the present invention.
Embodiment
Provide specific embodiment of the present invention below in conjunction with accompanying drawing.The present embodiment is implemented as prerequisite take technical scheme of the present invention, provided detailed execution mode and and concrete workflow, but protection scope of the present invention is not limited to following embodiment.
Fig. 1 is the structural representation of the embodiment of the two-way clock synchronization system of high accuracy distribution type fiber-optic of the present invention, and as shown in the figure, wherein, optical branching device and optical fiber form the passive optical distribution network 2 of a 1 × N.The synchronous center 1 of optical fiber time is positioned at the terminal of closing of passive optical distribution network 2.N optical fiber time lock unit 3 lays respectively at N point terminal of passive optical distribution network 2.System completes the comparison of distributed bidirectional time under the control at the synchronous center 1 of optical fiber time.Specifically comprise:
A kind of high accuracy distribution type fiber-optic clock synchronization system, comprise: the synchronous center 1 of optical fiber time, passive optical distribution network 2 and multiple optical fiber time lock unit 3, described optical fiber time is synchronously centered close to the terminal of closing of passive optical distribution network, and described each optical fiber time lock unit lays respectively at each point of terminal of passive optical distribution network.
The synchronous center 1 of described optical fiber time comprises: center is controlled and processing module 1-1, centre time coding/decoding module 1-2, centre time interval test module 1-3, center light transceiver module 1-4 and timer 1-5;
Described center is controlled and processing module, for control centre's time coding/decoding module, centre time interval test module, center light transceiver module and timer, the two-way time comparison of point-to-multipoint control, timesharing that completes time division multiple access is controlled, monitoring and the maintenance of system mode;
Described centre time coding/decoding module, for the Code And Decode of deadline code,
Described coding refers to the geocoding of the timing signal from center time-frequency standard and temporal information, control information, two-way contrastive test result and current optical fiber time lock unit in downgoing time synchronous code, and exports to center light transceiver module;
Described decoding refers to the address that decodes corresponding timing signal, temporal information and optical fiber time lock unit from the timing code from optical fiber time lock unit, and timing signal is transferred to centre time interval test module, the address of optical fiber time lock unit and temporal information are transferred to center control and processing module;
Described centre time interval test module, for the time difference between timing signal and the center time-frequency standard timing signal of the output of measuring fiber time synchronized centre time coding/decoding module;
Described center light transceiver module, for by the light signal switching electrical signals from uplink fiber path, and passes to centre time coding/decoding module after reverting to timing code; And the timing code of centre time coding/decoding module output is modulated on light signal along downlink fiber path, and be sent to optical fiber time lock unit through passive optical distribution network;
Described timer, controls and records each optical fiber time lock unit with processing module and reach optical fiber time and synchronize moment at center for completing the center at the synchronous center of optical fiber time.
Described passive distribution optical-fiber network 2 comprises passive optical splitter 2-1, optical fiber and bidirectional optical amplifier 2-2.
Described optical fiber time lock unit 3 comprises: time coding/decoding module 3-3, optical transceiver module 3-2, control and processing module 3-5, time interval test module 3-4, optical switch 3-1 and timing information adjusting module 3-6;
Described control and processing module, time coding/decoding module, time interval test module, optical transceiver module, optical switch and timing information adjusting module, synchronize two-way time of connection control, timesharing at center and compare and control and clock correction is calculated for completing with optical fiber time;
Described time coding/decoding module, for the Code And Decode of deadline code;
Described coding refers to the geocoding of the timing signal from local user's clock, temporal information, this optical fiber time lock unit is transferred out to optical transceiver module;
Described decoding refers to and from the timing code from the synchronous center of optical fiber time, decodes the address of corresponding timing signal, temporal information, current optical fiber time lock unit and the delay inequality of optical fiber time synchronous center test;
Described time interval test module, for the time difference between the timing signal of testing time coding/decoding module output and the timing signal of local time-frequency standard output;
Described optical transceiver module, for by the light signal switching electrical signals from downlink fiber path, reverts to timing code and passes to time coding/decoding module; And timing code is modulated on light signal and is sent along uplink fiber path;
Described optical switch module, for the switch control of upstream data.
Described timing information adjustment, for the adjustment of local timing information, prevents that uplink timing code from conflicting in link.
Specific implementation process is as follows:
After center control is receiving time synchronized instruction with processing module 1-1 time, enter the presynchronization stage: first optical fiber time lock unit 3 is made as to current optical fiber time lock unit, enables centre time coding/decoding module 1-2 and send the address of current optical fiber time lock unit to centre time coding/decoding module 1-2.Centre time coding/decoding module 1-2 coding produces the connection request that comprises current optical fiber time lock unit address, and in the time local timing signal being detected, connection request is sent to passive optical distribution network 2 by center light transceiver module 1-4, and center is controlled with processing module 1-1 and is started timer 1-5.
The optical transceiver module 3-2 of optical fiber time lock unit 3 reverts to the signal of telecommunication by the connection request receiving and passes to time coding/decoding module 3-3.Time coding/decoding module 3-3 extracts the address of current optical fiber time lock unit from connection request timing code, and it is transferred to and is controlled and processing module 3-5.Control from processing module 3-5 the address of the current optical fiber time lock unit obtaining and the address that this optical fiber time lock unit has been encoded are compared: if the address of the address of current optical fiber time lock unit and this optical fiber time lock unit is different, controls with processing module 3-5 and continue to monitor.If the address of current optical fiber time lock unit is identical with the address of this optical fiber time lock unit, control enables with the transmitting that processing module 3-5 opens optical switch 3-1, simultaneously, enable time coding/decoding module 3-3 coding and produce connection confirmation, and in the time controlling and processing module 3-5 local timing signal detected, to connect and confirm to send to the center light transceiver module 1-4 at the synchronous center 1 of optical fiber time by passive optical distribution network 2 through optical transceiver module 3-2, and send and connect the transmission of closing optical switch 3-1 after confirming and enable.Connect and confirm to control and processing module 1-1 through center light transceiver module 1-4 and centre time coding/decoding module 1-2 arrival center successively.Center is controlled with processing module 1-1 and is confirmed and being connected of current optical fiber time lock unit, and before timer 1-5 expires, the synchronous revenue centre control of optical fiber time and processing module 1-1 record connection confirmation signal arrival optical fiber time and synchronize the time t ' at center
1, and the timer 1-5 that resets.Then the synchronous center 1 of optical fiber time continues to send connection request to next optical fiber time lock unit, and same record connects the time t ' at the confirmation signal arrival synchronous center of optical fiber time
2then continue to send connection request to next optical fiber time lock unit, until the synchronous center 1 of optical fiber time successively with the connection request of each optical fiber time lock unit with confirm after, center is controlled with processing module 1-1 and is synchronizeed the time t ' at center according to the connection confirmation signal arrival optical fiber time of each optical fiber time lock unit
i, check t '
iwhether be greater than 1, if t '
ibe greater than 1, t
i=t '
i-1; Otherwise, t
i=t '
i.Center is controlled with processing module 1-1 and is detected t
irelation each other, if detect t
irelation each other does not meet | t
j-t
i|>=Δ t, i, j=1,2 ..., N and i ≠ j, the adjustment amount of numbering order computation from big to small and need to adjust timing information optical fiber time lock unit timing information with processing module 1-1 by optical fiber time lock unit is controlled at the synchronous center of optical fiber time, and the adjustment amount of corresponding timing information is Δ t
i=t
i+ (Δ t-|t
j-t
i|).The synchronous center of optical fiber time is controlled with processing module 1-1 after calculating the optical fiber time lock unit timing information adjustment amount that need to adjust local timing information, and the address and the corresponding optical fiber time synchronized unit timing information adjustment amount that enable centre time coding/decoding module 1-2 and need to adjust timing information optical fiber time lock unit send centre time coding/decoding module 1-2 to.Centre time coding/decoding module 1-2 coding produces and comprises address and the corresponding optical fiber time synchronized unit timing information adjustment amount that need to adjust timing information optical fiber time lock unit, and in the time local timing signal being detected, connection request is sent to passive optical distribution network 2 by optical transceiver module 1-4.Optical fiber time lock unit is after receiving the request of adjustment, according to the adjustment amount Δ t receiving
iadjust local timing information by timing information adjusting module.The timing information of all optical fiber time lock units adjust complete after, enter two-way comparison stage time.
In two-way comparison stage time, the centre time coding/decoding module 1-2 at the synchronous center 1 of optical fiber time produces the timing code that comprises time-frequency standard timing signal, temporal information and two-way contrastive test result, and is receiving that each local timing signal connecting after confirming sends to current optical fiber time lock unit the zero hour; Simultaneously, in the time that timing information is effective, optical fiber time synchronized unit i controls with processing module and opens optical switch, the time coding/decoding module of optical fiber time lock unit i produces the timing code that comprises user clock timing signal and temporal information, sends to the synchronous center 1 of optical fiber time.The synchronous center 1 of optical fiber time and optical fiber time lock unit i are receiving after the other side's timing code, from timing code, extract timing signal and temporal information by time coding/decoding module separately, and test out the timing signal that extracts and the delay inequality of local clock timing signal separately by time interval test module separately.The delay inequality that test module 1-3 of synchronous 1 time interval of center of optical fiber time records is coded in and in downgoing time synchronous code, sends to corresponding optical fiber time lock unit i through time coding/decoding module 1-2.Optical fiber time lock unit i utilize the local delay inequality of surveying and and the delay inequality that receives from the synchronous center of optical fiber time calculate clock correction, and the clock correction of calculating and the timing signal that recovers are exported to local user's clock, make it to synchronize with optical fiber time central synchronous.
Due to the dynamic change of Small frequency offset, transmission path time delay etc. that two places clock exists, in two-way comparison stage time, may need the timing information of each optical fiber time lock unit i to adjust, to avoid the conflict of adjacent node.The synchronous center of optical fiber time is controlled the timing code that receives each optical fiber time lock unit with processing module 1-1 and is arrived optical fiber time and synchronize after center, calculating actual time of arrival t '
awith specified time of arrival t
adifference DELTA t
a=t '
a-t
a, and by this differential coding in descending timing code, be broadcast to all optical fiber time lock units, corresponding optical fiber time synchronized unit receives after descending timing code, extracts difference, adjusts local timing information
Finish indication or comparison while reaching precision receiving, enter comparison ending phase, complete comparison end operation; Otherwise, proceed two-way time comparison.
Claims (4)
1. a high accuracy distribution type fiber-optic clock synchronization system, it is characterized in that, comprise: the synchronous center of optical fiber time, passive optical distribution network and multiple optical fiber time lock unit, described optical fiber time is synchronously centered close to the terminal of closing of passive optical distribution network, and described each optical fiber time lock unit lays respectively at each point of terminal of passive optical distribution network.
2. high accuracy distribution type fiber-optic clock synchronization system according to claim 1, it is characterized in that, the synchronous center of described optical fiber time comprises: center control and processing module, centre time coding/decoding module, centre time interval test module, center light transceiver module and timer;
Described center is controlled and processing module, for control centre's time coding/decoding module, centre time interval test module, center light transceiver module and timer, the two-way time comparison of point-to-multipoint control, timesharing that completes time division multiple access is controlled, monitoring and the maintenance of system mode;
Described centre time coding/decoding module, for the Code And Decode of deadline code,
Described coding refers to the geocoding of the timing signal from center time-frequency standard and temporal information, control information, two-way contrastive test result and current optical fiber time lock unit in downgoing time synchronous code, and exports to center light transceiver module;
Described decoding refers to the address that decodes corresponding timing signal, temporal information and optical fiber time lock unit from the timing code from optical fiber time lock unit, and timing signal is transferred to centre time interval test module, the address of optical fiber time lock unit and temporal information are transferred to center control and processing module;
Described centre time interval test module, for the time difference between timing signal and the center time-frequency standard timing signal of the output of measuring fiber time synchronized centre time coding/decoding module;
Described center light transceiver module, for by the light signal switching electrical signals from uplink fiber path, and passes to centre time coding/decoding module after reverting to timing code; And the timing code of centre time coding/decoding module output is modulated on light signal along downlink fiber path, and be sent to optical fiber time lock unit through passive optical distribution network;
Described timer, controls and records each optical fiber time lock unit with processing module and reach optical fiber time and synchronize moment at center for completing the center at the synchronous center of optical fiber time.
3. high accuracy distribution type fiber-optic clock synchronization system according to claim 1, is characterized in that, described passive distribution optical-fiber network comprises passive optical splitter, optical fiber and bidirectional optical amplifier.
4. high accuracy distribution type fiber-optic clock synchronization system according to claim 1, it is characterized in that, described optical fiber time lock unit comprises: time coding/decoding module, optical transceiver module, control and processing module, time interval test module, optical switch and timing information adjusting module;
Described control and processing module, control time coding/decoding module, time interval test module, optical transceiver module, optical switch and timing information adjusting module, synchronize two-way time of connection control, timesharing at center and compare and control and clock correction is calculated for completing with optical fiber time;
Described time coding/decoding module, for the Code And Decode of deadline code;
Described coding refers to the geocoding of the timing signal from local user's clock, temporal information, this optical fiber time lock unit is transferred out to optical transceiver module;
Described decoding refers to and from the timing code from the synchronous center of optical fiber time, decodes the address of corresponding timing signal, temporal information, current optical fiber time lock unit and the time difference of optical fiber time synchronous center test;
Described time interval test module, for the time difference between the timing signal of testing time coding/decoding module output and the timing signal of local time-frequency standard output;
Described optical transceiver module, for by the light signal switching electrical signals from downlink fiber path, reverts to timing code and passes to time coding/decoding module; And timing code is modulated on light signal and is sent along uplink fiber path;
Described optical switch module, for the switch control of upstream data.
Described timing information adjusting module, for the adjustment of local timing information, prevents that uplink timing code from conflicting in link.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410060009.1A CN103812593B (en) | 2014-02-21 | 2014-02-21 | High precision distribution type fiber-optic clock synchronization system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410060009.1A CN103812593B (en) | 2014-02-21 | 2014-02-21 | High precision distribution type fiber-optic clock synchronization system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN103812593A true CN103812593A (en) | 2014-05-21 |
| CN103812593B CN103812593B (en) | 2016-06-08 |
Family
ID=50708852
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201410060009.1A Active CN103812593B (en) | 2014-02-21 | 2014-02-21 | High precision distribution type fiber-optic clock synchronization system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN103812593B (en) |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2016000287A1 (en) * | 2014-07-04 | 2016-01-07 | 上海交通大学 | High-precision optical fiber bidirectional time comparison method and system |
| CN105790845A (en) * | 2016-04-08 | 2016-07-20 | 上海交通大学 | Single-fiber bidirectional time-division multiplexing light amplification apparatus |
| CN106209295A (en) * | 2016-07-20 | 2016-12-07 | 上海交通大学 | The control method of two-way time division multiplex Time Transmission system |
| CN106788840A (en) * | 2016-11-30 | 2017-05-31 | 中国科学院国家授时中心 | A kind of high-precision optical fiber method for synchronizing time based on optical fiber Frequency Transfer |
| CN109921872A (en) * | 2018-11-29 | 2019-06-21 | 上海交通大学 | Optical fiber time transmission system and transmission method |
| CN109981211A (en) * | 2019-03-21 | 2019-07-05 | 上海交通大学 | Distribution type fiber-optic temporal frequency combines transmission system and transmission method |
| CN111770396A (en) * | 2020-06-04 | 2020-10-13 | 中国人民解放军国防科技大学 | Signal generating and comparing device and method based on optical fiber transmission |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20020018475A1 (en) * | 1998-07-22 | 2002-02-14 | Yoram Ofek | Switching with multiple time references |
| CN102299743A (en) * | 2011-09-23 | 2011-12-28 | 中国科学院国家授时中心 | Post-compensation method for transmission time delay during optical fiber time transmission |
| CN103427976A (en) * | 2013-08-23 | 2013-12-04 | 上海交通大学 | High-precision time synchronization method for distributed optical fibers |
| CN103427842A (en) * | 2013-08-07 | 2013-12-04 | 上海交通大学 | Coding and decoding method and coding and decoding device for high-precision time transfer |
-
2014
- 2014-02-21 CN CN201410060009.1A patent/CN103812593B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20020018475A1 (en) * | 1998-07-22 | 2002-02-14 | Yoram Ofek | Switching with multiple time references |
| CN102299743A (en) * | 2011-09-23 | 2011-12-28 | 中国科学院国家授时中心 | Post-compensation method for transmission time delay during optical fiber time transmission |
| CN103427842A (en) * | 2013-08-07 | 2013-12-04 | 上海交通大学 | Coding and decoding method and coding and decoding device for high-precision time transfer |
| CN103427976A (en) * | 2013-08-23 | 2013-12-04 | 上海交通大学 | High-precision time synchronization method for distributed optical fibers |
Non-Patent Citations (1)
| Title |
|---|
| 王苏北等: "一种光纤双向时间比对时间码的设计与验证", 《光通信技术》 * |
Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2016000287A1 (en) * | 2014-07-04 | 2016-01-07 | 上海交通大学 | High-precision optical fiber bidirectional time comparison method and system |
| US10063315B2 (en) | 2014-07-04 | 2018-08-28 | Shanghai Jiao Tong University | Method and system for high-precision two-way fiber-optic time transfer |
| CN105790845A (en) * | 2016-04-08 | 2016-07-20 | 上海交通大学 | Single-fiber bidirectional time-division multiplexing light amplification apparatus |
| CN105790845B (en) * | 2016-04-08 | 2017-12-26 | 上海交通大学 | Single fiber bi-directional time division multiplexing optical amplification device |
| CN106209295A (en) * | 2016-07-20 | 2016-12-07 | 上海交通大学 | The control method of two-way time division multiplex Time Transmission system |
| CN106788840A (en) * | 2016-11-30 | 2017-05-31 | 中国科学院国家授时中心 | A kind of high-precision optical fiber method for synchronizing time based on optical fiber Frequency Transfer |
| CN106788840B (en) * | 2016-11-30 | 2018-06-05 | 中国科学院国家授时中心 | A kind of high-precision optical fiber method for synchronizing time based on optical fiber Frequency Transfer |
| CN109921872A (en) * | 2018-11-29 | 2019-06-21 | 上海交通大学 | Optical fiber time transmission system and transmission method |
| CN109921872B (en) * | 2018-11-29 | 2020-11-10 | 上海交通大学 | Optical fiber time transmission system and transmission method |
| CN109981211A (en) * | 2019-03-21 | 2019-07-05 | 上海交通大学 | Distribution type fiber-optic temporal frequency combines transmission system and transmission method |
| CN111770396A (en) * | 2020-06-04 | 2020-10-13 | 中国人民解放军国防科技大学 | Signal generating and comparing device and method based on optical fiber transmission |
| CN111770396B (en) * | 2020-06-04 | 2022-02-11 | 中国人民解放军国防科技大学 | Signal generating and comparing device and method based on optical fiber transmission |
Also Published As
| Publication number | Publication date |
|---|---|
| CN103812593B (en) | 2016-06-08 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103812593A (en) | High-accuracy distributed optical fibre time synchronization system | |
| CN102315985B (en) | Time synchronization precision test method for intelligent device adopting IEEE1588 protocols | |
| CN101557258B (en) | Method and system for using synchronous digital hierarchy (SDH) to realize high-accuracy time synchronization | |
| CN102136900B (en) | Time synchronization method for passive optical network, device and system | |
| CN106451763B (en) | A kind of intelligent substation station level bus network system without global synchronization system | |
| CN104168077B (en) | High accuracy optical fiber bidirectional time comparison method and system | |
| CN103368137B (en) | Multi-terminal self-repairing data synchronization differential protection method based on network self-repairing | |
| CN102638324B (en) | Method and device for realizing precise time synchronization | |
| CN102833025B (en) | E1/Ethernet protocol conversion precise delay computational methods, module and transducer | |
| CN106506106B (en) | High-precision time frequency source based on optical fiber time transmission | |
| CN105634641B (en) | Based on architecture for exchanging can cascade network communication accurate timing system and method | |
| CN103442312A (en) | Intelligent power distribution network time synchronization system and method based on PTN+EPON communication system | |
| CN103916204A (en) | Cloud synchronization method of high-precision timing system of optical network | |
| CN103715766A (en) | Ring network distributed bus protection synchronization method | |
| CN104901291A (en) | Intelligent fiber differential protection synchronization method based on Beidou time service | |
| CN105991205A (en) | Verifiable and adjustable full synchronous communication network, and implementation method thereof | |
| WO2021008532A1 (en) | Active antenna unit delay alignment method and apparatus and active antenna unit | |
| CN102158298B (en) | High-accuracy time frequency delivery method based on synchronous digital hierarchy (SDH) optical network | |
| CN103427976B (en) | Distribution type fiber-optic method for synchronizing time in high precision | |
| CN205050133U (en) | Embedded time system that unites in system | |
| CN101998192A (en) | Method and system for time synchronization on passive optical network | |
| CN205283557U (en) | PTP time synchronizer based on synchronous ethernet | |
| CN103078728B (en) | Clock synchronization system | |
| CN101257361A (en) | Method and net element for performing accurate time transmission through synchronous digital system network | |
| CN105119678A (en) | Synchronous digital hierarchy (SDH)-E1 network based method for realizing precise time protocol (PTP) nanosecond precision transmission |
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 |