CN106877964B - High-precision optical fiber time frequency signal synchronizing network - Google Patents
High-precision optical fiber time frequency signal synchronizing network Download PDFInfo
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- CN106877964B CN106877964B CN201710016495.0A CN201710016495A CN106877964B CN 106877964 B CN106877964 B CN 106877964B CN 201710016495 A CN201710016495 A CN 201710016495A CN 106877964 B CN106877964 B CN 106877964B
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04J—MULTIPLEX COMMUNICATION
- H04J3/00—Time-division multiplex systems
- H04J3/02—Details
- H04J3/06—Synchronising arrangements
- H04J3/062—Synchronisation of signals having the same nominal but fluctuating bit rates, e.g. using buffers
- H04J3/0623—Synchronous multiplexing systems, e.g. synchronous digital hierarchy/synchronous optical network (SDH/SONET), synchronisation with a pointer process
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- 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
- H04B10/03—Arrangements for fault recovery
- H04B10/032—Arrangements for fault recovery using working and protection systems
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- 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
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04J—MULTIPLEX COMMUNICATION
- H04J14/00—Optical multiplex systems
- H04J14/02—Wavelength-division multiplex systems
- H04J14/0227—Operation, administration, maintenance or provisioning [OAMP] of WDM networks, e.g. media access, routing or wavelength allocation
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04J—MULTIPLEX COMMUNICATION
- H04J14/00—Optical multiplex systems
- H04J14/02—Wavelength-division multiplex systems
- H04J14/0287—Protection in WDM systems
- H04J14/0293—Optical channel protection
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04J—MULTIPLEX COMMUNICATION
- H04J3/00—Time-division multiplex systems
- H04J3/02—Details
- H04J3/06—Synchronising arrangements
- H04J3/0635—Clock or time synchronisation in a network
- H04J3/0638—Clock or time synchronisation among nodes; Internode synchronisation
- H04J3/0658—Clock or time synchronisation among packet nodes
- H04J3/0661—Clock or time synchronisation among packet nodes using timestamps
- H04J3/0667—Bidirectional timestamps, e.g. NTP or PTP for compensation of clock drift and for compensation of propagation delays
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04J—MULTIPLEX COMMUNICATION
- H04J3/00—Time-division multiplex systems
- H04J3/16—Time-division multiplex systems in which the time allocation to individual channels within a transmission cycle is variable, e.g. to accommodate varying complexity of signals, to vary number of channels transmitted
- H04J3/1605—Fixed allocated frame structures
- H04J3/1652—Optical Transport Network [OTN]
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04Q—SELECTING
- H04Q11/00—Selecting arrangements for multiplex systems
- H04Q11/0001—Selecting arrangements for multiplex systems using optical switching
- H04Q11/0005—Switch and router aspects
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04Q—SELECTING
- H04Q11/00—Selecting arrangements for multiplex systems
- H04Q11/0001—Selecting arrangements for multiplex systems using optical switching
- H04Q11/0062—Network aspects
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04Q—SELECTING
- H04Q11/00—Selecting arrangements for multiplex systems
- H04Q11/0001—Selecting arrangements for multiplex systems using optical switching
- H04Q11/0005—Switch and router aspects
- H04Q2011/0037—Operation
- H04Q2011/0045—Synchronisation
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04Q—SELECTING
- H04Q11/00—Selecting arrangements for multiplex systems
- H04Q11/0001—Selecting arrangements for multiplex systems using optical switching
- H04Q11/0062—Network aspects
- H04Q2011/0073—Provisions for forwarding or routing, e.g. lookup tables
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- Optical Communication System (AREA)
Abstract
A kind of high-precision optical fiber time frequency signal synchronizing network, including optical fiber, N number of interchanger, M time frequency signal source, wherein, N is 2 or more positive integer, the positive integer that M is 1 or more, each interchanger and time frequency signal source are a network nodes, N+M network node is formed in total, each time frequency signal source is connect with two adjacent interchangers by optical fiber in wherein M time frequency signal source, and each interchanger is connected by the different optical fiber at least three tunnels from other different interchangers or time frequency signal source in N number of interchanger.The present invention uses transmission medium of the optical fiber as time frequency signal synchronizing network; the precision of the homologous synchronization of time frequency signal is very high in whole network; optical fiber link is stablized simultaneously and the transmission of time frequency signal separates, the transparent transmission of time frequency signal and the pretection switch of network may be implemented.
Description
Technical field
The present invention relates to time frequency signal synchronizing network, especially a kind of high-precision optical fiber time frequency signal synchronizing network.
Background technology
Contemporary society has been the Network Society of information-driven, navigator fix, wireless communication, internet, distributed electrical
Net etc. has become essential element in social life.One undeniable the fact is that these technologies are dependent on
In clock synchronous network network, clock synchronous network network provides high-precision time and frequency standards signal as technical foundation, for these applications.
Present clock synchronization scheme most importantly by means of the space-baseds such as GPS/ Big Dippeves navigation positioning system (GNSS) to
Secondly the satellite atomic clock of global broadcast further includes the various ways such as e-Loran, IEEE1588v2, DCF77, NTP, common
Precision is shown in Table 1.
The time synchronization and positioning accuracy of several typical ways on 1 50km scales of table
| GNSS | e-Loran | IEEE1588v2 | DCF77 | NTP | |
| Timing tracking accuracy | 5-50ns | 100ns | >1μs | 2-25μs | >1ms |
| Positioning accuracy | 3-30m | 60m | n/a | n/a | n/a |
These modes are difficult to meet next-generation application demand.The slightly higher GNSS system presence signal of precision first is faint, more
Secondly the shortcomings of diameter error and thus caused area-denial, has increasing need for the cm even positioning accurate of mm magnitudes in precision aspect
The timing tracking accuracy of degree and ps magnitudes, or even also need to the frequency of short-term 1E-15 magnitudes, long-term 1E-18 magnitudes in many fields
The homologous stability of rate.For example after only having timing tracking accuracy to enter ps magnitudes and frequency homologous phase coherence, it could realize more bases
The coherent of ground radar merges, to truly improve detection and the interference performance of existing radar；In addition the second of light clock has been surely
Through entering 1E-15 magnitudes, in order to write the second level definition of second again on higher precision level using light clock, it is necessary to which the world is each
Ground light clock carries out the mutual comparison in the magnitude；The unmanned field risen now also needs the positioning ability of higher precision
The success for promoting it to promote and apply, because positioning accuracy and radar of the pilotless automobile of current Google based on GPS, taking the photograph
As about 150,000 kilometers of the safety traffic mileage that first-class ancillary equipment can be realized, although for single automobile, the numerical value is very
It is surprising, but if it is considered that then much insufficient if effective and safe mileage, for example, Shanghai a morning peak, in effective and safe
30,000,000 kilometers of Cheng Yueyou (1,000,000 automobiles averagely travel 30 kilometers in the same period), if being full pilotless automobile, that
It can simply find out very much that simple 150,000 kilometers of safety traffic mileage is also far from enough.
Invention content
, in order to meet above application demand, the present invention proposes that a kind of high-precision time frequency signal based on optical fiber synchronizes net for this
Network provides the time frequency signal of higher precision for the arbitrary node in network.
Core of the invention thought is by each network node at least through two optical fiber links and other two network sections
Then point connection realizes that optical fiber link is stable and measures by optical fiber link time delay observing and controlling transmitter and receiver, passes through time-frequency
Signal transmitter and receiver realize the transmission of time frequency signal, realize that network route optimization and protection fall by master control borad and switch
It changes, present networks stablize optical fiber link and the transmission of time frequency signal is separately carried out by way of wavelength-division multiplex, can be in the light
The high-precision transparent transmission of time frequency signal is realized on fibre web network.
Technical solution of the invention is as follows：
A kind of high-precision optical fiber time frequency signal synchronizing network, including optical fiber, N number of interchanger, M time frequency signal source, wherein
N is 2 or more positive integer, and the positive integer that M is 1 or more, each interchanger and time frequency signal source are a network nodes, in total
N+M network node is formed, connection relation is as follows：In the M time frequency signal source each time frequency signal source with it is adjacent
Two interchangers are connected by optical fiber, while each interchanger passes through the different optical fiber at least three tunnels in N number of interchanger
It is connected from other different interchangers or time frequency signal source.
The interchanger realizes the function that optical fiber link is stablized and time frequency signal routing optimality selects, by first annular
Device, the first solution wavelength division multiplexer, the first optical fiber link time delay observing and controlling receiver, the first time frequency signal receiver, master control borad, radio frequency
Switch, photoswitch, the first optical fiber link time delay observing and controlling transmitter, the first time frequency signal transmitter, the first wavelength division multiplexer, second
Circulator, third circulator, the second solution wavelength division multiplexer, the second optical fiber link time delay observing and controlling receiver, the second time frequency signal connect
Receipts machine, the second optical fiber link time delay observing and controlling transmitter, the second time frequency signal transmitter, the second wavelength division multiplexer, fourth annular device
Composition.Its connection relation is as follows：The second port of first annular device is connected with the first input optical signal of interchanger, third end
Mouth is connected with the input port of the first solution wavelength division multiplexer；The output port of first solution wavelength division multiplexer is divided into two classes, the first kind
It is the port for the optical wavelength that wavelength is used to transmit optical fiber link time delay observing and controlling desired signal, this section ports and the first optical-fiber time-delay
The input port of observing and controlling receiver is connected, and the second class is the end for the optical wavelength that wavelength is used to transmit time frequency signal and identification information
Mouthful, this section ports is connected with the input port of the first time frequency signal receiver；First optical fiber link time delay observing and controlling receiver
Optical output port is returned with the first port of first annular device to be connected；The microwave time frequency signal of first time frequency signal receiver exports
Port is connected with the first input port of RF switch, the first input port of light wave time frequency signal output port and photoswitch
It is connected, identification information output port is connected with the first input port of master control borad；Other two input port of master control borad point
Not with the delay measurements output end of the first optical fiber link time delay observing and controlling transmitter and the second optical fiber link time delay observing and controlling transmitter
Mouthful it is connected, and the routing control signals output port of the master control borad control signal input mouth with photoswitch and RF switch respectively
It is connected, the identification information output port of the master control borad mark with the first time frequency signal transmitter and the second time frequency signal transmitter respectively
Know information input port to be connected, the first and second output port of time frequency signal of RF switch emits with the first time frequency signal respectively
The microwave time frequency signal input port of machine and the second time frequency signal transmitter is connected, and third output port is then used as the interchanger
Microwave time frequency signal output port, the first and second output port of time frequency signal of photoswitch sends out with the first time frequency signal respectively
The light wave time frequency signal input port for penetrating machine and the second time frequency signal transmitter is connected, and third output port is then used as the exchange
The light wave time frequency signal output port of machine；The output of first optical fiber link time delay observing and controlling transmitter and the first time frequency signal transmitter
Port is connected with the input port of the first wavelength division multiplexer respectively, the output port of the first wavelength division multiplexer and the second circulator
First port is connected, the return light input port of the third port of the second circulator and the first optical fiber link time delay observing and controlling transmitter
It is connected, the first passage light signal output end mouth of the second port of the second circulator as the interchanger.The of third circulator
Two-port netwerk is connected with the second input optical signal of interchanger, the input port phase of third port and the second solution wavelength division multiplexer
Even；The output port of second solution wavelength division multiplexer is divided into two classes, and the first kind is wavelength for transmitting optical fiber link time delay observing and controlling institute
The port of the optical wavelength of signal is needed, this section ports is connected with the input port of the second optical-fiber time-delay observing and controlling receiver, the second class
It is the port for the optical wavelength that wavelength is used to transmit time frequency signal and identification information, this section ports and the second time frequency signal receiver
Input port be connected；The first end of the return optical output port and third circulator of second optical fiber link time delay observing and controlling receiver
Mouth is connected；The time frequency signal output port of second time frequency signal receiver is connected with the second input port of RF switch, light
Wave time frequency signal output port is connected with the second input port of photoswitch, and the second of identification information output port and master control borad
Input port is connected.The output port of second optical fiber link time delay observing and controlling transmitter and the second time frequency signal transmitter is respectively with
The input port of two wavelength division multiplexers is connected, the output port of the second wavelength division multiplexer and the first port phase of fourth annular device
Even, the third port of fourth annular device is connected with the return light input port of the second optical fiber link time delay observing and controlling transmitter, and the 4th
Second channel light signal output end mouth of the second port of circulator as the interchanger.If interchanger needs more multichannel
When, when can increase optical fiber link time delay observing and controlling receiver, time frequency signal receiver, optical fiber link according to above-mentioned connection type
It is defeated to increase optical signal to prolong observing and controlling transmitter, time frequency signal transmitter, wavelength division multiplexer, solution wavelength division multiplexer and circulator
Enter output channel.
The time frequency signal source is by high precision clock, master control borad, RF switch, photoswitch, the first optical fiber link time delay
Observing and controlling transmitter, the first time frequency signal transmitter, the second optical fiber link time delay observing and controlling transmitter, the second time frequency signal transmitter,
First wavelength division multiplexer, the second wavelength division multiplexer, first annular device, the second circulator composition.Its connection relation is as follows：In high precision
The optical frequency time frequency signal output port of clock is connected with the time-frequency input signal port of photoswitch, and the output signal end of photoswitch
Mouthful and respectively as time frequency signal source third channel light signal output end mouth and fourth lane light signal output end mouth and, it is high-precision
The microwave time frequency signal output port of degree clock is connected with the time frequency signal input port of RF switch, two inputs of master control borad
Port, the respectively delay measurements with the first optical fiber link time delay observing and controlling transmitter and the second optical fiber link time delay observing and controlling transmitter
Output port is connected, and the control signal of the microwave time frequency signal routing control signals output port of master control borad and RF switch is defeated
Inbound port is connected, the light wave time frequency signal routing control signals output port of master control borad and the control signal input mouth of photoswitch
It is connected, the identification information output port of the master control borad mark with the first time frequency signal transmitter and the second time frequency signal transmitter respectively
Know information input port to be connected, the first and second output port of time frequency signal of RF switch emits with the first time frequency signal respectively
The microwave time frequency signal input port of machine and the second time frequency signal transmitter is connected；First optical fiber link time delay observing and controlling transmitter and
The output port of first time frequency signal transmitter is connected with the input port of the first wavelength division multiplexer respectively, the first wavelength division multiplexer
Output port be connected with the first port of first annular device, the third port of first annular device and the first optical fiber link time delay are surveyed
The return light input port for controlling transmitter is connected, the first passage light of the second port of first annular device as the time frequency signal source
Signal output port；The output port of second optical fiber link time delay observing and controlling transmitter and the second time frequency signal transmitter is respectively with
The input port of two wavelength division multiplexers is connected, the first port phase of the output port of the second wavelength division multiplexer and the second circulator
Even, the third port of the second circulator is connected with the return light input port of the second optical fiber link time delay observing and controlling transmitter, and second
Second channel light signal output end mouth of the second port of circulator as the time frequency signal source.
Certain described two passes through optical fiber link time delay observing and controlling transmitter and optical fiber by between the network node of optical fiber connection
The combination of chain-circuit time delay observing and controlling receiver realizes that the time delay of optical fiber link is stablized, and is then believed by time frequency signal transmitter and time-frequency
The transmission of time frequency signal is realized in the combination of number receiver, since optical fiber link itself be in stable state at this time, so biography
Defeated time frequency signal also can be stable, will not be influenced by the optic fibre environments noise such as temperature disturbance.Simultaneously when optical fiber link
Prolong observing and controlling launching opportunity and the time delay value of corresponding optical fiber link fed back into master control borad, if the time delay of certain optical fiber all the way have occurred compared with
Big shake or variation, then master control borad will send control signals to RF switch and two time frequency signal transmitters, when making
Frequency signal is along the in addition optical fiber transmission all the way being connect with local switch or time frequency signal source, to reach pretection switch
Purpose.
The features and advantages of the invention are：
(1) present invention uses transmission medium of the optical fiber as time frequency signal synchronizing network, can be realized in whole network
The very high-precision homologous synchronization accuracy of time frequency signal；
(2) present invention stablizes optical fiber link and the transmission of time frequency signal separates, on the basis for realizing that link is stablized first
On, entire fiber optic network is equivalent to a stable transmission channel, and arbitrary time frequency signal may be implemented stablizes transmission, and entire
The performance of transmission network itself and time frequency signal to be transmitted are unrelated, this is equivalent to the transparent transmission for realizing time frequency signal；
(3) Route Selection and pretection switch of network may be implemented in the present invention, in the case of a certain link fails,
It carries out routing rapidly to reselect, to fast implement the transmission again of time frequency signal, without link stabilization when establishing
Between.
Description of the drawings
The structural schematic diagram of Fig. 1 high-precision optical fiber time frequency signal synchronizing networks of the present invention；
The structural schematic diagram of interchanger in Fig. 2 high-precision optical fiber time frequency signal synchronizing networks of the present invention；
The structural schematic diagram in time frequency signal source in Fig. 3 high-precision optical fiber time frequency signal synchronizing networks of the present invention；
The structural schematic diagram of Fig. 4 high-precision optical fiber time frequency signal synchronizing network embodiments of the present invention；
The structural schematic diagram of optical fiber link time delay observing and controlling receiver in Fig. 5 embodiment of the present invention；
The structural schematic diagram of optical fiber link time delay observing and controlling transmitter in Fig. 6 embodiment of the present invention；
The structural schematic diagram of time frequency signal receiver in Fig. 7 embodiment of the present invention；
The structural schematic diagram of time frequency signal transmitter in Fig. 8 embodiment of the present invention.
Specific implementation mode
The invention will be further described with reference to the accompanying drawings and examples, but the protection model of the present invention should not be limited with this
It encloses.
First referring to Fig. 1, Fig. 1 is the structural schematic diagram of high-precision optical fiber time frequency signal synchronizing network of the present invention.It can by figure
See, high-precision optical fiber time frequency signal synchronizing network of the present invention includes optical fiber 1, N number of interchanger 2, M time frequency signal source 3, wherein often
A interchanger and time frequency signal source are all a network nodes, form N+M network node in total, and connection relation is as follows：Institute
Each time frequency signal source is connect with two adjacent interchangers by optical fiber in the M time frequency signal source stated, while described N number of
Each interchanger is connected by the different optical fiber at least three tunnels from other different interchangers or time frequency signal source in interchanger.
The interchanger 2 realizes the function that optical fiber link is stablized and time frequency signal routing is automatically switched, and theory structure is such as
Shown in Fig. 2, when solving wavelength division multiplexer 12, the first optical fiber link time delay observing and controlling receiver 13, first by first annular device 11, first
Frequency signal receiver 14, control mainboard 15, RF switch 150, photoswitch 1500, the first optical fiber link time delay observing and controlling transmitter
16, the first time frequency signal transmitter 17, the first wavelength division multiplexer 18, the second circulator 19, third circulator 110, the second demultiplex
Division multiplexer 120, the second optical fiber link time delay observing and controlling receiver 130, the second time frequency signal receiver 140, the second optical fiber link
Time delay observing and controlling transmitter 160, the second time frequency signal transmitter 170, the second wavelength division multiplexer 180, fourth annular device 190 form.
Its connection relation is as follows：The second port 112 of first annular device 11 is connected with the first input optical signal of interchanger, third end
Mouth 113 is connected with the input ports of the first solution wavelength division multiplexer 12；The output port of first solution wavelength division multiplexer 12 is divided into two classes,
The first kind is the port 121 for the optical wavelength that wavelength is used to transmit optical fiber link time delay observing and controlling desired signal, this section ports and the
The input port of one optical-fiber time-delay observing and controlling receiver 13 is connected, and the second class is wavelength for transmitting time frequency signal and identification information
The port 122 of optical wavelength, this section ports are connected with the input port of the first time frequency signal receiver 14；When the first optical fiber link
The return optical output port for prolonging observing and controlling receiver 13 is connected with the first port 111 of first annular device 11；First time frequency signal connects
The microwave time frequency signal output port 141 of receipts machine 14 is connected with the first input port 1501 of RF switch 150, light wave time-frequency
Signal output port 142 is connected with the first input port 15004 of photoswitch 1500, identification information output port 143 and master
The first input port 151 for controlling plate 15 is connected；Other two input port 153,154 of master control borad 15 respectively with the first optical fiber chain
Road time delay observing and controlling transmitter 16 is connected with the delay measurements output port of the second optical fiber link time delay observing and controlling transmitter 160, and
The routing control signals output port 155 of master control borad 15 and 156 control signals with photoswitch 1500 and RF switch 150 respectively
Input port 15006 is connected with 1503, and the identification information output port 157,158 of master control borad 15 is sent out with the first time frequency signal respectively
It penetrates machine 17 with the identification information input port of the second time frequency signal transmitter 170 to be connected, the time frequency signal first of RF switch 150
With second output terminal mouth 1504,1505 respectively with the first time frequency signal transmitter 17 and the second time frequency signal transmitter 170 when
Frequency signal input port is connected, and third output port 1506 is then as the microwave time frequency signal output port of the interchanger, light
The first and second output port of time frequency signal 15001,15002 of switch 1500 respectively with the first time frequency signal transmitter 17 and
The light wave time frequency signal input port of two time frequency signal transmitters 170 is connected, and the third output port 15003 of photoswitch 1500 is then
Light wave time frequency signal output port as the interchanger；First optical fiber link time delay observing and controlling transmitter 16 and the first time frequency signal
The output port of transmitter 17 is connected with the input port of the first wavelength division multiplexer 18 respectively, the output of the first wavelength division multiplexer 18
Port is connected with the first port 191 of the second circulator 19, when the third port 193 and the first optical fiber link of the second circulator 19
The return light input port for prolonging observing and controlling transmitter 16 is connected, the second port 192 of the second circulator 19 as the interchanger the
One channel light signal output end mouth.The second port 1102 of third circulator 110 is connected with the second input optical signal of interchanger,
Its third port 1103 is connected with the input port of the second solution wavelength division multiplexer 120；The output end of second solution wavelength division multiplexer 120
Mouth is divided into two classes, and the first kind is the port 1201 for the optical wavelength that wavelength is used to transmit optical fiber link time delay observing and controlling desired signal, this
Section ports are connected with the input port of the second optical-fiber time-delay observing and controlling receiver 130, and the second class is wavelength for transmitting time-frequency letter
Number and identification information optical wavelength port 1202, the input port phase of this section ports and the second time frequency signal receiver 140
Even；The first port 1101 of the return optical output port and third circulator 110 of second optical fiber link time delay observing and controlling receiver 130
It is connected；Second input terminal of the microwave time frequency signal output port 1401 and RF switch 150 of the second time frequency signal receiver 140
Mouth 1502 is connected, and light wave time frequency signal output port 1402 is connected with the second input port 15005 of photoswitch 1500, mark
Know information output mouth 1403 with the second input port 152 of master control borad 15 to be connected.Second optical fiber link time delay observing and controlling transmitter
160 and second the output port of time frequency signal transmitter 170 be connected respectively with the input port of the second wavelength division multiplexer 180,
The output port of two wavelength division multiplexers 180 is connected with the first port 1901 of fourth annular device 190, and the of fourth annular device 190
Three ports 1903 are connected with the return light input port of the second optical fiber link time delay observing and controlling transmitter 160, fourth annular device 190
Second channel light signal output end mouth of the second port 1902 as the interchanger.If interchanger need more multichannel when
It waits, optical fiber link time delay observing and controlling receiver, time frequency signal receiver, optical fiber link time delay can be increased according to above-mentioned connection type
Observing and controlling transmitter, time frequency signal transmitter, wavelength division multiplexer, solution wavelength division multiplexer and circulator are to increase optical signal input
Output channel.
The effect in the time frequency signal source 3 is that the High-precision Microwave time frequency signal that atomic clock generates is modulated to optical signal
On, or light clock is generated into high-precision light wave time frequency signal and is transmitted directly in the form of optical signal, theory structure such as Fig. 3 institutes
Show, by high precision clock 21, master control borad 22, RF switch 23, photoswitch 230, the first optical fiber link time delay observing and controlling transmitter 24,
First time frequency signal transmitter 25, the second optical fiber link time delay observing and controlling transmitter 26, the second time frequency signal transmitter 27, first wave
Division multiplexer 28, the second wavelength division multiplexer 29, first annular device 201, the second circulator 202 composition.Its connection relation is as follows：It is high
The optical frequency time frequency signal output port 211 of accuracy clock 21 is connected with the time-frequency input signal port 2301 of photoswitch 230, and light
The output signal port 2303 and 2304 of switch 230 is respectively as the third channel light signal output end mouth in time frequency signal source and
The microwave time frequency signal output port 212 of four-way light signal output end mouth 2015 and 2016, high precision clock 21 is opened with radio frequency
23 time frequency signal input port 231 is closed to be connected, two input ports 221,222 of master control borad 22 respectively with the first optical fiber link
Time delay observing and controlling transmitter 24 is connected with the delay measurements output port of the second optical fiber link time delay observing and controlling transmitter 26, and master control
232 phase of control signal input mouth of the microwave time frequency signal routing control signals output port 223 and RF switch 23 of plate 22
Even, the control signal input mouth of the light wave time frequency signal routing control signals output port 226 and photoswitch 230 of master control borad 22
2302 are connected, the identification information output port 224,225 of master control borad respectively with the first time frequency signal transmitter 25 and the second time-frequency
The identification information input port of signal transmitter 27 is connected, the first and second output port of time frequency signal 233 of RF switch 23,
234 microwave time frequency signal input port phases with the first time frequency signal transmitter 25 and the second time frequency signal transmitter 27 respectively
Even；The output port of first optical fiber link time delay observing and controlling transmitter 24 and the first time frequency signal transmitter 25 respectively with the first wavelength-division
The input port of multiplexer 28 is connected, the first port of the output port and first annular device 201 of the first wavelength division multiplexer 28
2011 are connected, and the third port 2013 of first annular device 201 and the return light of the first optical fiber link time delay observing and controlling transmitter 24 are defeated
Inbound port is connected, the first passage light signal output end of the second port 2012 of first annular device 201 as the time frequency signal source
Mouth 2012；The output port of second optical fiber link time delay observing and controlling transmitter 26 and the second time frequency signal transmitter 27 is respectively with second
The input port of wavelength division multiplexer 29 is connected, the first end of the output port of the second wavelength division multiplexer 29 and the second circulator 202
Mouth 2021 is connected, the return lights of the third port 2023 of the second circulator 202 and the second optical fiber link time delay observing and controlling transmitter 26
Input port is connected, and the second port 2022 of the second circulator 202 is exported as the second channel optical signal in the time frequency signal source
Port.If time frequency signal source needs more multichannel, optical fiber link time delay can be increased according to above-mentioned connection type and surveyed
Transmitter, time frequency signal transmitter, wavelength division multiplexer, circulator are controlled to increase optical signal output channel.
The embodiment of high-precision optical fiber network is as shown in figure 4, wherein include 4 interchangers 42,43,45,46 in the present invention
With 1 time frequency signal source 41, totally 5 network nodes.Time frequency signal source 1 sends out 10MHz frequency standard signals, and passes through light respectively
Fibre 410 and 411 is connected with interchanger 42 and 43, interchanger 42 again by optical fiber 421 and 422 respectively with interchanger 44 and 45 phases
Even, interchanger 43 is connected with interchanger 44 and 45 respectively by optical fiber 431 and 442, passes through optical fiber 441 between interchanger 44 and 45
It is connected, each switch network node passes through the different optical fiber in 3 tunnels and other 3 interchangers or time frequency signal in this way
Source connects.Wherein interchanger 42,43,44,45 and the theory structure in time frequency signal source 41 difference is as shown in Figures 2 and 3, and exchanges
The implementation principle structure of optical fiber link timing_delay estimation receiver in machine and time frequency signal source is as shown in Figure 5.The of circulator 51
Two-port netwerk 512 is connected with the optical signal for entering optical fiber link timing_delay estimation receiver, the third port 513 and demultiplex of circulator 51
The input port of division multiplexer 52 is connected, and solves two wavelength channel λ of wavelength division multiplexer 521、λ3Output port respectively with photoelectricity
Detector 53 is connected with 54, the microwave input port of the frequency output signal and DFB semiconductor laser 56 of photodetector 53
It is connected, the time output signal of photodetector 54 is connected with the microwave input port of acousto-optic modulator 57, and acousto-optic modulator
57 light input port is connected with DFB semiconductor laser 55, and the wavelength of DFB semiconductor laser 55 and 56 is respectively λ2、λ4,
The optical output port of acousto-optic modulator 57 and the optical output port of DFB semiconductor laser 56 respectively with wavelength division multiplexer 58 two
A input port is connected, and the output port of wavelength division multiplexer 58 is connected with the first port 511 of circulator 51.
The theory structure of the implementation of optical fiber link timing_delay estimation transmitter in the interchanger and time frequency signal source is such as
Shown in Fig. 6.The frequency signal that rubidium clock 61 is sent out first inputs power splitter 62, then the first output port and DFB of power splitter 62
The microwave input port of semiconductor laser 64 is connected, the second output terminal mouth of power splitter 62 and the first microwave of phase discriminator 696
Input port is connected；The 1pps time signals that rubidium clock 61 is sent out input power splitter 63, then the first output port of power splitter 63
It is connected with the microwave input port of acousto-optic modulator 66, and the light input port and DFB semiconductor laser of acousto-optic modulator 66
65 are connected, and the wavelength of DFB semiconductor laser 55 and 56 is respectively λ1、λ3, the second output terminal mouth and time interval of power splitter 63
The microwave input port of counter 697 is connected；The optical output port of acousto-optic modulator 66 and the light of DFB semiconductor laser 64 are defeated
Exit port is connected with two input ports of wavelength division multiplexer 67 respectively, output port and the circulator 68 of wavelength division multiplexer 67
First port 681 is connected, and the second port 682 of circulator 68 is connected with the light input port of fibre delay line 69；Circulator 68
Third port 683 be connected with the light input port of wavelength division multiplexer 693, two wavelength channel λ of wavelength division multiplexer 6932、λ4
Output port be connected respectively with photodetector 694 and 695, the frequency output signal of photodetector 694 and phase discriminator 696
The second microwave input port be connected, the 1pps time signals output signal of photodetector 695 and time-interval counter 697
The second microwave input port be connected；Two phase discrimination signal output ports of phase discriminator 696 respectively with PID circuit boards 691 and main
It controls plate 692 to be connected, the time interval counter value output port of time-interval counter 697 is connected with master control borad 692, then PID
The output port of circuit board 691 is connected with the electric signal input end mouth of fibre delay line, and the output port of master control borad is used as and is somebody's turn to do
The electric signal output port 602 of optical fiber link timing_delay estimation transmitter, while the optical output port of fibre delay line 69 is as light
The optical output port 601 of fine chain-circuit time delay control transmitter.Rubidium clock 61 generally has multichannel output in the present embodiment, in addition more
A optical fiber link timing_delay estimation transmitter can share a rubidium clock.
Optical fiber chain can be realized in optical fiber link timing_delay estimation transmitter and the matching use of optical fiber link timing_delay estimation receiver
The complete stability on road, and the time delay value of link is fed back to the master control borad of interchanger, for control RF switch, photoswitch, when
The other devices such as frequency signal transmitter, for example if larger shake or variation has occurred in the time delay of certain optical fiber all the way, lead
Control plate will send control signals to RF switch, photoswitch and two time frequency signal transmitters, make time frequency signal along with this
The in addition optical fiber transmission all the way of ground interchanger or the connection of time frequency signal source, to achieve the purpose that pretection switch.Its time delay is steady
Determine principle and can refer to document：F.Yang,D.Xu,Q.Liu,et al..“Accurate transmission of time and
frequency signals over optical fibers based on WDM and two way optical
compensation techniques”,CLEO:Science and Innovations,California,CA,USA,
JTu4A.99,2013.Such as in the present embodiment with this solution implement after, each optical fiber 410,411,421,422,431,
441,442 it can be all in stable state, time delay will not be influenced by environmental changes such as temperature, vibrations.
Master control borad other than being routed according to the time delay value of feedback control switch, can also clock synchronization keep pouring in it is defeated each
Item identification information, such as propagation delay time value, the calibration of equipment fixed delay, phase error, the interchanger number of process, routing ground
The every terms of information such as location, hardware device state information are handled, to realize the optimum management to whole network.
The main function of the time frequency signal receiver in interchanger and time frequency signal source is to realize that time frequency signal is being handed over simultaneously
Change planes or time frequency signal source in routing management and control microwave time frequency signal is needed first to carry out it opto-electronic conversion, it is then defeated
Enter RF switch and control its route direction will pass through master control borad, and for light wave time frequency signal, does not need opto-electronic conversion, it can be with
It is directly entered photoswitch and controls its route direction will pass through master control borad.Time frequency signal receiver implementation principle knot in the embodiment
Shown in structure such as Fig. 7 (a), the light wave for carrying microwave time frequency signal to be passed enters photodetector 71, when then exporting microwave to be passed
Frequency signal, and the light wave for carrying id signal to be passed enters photodetector 72, then output identification signal, id signal include
The relevant informations such as telephone net node information, complete Delay that the time frequency signal passes through.If in time frequency signal including light
Wave time frequency signal, then time frequency signal receiver should increase light wave channel, as shown in Fig. 7 (b).
In addition the main function of the time frequency signal transmitter in interchanger and time frequency signal source is to realize that time frequency signal is being handed over
Change planes or time frequency signal source in route transmission and relaying amplify.Time frequency signal transmitter implementation principle structure in the embodiment
As shown in Fig. 8 (a), the microwave time frequency signal of input is directly modulated on low noise laser 81, and identification information is modulated to ether
In net transmitting optical transmitter module 82, subsequently into the output wavelength division multiplexer of interchanger, to form output optical signal.If when
Include light wave time frequency signal in frequency signal, then time frequency signal transmitter should increase light wave channel, as shown in Fig. 8 (b), such as
Fruit transmission range is longer, then in order to realize the relaying amplification of lightwave signal, low noise image intensifer 83 should also be added, such as Fig. 8
(c) shown in.
Claims (2)
1. a kind of high-precision optical fiber time frequency signal synchronizing network, including optical fiber (1), N number of interchanger (2), M time frequency signal source
(3), wherein N is 2 or more positive integer, and the positive integer that M is 1 or more, each interchanger and time frequency signal source are a networks
Node, forms N+M network node in total, and connection relation is as follows：Each time frequency signal source in the M time frequency signal source
It is connect by optical fiber with two adjacent interchangers, each interchanger is different by least three tunnels in N number of interchanger
Optical fiber is connected from other different interchangers or time frequency signal source, which is characterized in that the effect in the time frequency signal source (3)
It is that the High-precision Microwave time frequency signal that atomic clock generates is modulated on optical signal, or light clock is generated high-precision light wave time-frequency letter
It transmits number directly in the form of optical signal, the time frequency signal source (3) includes high precision clock (21), master control borad (22), penetrates
Frequency switch (23), photoswitch (230), the first optical fiber link time delay observing and controlling transmitter (24), the first time frequency signal transmitter (25),
Second optical fiber link time delay observing and controlling transmitter (26), the second time frequency signal transmitter (27), the first wavelength division multiplexer (28), second
Wavelength division multiplexer (29), first annular device (201) and second ring device composition (202), connection relation is as follows：The high-precision
The optical frequency time frequency signal output port (211) of clock (21) is connected with the time-frequency input signal port (2301) of photoswitch (230),
The output signal port (2303) of photoswitch (230) and (2304) are respectively the third channel light signal output end in time frequency signal source
Mouth and fourth lane light signal output end mouth；
The microwave time frequency signal output port (212) of high precision clock (21) and the radio frequency time-frequency of the RF switch (23) are believed
Number input port (231) is connected, the first output port of time frequency signal (233) and second output terminal of the RF switch (23)
Mouth (234) is inputted with the microwave time frequency signal of the first time frequency signal transmitter (25) and the second time frequency signal transmitter (27) respectively
Port is connected；
The first input port (221) of the master control borad (22), the second input port (222) respectively with the first optical fiber link when
The output port of the output port and the second optical fiber link time delay observing and controlling transmitter (26) that prolong observing and controlling transmitter (24) is connected, master control
The microwave time frequency signal output port (223) of plate (22) is connected with the control port (232) of RF switch (23), master control borad (22)
Light wave time frequency signal output port (226) be connected with the control port (2302) of photoswitch (230), the first identifier of master control borad
Information output mouth (224), second identifier information output mouth (225) mark with the first time frequency signal transmitter (25) respectively
Information input port is connected with the identification information input port of the second time frequency signal transmitter (27)；First optical fiber link time delay is surveyed
The output port of the output port and the first time frequency signal transmitter (25) of controlling transmitter (24) distinguishes the first wavelength division multiplexer
(28) input terminal is connected, the output end of the first wavelength division multiplexer (28) and the first port (2011) of first annular device (201)
It is connected, the return light of the third port (2013) of first annular device (201) and the first optical fiber link time delay observing and controlling transmitter (24)
Input port is connected, and the second port (2012) of first annular device (201) is defeated for the first passage optical signal in the time frequency signal source
Exit port；
The output end of the output port of second optical fiber link time delay observing and controlling transmitter (26) and the second time frequency signal transmitter (27)
Mouth is connected with the input port of the second wavelength division multiplexer (29) respectively, the output port and the second ring of the second wavelength division multiplexer (29)
The first port (2021) of shape device (202) is connected, when the third port (2023) of the second circulator (202) is with the second optical fiber link
The return light input port for prolonging observing and controlling transmitter (26) is connected, and the second port (2022) of the second circulator (202) is the time-frequency
The second channel light signal output end mouth of signal source.
2. high-precision optical fiber time frequency signal synchronizing network according to claim 1, it is characterised in that the interchanger (2)
Realize optical fiber link stablize and time frequency signal routing optimality selection function, the interchanger (2) by first annular device (11),
First solution wavelength division multiplexer (12), the first optical fiber link time delay observing and controlling receiver (13), the first time frequency signal receiver (14), master
Control plate (15), RF switch (150), photoswitch (1500), the first optical fiber link time delay observing and controlling transmitter (16), the first time-frequency letter
Number transmitter (17), the first wavelength division multiplexer (18), the second circulator (19), third circulator (110), the second solution wavelength-division multiplex
Device (120), the second optical fiber link time delay observing and controlling receiver (130), the second time frequency signal receiver (140), the second optical fiber link
Time delay observing and controlling transmitter (160), the second time frequency signal transmitter (170), the second wavelength division multiplexer (180) and fourth annular device
(190) it forms, connection relation is as follows：
The second port (112) of first annular device (11) is the first optical signal input mouth, the third end of first annular device (11)
Mouth (113) is connected with the input port of the first solution wavelength division multiplexer (12)；The output port point of first solution wavelength division multiplexer (12)
Not with the first optical fiber link time delay observing and controlling receiver（13）Input port, the first time frequency signal receiver (14) input port
It is connected, the output port of the first optical fiber link time delay observing and controlling receiver (13) and the first port (111) of first annular device (11)
It is connected；The microwave time frequency signal output port (141) of first time frequency signal receiver (14) and the RF switch (150)
First input port (1501) is connected, the light wave time frequency signal output port of the first time frequency signal receiver (14)
(142) it is connected with the first input port (15004) of the photoswitch (1500), the first time frequency signal receiver
(14) identification information output port (143) is connected with the first input port (151) of the master control borad (15)；Master control borad
(15) the second input port (153), third input port (154) respectively with the first optical fiber link time delay observing and controlling transmitter (16)
Output port and the second optical fiber link time delay observing and controlling transmitter (160) output port be connected, master control borad（15）Routing control
Signal output port (155) processed and (156) are opened with the control signal input mouth of photoswitch (1500) (15006) and radio frequency respectively
The control signal input mouth (1503) for closing (150) is connected, the identification information output port (157) of master control borad (15), (158) point
It is not connected with the identification information input port of the first time frequency signal transmitter (17) and the second time frequency signal transmitter (170), penetrates
Frequency switch (150) the first output port of time frequency signal (1504) and second output terminal mouth (1505) respectively with the first time frequency signal
Transmitter (17) is connected with the time frequency signal input port of the second time frequency signal transmitter (170), the time-frequency of RF switch (150)
Signal third output port (1506) is the microwave time frequency signal output port of the interchanger, the time frequency signal of photoswitch (1500)
First output port (15001) and second output terminal mouth (15002) respectively with the first time frequency signal transmitter (17) and second when
The light wave time frequency signal input port of frequency signal transmitter (170) is connected, the third output port (15003) of photoswitch (1500)
It is the light wave time frequency signal output port of the interchanger；First optical fiber link time delay observing and controlling transmitter (16) and the first time frequency signal
The output port of transmitter (17) is connected with the input port of the first wavelength division multiplexer (18) respectively, the first wavelength division multiplexer (18)
Output port be connected with the first port (191) of the second circulator (19), the third port (193) of the second circulator (19) with
The return light input port of first optical fiber link time delay observing and controlling transmitter (16) is connected, the second port of the second circulator (19)
(192) it is the first passage light signal output end mouth of the interchanger；
The second port (1102) of third circulator (110) is the second optical signal input mouth, the third of third circulator (110)
Port (1103) is connected with the input port of the second solution wavelength division multiplexer (120)；The output port of second wavelength division multiplexer (120)
It is divided into two classes, the first kind is the port (1201) for the optical wavelength that wavelength is used to transmit optical fiber link time delay observing and controlling desired signal, this
Section ports are connected with the input port of the second optical-fiber time-delay observing and controlling receiver (130), and the second class is wavelength for transmitting time-frequency
The port (1202) of the optical wavelength of signal and identification information, the input of this section ports and the second time frequency signal receiver (140)
Port is connected；The of the return optical output port of second optical fiber link time delay observing and controlling receiver (130) and third circulator (110)
Single port (1101) is connected；The microwave time frequency signal output port (1401) of second time frequency signal receiver (140) is opened with radio frequency
The second input port (1502) for closing (150) is connected, light wave time frequency signal output port (1402) and photoswitch (1500)
Second input port (15005) is connected, the second input port of identification information output port (1403) and master control borad (15)
(152) it is connected；The output port of second optical fiber link time delay observing and controlling transmitter (160) and the second time frequency signal transmitter (170)
It is connected respectively with the input port of the second wavelength division multiplexer (180), the output port of the second wavelength division multiplexer (180) and Fourth Ring
The first port (1901) of shape device (190) is connected, when the third port (1903) of fourth annular device (190) is with the second optical fiber link
The return light input port for prolonging observing and controlling transmitter (160) is connected, and the second port (1902) of fourth annular device (190) is the exchange
The second channel light signal output end mouth of machine.
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103620991A (en) * | 2011-05-06 | 2014-03-05 | Fts电脑技术有限公司 | Network and method for implementing a high-availability grand master clock |
| CN104320238A (en) * | 2014-10-21 | 2015-01-28 | 浙江大学 | Seafloor observation network time synchronization method under large traffic background |
| CN104683089A (en) * | 2014-12-03 | 2015-06-03 | 国家电网公司 | Time frequency synchronization fusion network architecture |
| CN104980222A (en) * | 2015-07-16 | 2015-10-14 | 北京邮电大学 | Time transfer device and method |
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| CN104954093B (en) * | 2015-06-29 | 2017-07-04 | 北京无线电计量测试研究所 | A kind of High Precision Long-distance Time Transmission system and method based on optical fiber |
| CN105591697B (en) * | 2016-01-20 | 2018-04-17 | 中国科学院上海光学精密机械研究所 | High-precision optical fiber time-frequency annular networking system and network-building method |
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| CN103620991A (en) * | 2011-05-06 | 2014-03-05 | Fts电脑技术有限公司 | Network and method for implementing a high-availability grand master clock |
| CN104320238A (en) * | 2014-10-21 | 2015-01-28 | 浙江大学 | Seafloor observation network time synchronization method under large traffic background |
| CN104683089A (en) * | 2014-12-03 | 2015-06-03 | 国家电网公司 | Time frequency synchronization fusion network architecture |
| CN104980222A (en) * | 2015-07-16 | 2015-10-14 | 北京邮电大学 | Time transfer device and method |
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