CN1093846A - Fiber optic cable monhoring system - Google Patents
Fiber optic cable monhoring system Download PDFInfo
- Publication number
- CN1093846A CN1093846A CN93104451A CN93104451A CN1093846A CN 1093846 A CN1093846 A CN 1093846A CN 93104451 A CN93104451 A CN 93104451A CN 93104451 A CN93104451 A CN 93104451A CN 1093846 A CN1093846 A CN 1093846A
- Authority
- CN
- China
- Prior art keywords
- signal
- moisture content
- optical fiber
- optical
- signal generator
- 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
- Investigating Or Analysing Materials By Optical Means (AREA)
Abstract
The method and system of monitoring optical fiber communication cable state.Utilize two lasing light emitters and monitor attenuated optical signal on two kinds of different wave lengths simultaneously, to determine, to analyze the machine performance of cable arrangement.A specific detectors sign indicating number is all specified in each joint, and by water content detection, sensor drive light joint detector, this transducer are a water excitation battery sensor.The moisture that enters monitored adapter piece soaks take-up strap, and stimulus sensor produces enough electric energy and promotes timing, code generator and modulation circuit in the detector cell.At the modulated light signal of device end monitoring, and the position of the decoded Alarm Detector of addressing.
Description
The present invention relates to the monitoring of telecommunication cable, relate more specifically to the monitoring of optical fiber communication cable.
Phone and some other telecommunication cables will stand environment and the people is damage and the abrasion that cause.Can damage the cable of exposure such as bad weather environment such as strong wind, ice and snow, rainwater mighty torrent and thunders and lightnings.Building or destruction near harm may come from.It is a main cause that causes service disruption (broken string) that rainwater or underground water immerse in impaired part cable core or the adapter piece.Therefore, people have made the state that various effort keep cable to be in being in good repair, and anti-sealing enters among the construction of cable.
Frequently, damage does not cause the forfeiture of service immediately, but causes cable system slowly to degenerate, and this slowly degenerating usually causes cable failure and service disruption.Then must under very urgent situation, carry out its reparation later.This very high rehabilitation expense of will paying wages on the one hand also causes the loss on the income on the one hand.
Begin till now from first leader cable equipment, using some to safeguard that monitoring system is to provide the early warning of cable fault.Time that this makes people to be ranked to safeguard and avoid losing service and expensive reparation.The earliest system uses air pressure to prevent water breakthrough cable or adapter piece, and comes detection failure by the air velocity that measurement enters the cross-section of cable.
Modern telephone cable comprises fibre-optic cable, is usually filled by the water proof mixture, flows among the cable core to prevent water.Though provide good resistance for the water enchroachment (invasion) evil, the composition of filling also stops or has seriously limited flowing of air, thereby makes the air pressure monitoring system become useless.In order to overcome this restriction, and safeguard monitoring, developed some all-electronic systems, as 5,077, No. 526 described those systems of United States Patent (USP) of people such as people's such as McNaughton No. 4,480,251, United States Patent (USP) and Vokey for the telephone cable that is filled provides.
Be the fibre-optic cable that is configured under some applicable cases, comprise that fibre-optic cable all adopts dielectric insulation material as the situation in overhead electric power transfer fixing cord or the low phase electric conductor (below phase conduc-tors) of the suspension type on launching tower.Therefore, those are just no longer suitable such as the described traditional cable of metallic conductance body component and the joint monitoring method of needing of people's patents such as people such as McNaughton and Vokey.
The OTDR technology has been used to monitor optical cable and joint, and this technology is injected optical fiber with light pulse, measures the energy of reflection again, to measure increasing of energy loss.These method costs are very high, and need be in adapter piece the specified moisture of detection fiber bending apparatus, to attempt to monitor the immersion of water, in addition, the characteristic of joint bending apparatus always can not expect, and must accurately know the definite optical distance to each joint.Although preferably can adopt active checkout gear at the tap points place, the main difficulty that exists is for all dielectric cable, does not have practical means to provide power supply to operate these devices to the joint.
The present invention is directed to the problems referred to above and propose, it provides the damage of the monitoring construction of cable and adapter piece or the mechanism that moisture is invaded in every respect.
According to an aspect of the present invention, provide a moisture content detection signal generator, it comprises:
Moisture content acquisition sensor device produces voltage in order to respond this sensor device with contacting of water; An automatically controlled coded signal generating means that is electrically connected with this sensor device is in order to produce a fault-signal according to the electric energy from sensor device that receives; And the light modulator device that is electrically connected with this coded signal generating means, produce the optical signalling of coding in order to the appearance of response fault-signal.
A this respect of the present invention provides a self-contained mechanism, in order to survey entering of joint moisture content, sends the signal that moisture content enters along optical fiber.Preferable moisture content acquisition sensor device is a band, and it contains the herring bone of two different metals that are embedded in the permeable insulator and separated by water-soluble ionize solid.This band can be wrapped in around the joint.When water contacts with the ionize solid, produce a kind of electrolyte, this transducer becomes the voltaic cell of driving signal generator.
According to a further aspect in the invention, provide a light joint detector cell, in order to send the signal that moisture penetration contains the adapter piece of two fiber cable joint ends, this detector cell comprises:
Piecing devices in adapter piece are in order to keep the aligning of the optic fibre end of optical cable separately;
Mobile device is in order to the optic fibre end skew of one of optical fiber end of making a cable selectively with respect to another root cable of correspondence;
The signal generation apparatus that is connected with this mobile device is in order to drive this mobile device selectively; And
The moisture content detector means, the appearance of moisture content is to drive this signal generation apparatus in the response adapter piece.
Mobile device plays the effect of optical modulator, and the light signal that is transmitted on the monitored optical fiber is modulated.Preferably, this signal generation apparatus comes modulation signal according to a sign indicating number that has only this signal generator just to have.So just can directly pick out the joint that has been penetrated by moisture content.
According to a further aspect in the invention, provide a fiber optic cable monhoring system, in order to monitor at least one physical condition with optical fiber of first and second terminations, this system comprises:
The optical signal transmitter device is monitored light signals in order to produce two with different wavelength, and this monitor signal is transmitted among first termination of optical fiber;
The optical receiver device is connected with second termination of optical fiber, optically in order to receive described monitor signal; And
Signal processing apparatus is in order to separate described monitor signal and to measure their amplitude.
The state of cable has been represented in the decay of signal.For example, for the signal that wavelength is 1300nm and 1550nm, similar decay can be thought what microbend (microbending) caused on two kinds of wavelength.Microbend may be that the variation owing to cable extruding or the cable configuration relevant with temperature causes.Significantly decay at 1550nm wavelength place increase then can only be relevant with macrobending (macrobending), this normally owing to optical cable tangle or losing of optical fiber causes.
Light signal preferably obtains modulation with some selected frequencies.When receiving, these composite signals are converted into a signal of telecommunication, and this signal of telecommunication is filtered and be separated into two signals then.
Light signal can utilize two lasers to produce, and distributes to a lot of optical fiber.Each optical fiber is monitored by different receivers then, and the output of receiver is then scanned by a multiplexer, and the output of this multiplexer offers traditional monitoring alarm unit.
The further aspect according to the present invention provides a kind of method of monitoring optical fiber, and it comprises:
Along optical fiber from a terminal to a receiving terminal with two light signals of different wavelength emission;
Monitor this two signals at receiving terminal;
Measure the decay of two signals; And
When exceeding, determined decay produces alarm when a predetermined maximum allows pad value.
Below in conjunction with accompanying drawing these aspects of the present invention will be described in further detail.
Fig. 1 is the schematic diagram according to monitoring system of the present invention;
Fig. 2 is the schematic diagram of fiber optic emitter;
Fig. 3 is the schematic diagram of photodetector unit;
Fig. 4 is the profile of a joint;
Fig. 5 is the profile of moisture acquisition sensor device;
Fig. 6 is the curve chart of expression optical fiber splice coupling loss with respect to the optic fibre end skew;
Fig. 7 is the schematic diagram of optical receiver;
Fig. 8 is the schematic diagram of an alternative embodiment of photodetector unit;
Fig. 9 is the curve chart of expression optical fiber splice coupling loss with respect to the optic fibre end axial separation.
Referring to accompanying drawing, particularly Fig. 1 shows a fiber optic cable monhoring system 10 that is associated with fibre-optic cable 12.Shown optical cable is unit mould (sm) optical cable, and its length is up to 100Km.Shown optical cable comprises one along 14 parts of the joint on its length direction.Usually, a complete cable can comprise a lot of joints.This optical cable comprises a lot of root optical fiber 16.
Receiving terminal at optical fiber is an optical receiver 20(Fig. 7), it detects the laser that intercepts on the diode 42 and detect from each monitored optical fiber at a PIN, and described light converts the signal of telecommunication to by diode, and this signal of telecommunication is amplified by preamplifier 44.This signal of telecommunication comprises frequency content F1 and F2, and they are by band pass filter 46 and 50 separated coming, and measured circuit 48 and 52 is measured.Calculate the optical attenuation of fiber lengths on two wavelength by the amplitude of measuring.
Optical receiver also comprises a pulse detector 54, in order to monitor the pulse that produces in the photodetector unit.This photodetector unit will be described in more detail in the back.
The output of optical receiver is sent to multiplexer 56, and the latter is scanned the output from each monitored optical fiber, and provides input to central office's terminal 58; Central office's terminal 58 comprises warning circuit 58, gives the alarm when exceeding a predetermined maximum attenuation at detected optical fiber attenuation.This terminal also comprises a decoding circuit 60, in order to deciphering from the pulse of pulse detector 54.
Referring to Fig. 3,4 and 5, joint 14 comprises a modulator 62 especially, is used for producing pulse at the light by each optical fiber emission and detects for pulse detector 54.Modulator comprises a joint 64 that has V-type groove 66, and V-type groove 66 makes by the termination of the monitored optical fiber of cable joint and aimed at.In the joint, optic fibre end 70 has a very little ferrous metal element 72 that is connected in its end face.It is positioned under the utmost point of being close to modulator electromagnet 74.This ferromagnet 74 electrically is connected between the collector electrode 78 of moisture content acquisition sensor 76 and driving transistors 80.The emitter of this transistor 80 is connected in moisture content acquisition sensor 76 its base stages 84 and then is connected in code generator 86, and the latter is connected to clock 88 again.Code generator all strides across the terminal of moisture acquisition sensor 76 with clock and is connected.
With 5 to 10 microns energy needed of 125 microns glass fibre deflection is considerably less.These detector circuits are designed to adopt low-voltage microwatt CMOS integrated circuit.As a result, one meter long single-sensor battery can be to modulator and relevant several weeks of some circuit supplies.Thereby guaranteed detection to wet joint.
As previously mentioned, optical receiver intercepts and detects the laser from monitored optical fiber, and converts thereof into a signal of telecommunication.Decoded in decoding circuit by the pulse that pulse detector 54 detects, to distinguish the adapter piece that pulse occurs.Be a little purposes, will produce an exclusive pulse signal for the code generator 86 of each adapter piece.
Optical attenuation on the whole optical fiber under two kinds of monitor signal wavelength is to calculate by the amplitude of each switching electrical signals of measuring.Any over proof additional optical fiber decay all obtains analyzing.
Increase if record similar decay under two kinds of wavelength, so this decay increases can be thought to be caused by microbend, and it may be because cable extruding or cause with the construction of cable change of temperature correlation.Increase if only detect tangible decay under 1550nm, problem then may be relevant with macrobending, this normally owing to cable tangle or losing of optical fiber causes.
An alternative embodiment of photodetector is shown in Fig. 8.This embodiment is different from part embodiment illustrated in fig. 3 and is that modulator has adopted the joint 100 of capillary type, and in this joint, optic fibre end is aimed in sleeve pipe 102.Optical fiber one end 104 is fixing, and the other end is movable but apply bias voltage by spring to stiff end.An iron class sleeve pipe 108 is fixed on the movable end of optical fiber.Modulator coil 110 is around the optical fiber of adjacency sleeve pipe 108.When being excited, coil detaches optic fibre end 104 with optic fibre end 106, so just the signal on the optical fiber is modulated.
The curve that coupling loss is separated with respect to the axial optical fiber termination is provided by Fig. 9.Fibre movement is carried out with a kind of like this amplitude level, promptly greater than producing same coupling loss, needed skew.
Modulator and relevant electricity and mechanical organ may be not easy to be installed among the joint carriage or other adapter assembly that is used in the adapter piece, can utilize the appropriate location of the carriage back side or side so.
Although more than described one embodiment of the present of invention, it will be appreciated that, can also make some other embodiment within the scope of the invention.Therefore, for example, the photodetector unit can adopt some non-modulators as the electromagnetic type shown in the figure.For example, can electric pulse be changed into mechanical bias and follow-up coupling attenuation with piezoelectric crystal or some other dynamo-electric modulating device.Any other device that plays the optical switch effect all can adopt.The moisture content acquisition sensor can be made by any two kinds of metals of selecting, as long as provide half suitable cell reaction under the situation that suitable electrolyte exists.Therefore be to be understood that, can not think that the present invention is only limited to disclosed specific embodiment.The present invention is only limited by appending claims.
Claims (30)
1, a kind of moisture content detection signal generator comprises:
Moisture content acquisition sensor device produces voltage in order to respond this sensor device with contacting of water; An automatically controlled coded signal generating means that is electrically connected with this sensor device is in order to produce fault-signal according to the electric energy that receives from transducer; And the light modulator device that is electrically connected with this coded signal generating means, produce the optical signalling of coding in order to the appearance of response fault-signal.
2,, wherein survey the moisture sensor device and also comprise water-soluble ionize solid between two kinds of metal partss and two metal partss according to the signal generator of claim 1.
3,, also be included in the permeable electric insulation arrangement between ionize solid and the every kind of metal parts according to the signal generator of claim 2.
4, according to the signal generator of claim 3, wherein each metal parts comprises an elongated band that is embedded among the permeable electrical insulating material.
5, according to the signal generator of claim 4, wherein metal parts and ionize solid comprise a moisture content surveying tape.
6, according to the signal generator of claim 5, wherein one of metal parts is a magnesium, and another metal parts is a copper, and the ionize solid is a copper sulphate.
7, according to the signal generator of claim 1, wherein the coded signal generating means comprises the device that is used to produce the signal of telecommunication.
8, according to the signal generator of claim 7, wherein the coded signal generating means comprises the device that is used to produce pulse electrical signal.
9, a kind ofly be used for sending the light joint detector cell of signal that moisture content infiltrates the adapter piece of the tip side that comprises two optical cables, it comprises:
Piecing devices in adapter piece are used to keep the aligning of the optic fibre end of optical cable separately;
Mobile device is in order to the optic fibre end skew of one of optical fiber end of making a cable selectively with respect to another cable of correspondence;
With the signal generation apparatus that this mobile device is connected, be used for driving selectively this mobile device; And
The moisture content detector means drives described signal generator unit according to the appearance of moisture content in the adapter piece.
10, according to the detector cell of claim 9, wherein the moisture content detector means comprises a moisture content acquisition sensor device, produces voltage with contacting of water in order to respond this sensor device.
11, according to the detector cell of claim 10, wherein the moisture content checkout gear comprises that is wound in a piecing devices extension band on every side.
12, according to the detector cell of claim 11, wherein the moisture content checkout gear comprises two metal partss of separating that roughly extend along the length direction of being with, and the water-soluble ionize solid between two metal partss.
13, according to the detector cell of claim 9, wherein signal generation apparatus comprises the device that is used to produce coded electrical signal.
14, according to the detector cell of claim 13, wherein mobile device comprises the magnetic part that is coupled with described optical fiber one end and adjacent to this magnetic part and the electromagnet that is electrically connected with this signal generator.
15, a kind of fiber optic cable monhoring system is used to monitor the physical state that at least one has the optical fiber of first and second terminations, and this system comprises:
The optical signal transmitter device in order to producing two different monitor signals of wavelength, and is transmitted into this monitor signal first termination of optical fiber;
Optical receiver device with second termination of optical fiber is connected is used to receive this monitor signal; And
Signal processing apparatus is used for the separating monitoring signal and measures their amplitude.
16, according to the monitoring system of claim 15, wherein the optical signal transmitter device comprises the device that is used for the unlike signal frequency monitor signal being carried out amplitude modulation.
17, according to the monitoring system of claim 16, wherein the optical receiver device comprises the device that is used for the light detection conversion of signals is become to have the signal of telecommunication of corresponding signal frequency.
18, according to the monitoring system of claim 17, wherein electro-optical device comprises frequency discriminator, in order to separate this two signals of telecommunication.
19, according to the monitoring system of claim 15, wherein the optical signal transmitter device comprises coupler device, in order to monitor signal equally is transmitted into first termination of a plurality of optical fiber; The optical receiver device comprises a plurality of optical receivers, and each optical receiver is connected with second termination of a corresponding optical fiber, to receive monitor signal.
20, according to the monitoring system of claim 19, wherein signal processing apparatus comprises a plurality of processors, and each processor operatively is connected with a corresponding receiver, in order to handle the monitor signal by an optical fiber emission of correspondence.
21, according to the monitoring system of claim 20, also comprise the multiplexed apparatus that is connected with each processor, be used to scan the output of from processor.
22, according to the monitoring system of claim 21, also comprise joint at least one described optical fiber and the moisture content detection signal generator that is associated with described joint, the moisture content that is used to respond the joint of detection is modulated monitor signal.
23, according to the monitoring system of claim 22, its center tap also comprises the piecing devices that two pigtail fiber terminations are aimed at; And moisture content detection signal generator comprises modem devices, is used to cause at least one described pigtail fiber termination to lose with another termination and aims at; And code generating device, be used to operate another termination is passed in the modem devices modulation from a termination of described optical fiber light signal.
24, according to the monitoring system of claim 23, wherein moisture content detection signal generator comprises moisture content acquisition sensor device, is used to respond this transducer and produces voltage with contacting of water; The automatically controlled coded signal generating means that is electrically connected with this sensor device is used for producing a fault-signal according to the electric energy from sensor device that receives; The modem devices that can respond the generation of described fault-signal and work.
25, according to the monitoring system of claim 22, its center tap comprises the piecing devices that two pigtail fiber terminations are aimed at; Moisture content detection signal generator comprises modem devices, is used for axially separating joint optic fibre end; Code generating device is used to operate another termination is passed in the modem devices modulation from a termination of described optical fiber light signal.
26, according to the monitoring system of claim 25, wherein moisture content detection signal generator comprises moisture content acquisition sensor device, is used to respond this transducer and produces voltage with contacting of water; The automatically controlled coded signal generating means that is electrically connected with this sensor device is in order to produce a fault-signal according to the electric energy from this transducer that receives; Modulating device can respond described fault-signal and produce and work.
27, according to the monitoring system of claim 17, in described optical fiber, comprise a plurality of joints and a plurality of moisture content detection signal generating meanss that are associated with corresponding joint, use the moisture content that detects in response to the corresponding joints place and modulate monitor signal, each moisture content detection signal generator comprises the device that is used for the modulation monitor signal of the modulation system that is different from other moisture content detection signal generator.
28, the method for monitoring optical fiber comprises:
Launch two light signals along optical fiber from a terminal to a receiving terminal with different wavelength;
Monitor this two signals at receiving terminal;
Detect the decay of two signals; And
When exceeding, survey decay produces an alarm signal when a predetermined maximum allows pad value.
29,, also comprise the alarm signal that produces the expression fiber optic microbend according to the decay of two signals according to the method for claim 28.
30,, also comprise the only alarm signal of the generation of the decay in having the signal of longer wavelength expression optical fiber macrobending of basis according to the method for claim 29.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN93104451A CN1046830C (en) | 1993-04-14 | 1993-04-14 | Fiber optic cable monhoring system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN93104451A CN1046830C (en) | 1993-04-14 | 1993-04-14 | Fiber optic cable monhoring system |
Related Child Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN99105287A Division CN1236234A (en) | 1999-04-30 | 1999-04-30 | Fiber optic cable monitoring system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1093846A true CN1093846A (en) | 1994-10-19 |
| CN1046830C CN1046830C (en) | 1999-11-24 |
Family
ID=4985197
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN93104451A Expired - Fee Related CN1046830C (en) | 1993-04-14 | 1993-04-14 | Fiber optic cable monhoring system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN1046830C (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100472207C (en) * | 2004-08-16 | 2009-03-25 | 日本电气株式会社 | Moisture detection label, moisture detection device, moisture detection method, power shutoff method, and electronics device |
| CN100546225C (en) * | 2003-07-28 | 2009-09-30 | 爱默生电气公司 | The method and apparatus that is used for the optical receiver of low intensity optical communication with the fast mode operation |
| US8475025B2 (en) | 2006-12-22 | 2013-07-02 | Osram Opto Semiconductors Gmbh | Light-emitting device |
| CN111398201A (en) * | 2020-06-08 | 2020-07-10 | 翼捷安全设备（昆山）有限公司 | Optical gas detector |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5150243A (en) * | 1989-06-12 | 1992-09-22 | Fujitsu Limited | Method and apparatus for monitoring an optical network interface |
-
1993
- 1993-04-14 CN CN93104451A patent/CN1046830C/en not_active Expired - Fee Related
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100546225C (en) * | 2003-07-28 | 2009-09-30 | 爱默生电气公司 | The method and apparatus that is used for the optical receiver of low intensity optical communication with the fast mode operation |
| CN100472207C (en) * | 2004-08-16 | 2009-03-25 | 日本电气株式会社 | Moisture detection label, moisture detection device, moisture detection method, power shutoff method, and electronics device |
| US8475025B2 (en) | 2006-12-22 | 2013-07-02 | Osram Opto Semiconductors Gmbh | Light-emitting device |
| CN111398201A (en) * | 2020-06-08 | 2020-07-10 | 翼捷安全设备（昆山）有限公司 | Optical gas detector |
Also Published As
| Publication number | Publication date |
|---|---|
| CN1046830C (en) | 1999-11-24 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US5262639A (en) | Fiber optic cable monitoring method and apparatus including moisture detection and bending loss detection | |
| CN207866878U (en) | A kind of optical fiber type current measuring device | |
| EP0136271B1 (en) | Apparatus for detecting tapping of light energy from an optical fiber | |
| CA2372864A1 (en) | System for monitoring cables | |
| CN104467984A (en) | Distributed type optical fiber acoustic wave communication method and device | |
| CN101055294A (en) | Dynamotor rotor voltage and current measuring method and its device | |
| US20180371898A1 (en) | Fixed-wavelength fiber optic telemetry | |
| CN1046830C (en) | Fiber optic cable monhoring system | |
| CN108594081A (en) | A kind of submarine cable Fault of Insulating Breakdown locating and detecting device | |
| CN110715752A (en) | Optical cable joint box detection system and method | |
| CN1236234A (en) | Fiber optic cable monitoring system | |
| CN103149154A (en) | Method and device for monitoring dirtiness of insulator | |
| CA2065785C (en) | Fiber optic cable monitoring system | |
| CN1888834A (en) | Optical fiber grating sensor wave length measuring system | |
| CN111121873A (en) | Distributed optical fiber sensing device | |
| CN109959847B (en) | Optical fiber passive pollution flashover monitoring system | |
| CA2237377C (en) | Fiber optic cable monitoring system | |
| Holst | Fiber-optic intensity-modulated sensors for continuous observation of concrete and rock-fill dams | |
| CN113810113A (en) | Base station system for optical fiber sensing communication and implementation method | |
| KR100576152B1 (en) | Optical signal detector | |
| US5903221A (en) | Method and apparatus for determining the moisture level in a buried splice | |
| CN212391610U (en) | Optical cable joint box positioning system based on optical fiber coding | |
| CN107195373B (en) | Photoelectric composite leaky coaxial cable, leaky cable monitoring system and detection method | |
| CN109949992A (en) | A kind of power cable with shelf depreciation self-checking function | |
| CN116698373A (en) | Optical fiber sensing type submarine cable fault positioning online diagnosis system and diagnosis method thereof |
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 | ||
| C19 | Lapse of patent right due to non-payment of the annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |