JPH0865242A - Repeating part bypass device for optical transmission repeater system - Google Patents

Abstract

PURPOSE: To save labor and to improve security and improve the operation probability by omitting the conveyance of a measuring instrument for fault search by returning back scattered light, which is generated at the broken point of an optical transmission line, to a light transmitting terminal by optically bypassing the repeating part of an optical transmission repeater system when any fault is generated. CONSTITUTION: At the optical transmission repeater system interposed at optical transmission lines 6 and 9 provided between optical transmission terminal station equipment 2 and 4, the optical signal switched through the optical transmission line 6, where no fault occurs, is multiplexed with a main optical signal and transmitted. The switched optical signal is extracted by a switching electric signal extracting device 14 of repeating parts 10 and 12 as a switched electric signal and supplied to switching devices 18 and 20 of the optical transmission line 8 where any fault occurs, and the repeating part 12 is switched to an optical repetition bypass part 16. Therefore, the optical transmission repeater system up to the position, where the fault occurs, is respectively bypassed by the optical repetition bypass part 16 and optical transmission is not repeated but the position of the fault generated at the optical transmission line 8 can be specified.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a repeater bypass device for an optical transmission repeater, which bypasses the repeater of the optical transmission repeater when searching for a fault in the optical transmission line.

In recent years, with the development of optical communication technology, high-speed and large-capacity transmission by wire has become possible, and many long-distance optical transmission lines have been provided on land and under the sea. In this long-distance optical transmission line as well, similar to the conventional electrical long-distance transmission line, since there is signal attenuation and the like, an optical transmission repeater is provided for each predetermined distance.

A fault may occur also in this optical transmission line, and it is necessary to search for the fault and eliminate the fault.

[0004]

2. Description of the Related Art The above-mentioned optical transmission line (optical fiber cable) fault detection is performed by optically connecting a fault detection measuring device to an optical fiber cable in an optical transmission terminal device provided on the optical transmission line. Combine and send light for obstacle search. At the break point generated in the optical fiber cable, the propagating light becomes backscattered light and returns to the sending end. The position of the break point (fault occurrence point) is determined from the delay time, loss, etc. of the returning light.

The optical fiber cable to which this conventional fault search method is applied is provided with an optical transmission repeater at every predetermined distance as described above, and the optical transmission repeater temporarily converts an optical signal into an electrical signal. After the conversion, the signal is reproduced, converted into an optical signal again, and transmitted through the optical fiber cable.

[0006]

Therefore, although the above-described method for searching for a failure is effective for an optical fiber cable up to an optical transmission repeater, the method for searching for a failure is used because the optical transmission repeater has the above-mentioned configuration. The light is interrupted by the optical transmission repeater and is not transmitted beyond the optical transmission repeater. Therefore, it is only possible to search for a failure up to the optical transmission repeater, that is, the optical fiber cable for each repeater section. For this reason, it has been necessary to carry a fault-finding measuring instrument to the location of the optical transmission repeater installed at both ends of the faulty section for fault-finding of the optical fiber cable.

For this reason, not only a great deal of labor is required to search for a failure, but also the time spent therefor is increased, and the time required to restore the transmission line is inevitably long.

The present invention has been made in view of the above technical problems, and it is possible to identify a fault location occurring in an optical transmission line without carrying a fault hunting apparatus, thereby bypassing a relay section of an optical transmission repeater. The purpose is to provide a device.

[0009]

FIG. 1 shows a principle block diagram according to claim 1. FIG. 2 shows a block diagram of the principle of the invention according to claim 2. FIG. 3 shows a principle block diagram of the invention according to claim 3.

According to the first aspect of the present invention, as shown in FIG. 1, in an optical transmission repeater provided on two optical transmission lines 6 and 8 provided between the optical transmission terminal devices 2 and 4, Relay sections 10 and 12 provided in the optical transmission repeater, and a switching electric signal extracting apparatus 14 provided in the relay section 10 of the optical transmission line 6 in which no failure has occurred and extracting a switching electric signal;
An optical relay bypass section 16 for bypassing the repeater section 12 provided in the failed optical transmission line 8 and a failure occurred in response to the switching electric signal output from the switching electric signal extracting device 14. Switching device 1 for switching the relay section 12 interposed in the optical transmission line 8 to the optical relay bypass section 16
8 and 20 are provided.

According to a second aspect of the present invention, as shown in FIG. 2, in the repeater bypass device of the optical transmission repeater according to the first aspect, the repeaters 10 and 12 are provided with a demultiplexer 22 and a main optical signal. It is configured by a relay unit 24, a switching optical signal relay unit 26, and a multiplexer 28, and the switching electrical signal extraction device 14 is provided in the switching optical signal relay unit 26.

According to a third aspect of the present invention, as shown in FIG. 3, in the repeater bypass device of the optical transmission repeater according to the first aspect, the switching electrical signal extracting device 14 includes the repeater unit 1.
It is characterized in that it is provided on the output side of the 0, 12 electric signal regeneration repeating section 30.

[0013]

According to the first aspect of the present invention, the switching optical signal is multiplexed with the main optical signal and transmitted via the optical transmission line in which no failure has occurred. The multiplexed switching optical signal is
It is extracted as a switching electric signal by the switching electric signal extracting device 14 of the relay units 10 and 12.

The extracted switching electric signal is supplied to the switching devices 18 and 20 on the side of the optical transmission line where the fault has occurred. The switching devices 18 and 20 switch the relay section 12 provided on the failed optical transmission line 8 to the optical relay bypass section 16.

Therefore, the optical transmission repeater installed up to the faulty optical transmission line and up to the faulty point are bypassed by the optical relay bypass section 16, respectively. The optical transmission will not be interrupted by the optical transmission repeater, and the optical signal for fault investigation will be transmitted to the fault location, and the backscattered light generated at the fault location will be optically transmitted to the optical transmission terminal equipment. It is returned to the combined measuring instrument for the faulty terminal station and used to search for the location of the fault.

According to the second aspect of the invention, the switching optical signal is wavelength-multiplexed with the main optical signal and transmitted, and the same fault investigation as that of the first aspect of the invention is performed. It is possible to eliminate the need to influence the main optical signal by the switching signal, eg to provide control bits in the main optical signal.

The invention according to claim 3 is different from the invention according to claim 2 in that the above-mentioned influence occurs, but it is not necessary to provide a switching signal relay section.

[0018]

FIG. 4 shows an embodiment of the invention described in claims 1 to 3. In FIG. 4, reference numerals 30 ₁ and 30 ₂ denote optical transmission lines (hereinafter, an optical fiber cable will be described).
An optical transmission terminal device that transmits and receives an optical signal via 32,
Reference numerals 34 ₁ and 34 ₂ are optical transmission repeaters provided in the optical fiber cable 32. Optical transmission terminal equipment 30 ₁ , 30
_The control units 36U and 36D are provided in the _second unit. The optical fiber cable 32 in which the optical transmission repeaters 34 ₁ and 34 ₂ are provided is an upstream optical fiber cable (uplink line) 32.
It is composed of U and a downstream optical fiber cable 32D. The letter U attached to the reference number represents the uphill and the letter D represents the downhill. same as below.

Then, the optical transmission repeater 34₁, 34₂of
The upstream optical fiber cable 32U corresponding part is the switching part 38
₁U, relay section 40₁U, optical fiber cable for bypass
42 ₁U and switching unit 44₁Composed of U.
Optical transmission repeater 34₁And optical transmission repeater 34₂Uphill
The optical fiber cable 32D corresponding part is also configured in the same manner.
It

The switching unit 38 ₁ U switches the optical signal from the upstream optical fiber cable 32 U to either one of the bypass optical fiber cable 42 ₁ U and a demultiplexer 46 ₁ U to be described later and outputs the optical signal. Is. Switching unit 4
4 ₁ U is for switching to either one of the bypass optical fiber cable 42 ₁ U and a multiplexer 52 ₁ U which will be described later to emit light to the upstream optical fiber cable 32 U.

The repeater 40 ₁ U includes a demultiplexer 46 ₁ U, a main optical signal repeater 48 ₁ U, and a switching optical signal repeater 50.
₁ U and a multiplexer 52 ₁ U. The demultiplexer 46 ₁ U demultiplexes the switching optical signal emitted from the control unit 36 of the optical transmission terminal device 30 ₁ and the main optical signal wavelength-multiplexed with the switching optical signal. Multiplexer 52 ₁
U wavelength-multiplexes a main optical signal from an electric-optical conversion unit 58 ₁ U described below and a switching optical signal from an electric-optical conversion unit 64 ₁ U described below.

The main optical signal repeating section 48 ₁ U comprises an optical-electrical converting section 54 ₁ U, a regenerative repeating section 56 ₁ U, and an electrical-optical converting section 58 ₁ U. In addition, the switching optical signal relay unit 50 ₁
U includes an opto-electric conversion unit 60 ₁ U, a control unit 62 ₁ U, and an electro-optical conversion unit 64 ₁ U. The control unit 62 ₁ U is
Outputs a switching electric signal. The switching electric signal is supplied to the switching unit 38 ₁ D and the switching unit 44 ₁ D to switch from the main optical signal relay unit 48 ₁ D side to the bypass optical fiber cable 42 ₁ D side, and the main optical signal Relay section 4
8 ₁ D is bypassed by the bypass optical fiber cable 42 ₁ D.

In FIG. 4, the optical transmission terminal station device 30 is shown.₁Three
0₂Corresponds to the optical transmission terminal equipments 2 and 4 of FIGS.
Upstream optical fiber cable 32U, downstream optical fiber cable
The cable 32D corresponds to the optical transmission lines 6 and 8 of FIGS. 1 to 3.
To do. Relay section 40₁U, relay section 40₁D is the relay of FIG.
Corresponds to parts 10 and 12. Optical fiber cable for bypass
Le 42₁U, optical fiber cable for bypass 42₁D
Corresponds to the optical relay bypass section 16 of FIGS.
Replacement part 38₁U, switching unit 38₁D, switching unit 44
₁U, switching unit 44₁D is the switching device of FIGS.
Corresponds to 18, 20. Duplexer 46₁U, duplexer 46₁
D corresponds to the demultiplexer 22 of FIG. 2, and is a repeater 4 for the main optical signal.
8₁U corresponds to the main optical signal repeater 24 in FIG. switching
Optical signal relay unit 50₁U is the switching optical signal relay of FIG.
A multiplexer 52 corresponding to the section 26.₁U is the combiner 28 of FIG.
Corresponding to. Control unit 62₁U is the switching of FIG. 1 and FIG.
It corresponds to the electric signal extraction device 14. The control unit 57 is shown in FIG.
It corresponds to the switching electric signal extraction device 14 of
6₁U, 56₁D is connected to the electric signal regeneration relay unit 30 of FIG.
Correspond.

The operation of the embodiment configured as described above will be described below. In a state where no failure occurs in the upstream optical fiber cable 32U and the downstream optical fiber cable 32D, the control unit 36U of the optical transmission terminal station device 30 ₁ also
Further, the switching optical signal is not generated from the control unit 36D of the optical transmission terminal device 30 ₂ . Therefore, the switching optical signal repeater 5
0 ₁ From the control unit 62 ₁ U of U, electric switching signal from the control unit 62 ₁ D of also switching optical signal relay unit 50 ₁ D is not generated. As a result, the optical signal from the optical transmission terminal equipment 30 ₁ to the optical transmission terminal equipment 30 ₂ is relayed for the main optical signal of the upstream optical fiber cable 32U, each optical transmission repeater 34 ₁ , and optical transmission repeater 34 _2. It is transmitted via the units 48 ₁ U and 48 ₂ U.

Where is the downstream optical fiber cable 32D now?
It is assumed that the crab has a failure (break point). At this time,
Each optical transmission repeater 34₁, 34₂Switching unit 38₁U,
38 ₂U is a relay unit 48 for the main optical signal₁Switch to U side
And the switching unit 38 ₁D, 38₂D is Mitsunobu
No. relay section 48₁It has been switched to the D side.

The measuring device for fault investigation is the optical transmission terminal device 30.
₁Or, the optical transmission terminal device 30₂Down Fiber Optic Cave
Optical transmission terminal equipment, which is optically coupled to
30 ₁Control unit 36U, optical transmission terminal device 30₂Control unit
A switching optical signal is generated from 36D, and the switching optical signal is generated.
Is an upstream optical fiber cable that is wavelength-multiplexed with the main optical signal.
Transmission via 32U or downstream optical fiber cable 32D
To be done.

Therefore, the optical signal transmitted through the upstream optical fiber cable 32U is transmitted to the optical transmission repeater 34 ₁ ,
The signal is propagated through the relay unit 40 ₁ U of 34 _{2 and} the switching units 38 ₁ U and 38 ₂ U switched to the relay unit 40 ₂ U side. The switching optical signal wavelength-multiplexed in the optical signal is demultiplexed by the demultiplexer 46 ₁ U and the demultiplexer 46 ₂ D, and the switching optical signal relay unit 50 ₁ U and the switching optical signal relay unit 50
Propagated to ₂ U. At that time, the main optical signal demultiplexed by the demultiplexer 46 ₁ U propagates to the main optical signal repeater 48 ₁ U and the main optical signal repeater 48 ₂ U.

The switching optical signal propagated to the switching optical signal relay unit 50 ₁ U and the switching optical signal relay unit 50 ₂ U is electrically converted by the optical-electrical conversion unit 60 ₁ U and the optical-electrical conversion unit 60 ₂ U. is converted to a signal by the control unit 62 ₁ U, is supplied to the control unit 62 ₂ U, the control unit 62 ₁ U, electric signal switched by the control unit 62 ₂ U are extracted. The switching electric signal is used for the switching section 38 ₁ D, the switching section 44 ₁ D, and the switching section 38 ₂ on the down side.
And the switching unit 44 ₂ D.

As a result, the downstream switching unit 38₁D and
And switching unit 44₁D, switching unit 38 ₂D and switching unit 4
4₂D is a switching optical signal relay unit 50.₁D, optical switching
No. relay section 50₂Since it is switched to D side, each optical transmission
Relay device 34₁, 34₂Main optical signal repeater 48₁U,
Main optical signal repeater 48₂U is a switching optical signal relay unit 5
0₁U, switching optical signal relay unit 50₂Viper by U
Will be

Therefore, the fault-finding light transmitted from the fault-finding measuring instrument is transmitted as an electrical signal by the main optical signal repeaters 48 ₁ D and 48 ₂ D on the downstream side of the optical transmission repeaters 34 ₁ and 34 _2. Is converted into an optical signal and transmitted to the downstream optical fiber cable 32D without being transmitted to the downstream optical fiber cable 32D. Since the optical signal is returned to the transmission end side as backscattered light at the break point (fault point), the optical transmission repeater 34 ₁ ,
Even if 34 ₂ intervenes, it is possible to carry out the failure search successfully without the inconvenience and without carrying the failure search measuring device to the optical transmission repeaters installed at both ends of the failure section as in the prior art. Therefore, labor and time are saved, and the time required to restore the transmission path can be shortened.

In the above embodiment, an example in which the switching signal is multiplexed with the main signal by the wavelength multiplexing method has been described.
A control bit consisting of one to a plurality of bits is used as a switching optical signal, and this is multiplexed with an information bit to be transmitted as a main optical signal in a frame and transmitted, and the output side of a regenerative repeater unit of each optical transmission repeater. The control unit 57 (not shown) provided in the above may extract it as a switching bit and use it for switching control of the switching unit.

[0032]

As described above, according to the present invention, by optically bypassing the repeater section of the optical transmission repeater when a failure occurs, it is possible to search for the breakage point in the optical transmission line at the break point. Since the generated backscattered light can be successfully returned to the fault detection light sending end, it is possible to eliminate the necessity of transporting the fault detection measuring device to the optical transmission repeaters installed at both ends of the fault section. As a result, labor and time are saved, labor for trouble detection and labor efficiency are improved, and the time required for transmission line restoration is greatly reduced.

[Brief description of drawings]

FIG. 1 is a block diagram of the principle of the invention according to claim 1.

FIG. 2 is a principle block diagram of the invention according to claim 2;

FIG. 3 is a principle block diagram of the invention according to claim 3;

FIG. 4 is a diagram showing an embodiment of the invention described in claims 1 to 3;

[Explanation of symbols]

2 optical transmission terminal equipment 4 optical transmission terminal equipment 6 optical transmission path 8 optical transmission path 10 relay section 12 relay section 14 switching electrical signal extraction apparatus 16 optical relay bypass section 18 switching apparatus 20 switching apparatus 22 main optical signal relay section 24 Switching optical signal repeater unit 30 Electric regeneration repeater unit 30 ₁ Optical transmission end station device 30 ₂ Optical transmission end station device 32U Upstream optical fiber cable 32D Downstream optical fiber cable 40 ₁ U Repeater unit 40 ₁ D Repeater unit 48 ₁ U Main optical signal Repeater unit 48 ₁ D switching optical signal repeater unit 56 ₁ U regenerative repeater unit

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI technical display location H04B 10/16

Claims (3)

[Claims] 1. An optical transmission repeater interposed between two optical transmission lines provided between optical transmission terminal devices, wherein a repeater unit provided in the optical transmission repeater and an optical device having no failure are provided. A switching electrical signal extraction device that is provided in the relay section of the transmission line and extracts the switching electrical signal, an optical relay bypass section that bypasses the relay section that is interposed in the optical transmission path in which a failure has occurred, and the switching electrical signal. An optical transmission repeater, comprising: a switching device for switching a relay unit interposed in an optical transmission line in which a failure has occurred in response to a switching electric signal output from a signal extraction device to an optical relay bypass unit. Relay unit bypass device. 2. The repeater bypass device for an optical transmission repeater according to claim 1, wherein the repeater comprises a demultiplexer, a main optical signal repeater, a switching optical signal repeater, and a multiplexer. A switching electric signal extracting device is provided in the switching optical signal repeating unit, and a repeater bypass device for an optical transmission repeater. 3. The repeater bypass device for an optical repeater according to claim 1, wherein the switching electric signal extracting device is provided on the output side of the electric signal regeneration repeater of the repeater. A relay unit bypass device.