Method for creating a fiber optic connection, using a splicer

Abstract

Method for establishing a fiber optic connection between a first optical fiber (21) and a second optical fiber (22) associated therewith, in particular for establishing a continuous fiber optic connection between a central office (CO) and an optical telecommunications socket (OTO) in a building (1), wherein the first optical waveguide (21) is or will be connected to a first coding readable via the first optical waveguide (21), in particular in the form of a first fiber Bragg grating (FBG1), wherein the second optical waveguide (22) is or will be connected to a second coding, in particular in the form of a second fiber Bragg grating (FBG2), which can be read out via the second optical waveguide (22), comprising the steps - reading the first coding of the first optical fiber (21), - reading the second coding of the second optical fiber (22), - Checking the assignment of the two read codes, - connecting the first optical fiber (21) to the second optical fiber (22), wherein, for reading out the coding of the first and / or the second optical waveguide (21, 22), a measuring means (25) is connected to the first optical waveguide (21) and / or to the second optical waveguide (22), wherein the measuring means (25) reads out the characteristic of the coding connected to the first optical waveguide (21) and / or the second optical waveguide (22) via a portion (27) of a signal (26) emitted by the measuring means (25) that is reflected at the coding, and wherein the measuring means (25) is connected to the first optical fiber (21) and / or to the second optical fiber (22) by means of an optical fiber stub (28).

Description

[0001] The present invention relates to a method for establishing a fiber optic connection and a connection protocol, the use of a splicing device in such a method, and the use of a splicing device for temporarily connecting an optical fiber to a measuring device.

[0002] With the increasing use of optical fibers for direct cabling of private households, the term Fiber-To-The-Home (FTTH) is commonly used. However, with such FTTH applications, the fiber optic network operator needs to specifically address each individual private connection in order to be able to activate a specific connection or disconnect it from the data network as needed.

[0003] For example, WO 96 / 31022 A1 describes an optical fiber network between a service provider and an end user. The individual end users and the nodes are equipped with a reflector that creates a unique reflection pattern. The service provider can thus check the connection to each individual end user and ensure that this connection is functioning properly. If necessary, interruptions or faults in the network can be easily localized. The disadvantage is that a single interruption in the network affects a large number of end users. If an individual user is to be disconnected from the network, this disconnection must occur at the last node, where a fiber optic cable splits into several individual lines. The service provider must therefore have access to the street cabinet or the house connection box.

[0004] DE 20 2007 009 480 U1 discloses a device for splicing optical fibers comprising a fiber and a sheath surrounding the fiber. The optical fibers are spliced according to the color of their sheath.

[0005] US 2007 / 0277191 A1 discloses a method for storing data in an optical data storage device, the method comprising the steps of: encoding information and determining a multi-channel grating structure for the encoded information and attaching the grating structure to an optical waveguide in such a way that the multi-channel grating, in use, causes a change in a property of the optical radiation passing through the waveguide, the change in the property being characteristic of the encoded information.

[0006] EP 1 691 225 A1 discloses a method for marking electrical or optical conductors comprising the steps of (a) measuring at least one physical property of at least one electrical or optical conductor, (b) generating coded information as a function of the measured value of the at least one physical property according to a predetermined coding algorithm, and (c) marking the at least one electrical or optical conductor, wherein the coded information is readable from the marking.

[0007] It is also known that a service provider can provide a direct connection to an end user. For example, a service provider's central office has a main distribution frame, which is connected to the individual street cabinets via a fiber bundle containing numerous individual fibers and then directly to the end user's telecommunications socket via a house connection box. The advantage of such a direct connection between the service provider and the end user is that a disruption only affects a single end user. Furthermore, the service provider can connect or disconnect the individual end user from the network directly in its main distribution frame. Access to the street cabinet or the house connection box to patch connections is no longer necessary.

[0008] However, establishing and managing such individual connections is complex, as precise records must be kept of which connection leads to which end user. If the connection is mechanically damaged, for example, if a trunk cable or a distribution cable with one or more fiber bundles is severed during excavation work, it is difficult to correctly reestablish the connections between the individual fibers.

[0009] The object of the invention is to be able to create such an individual connection correctly and easily, in particular to connect an address or a code of the end user with the correct connection of the main distribution frame of the service provider and to create a connection protocol as simply as possible.

[0010] This object is achieved by the methods defined in the independent patent claims. Further embodiments are disclosed in the dependent patent claims.

[0011] A method according to the invention for establishing a fiber optic connection between a first optical fiber and a second optical fiber associated therewith, in particular for establishing a continuous fiber optic connection between a central office of a service provider and an optical telecommunications socket of an end user in a building, comprises the steps: - Reading a first coding of the first optical fiber, - Reading a second coding of the second optical fiber, - Checking the assignment of the two read codes, - Connecting the first optical fiber to the second optical fiber.

[0012] The first optical fiber is connected to a first code that can be read out via the first optical fiber or can be connected to such a code. The second optical fiber is also connected to a second code that can be read out via the second optical fiber or can be connected to this. An example of a code is a fiber Bragg grating, which can be arranged directly in an end region of the fibers. It is also conceivable for the fiber Bragg grating to be integrated into a connector of the optical telecommunications socket. A fiber Bragg grating is understood not only to be a single fiber Bragg grating but also a fiber Bragg grating array, i.e. a combination of several fiber Bragg gratings that are, for example, inscribed close together in an optical fiber.As an alternative to a fiber Bragg grating, a thin-film filter or a reflective coating on a fiber end face, or a combination of optical components such as prisms, lenses, etc. can be used for coding. By checking the assignment of the two read codes before connecting the two fiber optic cables, it can be ensured that only two assigned fiber optic cables are connected in each situation. This enables the correct assignment between the service provider's central office and the end user's telecommunications outlet, not only when the fiber optic connection is first created but also during maintenance work after a fiber break. The connection between the two fiber optic cables can be established, for example, using a splice (mechanical or thermal), or using a conventional plug-in connection.

[0013] To read the coding of the first and / or second optical fiber, a measuring device is connected to the first optical fiber and / or the second optical fiber. The measuring device reads the characteristics of the coding connected to the first optical fiber and / or the second optical fiber via a portion of a signal emitted by the measuring device that is reflected by the coding. It goes without saying that the order in which the coding of the two optical fibers is read has no influence on the process. It is also conceivable that the coding of the first and second optical fibers is read simultaneously using a suitable measuring device. Accordingly, a simultaneous connection between the measuring device and the two optical fibers would also be necessary.Because the fiber optic cable's coding can be read via the fiber optic cable, it's possible for the coding to be connected to an end of the fiber optic cable that the service provider or installer cannot access. However, the coding can be read from any point along the fiber optic cable, especially if there is a break in the fiber optic connection.

[0014] The measuring device is connected to the first optical fiber and / or the second optical fiber by means of an optical fiber stub. The use of an optical fiber stub enables the measuring device to be equipped with, for example, a standardized connector interface to which an optical fiber stub, for example in the form of a pigtail, is connected to the measuring device. Should the optical fiber stub become worn or damaged, this optical fiber stub can be easily and inexpensively replaced without the measuring device having to be taken to a repair shop for maintenance. The use of an optical fiber stub is also advantageous because, for example, connecting the optical fiber stub or the measuring device to an optical fiber connected to a code to be read out can cause the optical fiber stub to become worn and / or damaged.Especially when a thermal splice is used to read the code, a portion of the fiber optic stub must be cut off when the connection is broken. Once the length of the fiber optic stub is no longer suitable for further connection to an optical fiber, the fiber optic stub can be replaced.

[0015] An alignment mechanism of a splicer can be used to connect the measuring device to the first optical fiber and / or the second optical fiber. Conventional splicers are typically equipped with an alignment mechanism that precisely aligns two clamped optical fiber ends and holds them ready for the subsequent splicing process. For example, the end of the optical fiber stub to be connected can be clamped into a first receptacle of the alignment mechanism, e.g., in a V-groove, and the end of the first and / or second optical fiber to be connected can be clamped into a second receptacle. Typically, the splicer will align the two optical fibers such that the light-guiding cores of the two optical fibers are aligned along the X, Y, and Z axes.Such alignment alone establishes an optical connection, and the measuring device connected to the fiber optic stub can read the coding characteristics of the corresponding fiber optic cable. Mechanical alignment is sufficient for reading, eliminating the need for thermal splicing of the fiber optic cables. However, it is also conceivable that a thermal splice connection is preferred for certain applications. As with normal splicing processes, the arc is triggered and the two fibers of the fiber optic cable and the fiber stub are welded together. As already mentioned, the fiber optic stub or the fiber optic cable can be severed to subsequently release such a connection.

[0016] If the assignment of the two codes read from the first and second fiber optic cables is recognized as matching, a splicer can be used to connect the two fiber optic cables in the usual way. A thermal splice, i.e., a welded connection, is then created between the two fiber optic cables. The connection between the two fiber optic cables is thus established with as little loss as possible. Preferably, the same splicer is used for this purpose that was already used to connect the fiber optic cable to the measuring device. Alternatively, a plug-in connection can also be created. This is particularly advantageous during the initial installation, as the connections can then be planned and the corresponding connectors can already be pre-assembled.

[0017] At least one of the two optical fibers can be arranged in a fiber bundle. Accordingly, the step of reading the code must be repeated with a different optical fiber from the fiber bundle until the associated optical fibers to be connected are found.

[0018] A further object of the present invention relates to the use of a splicing device in a method as described above.

[0019] Another use of a splicing device according to the invention serves for the particularly temporary connection of an optical fiber to a measuring device. The measuring device has an optical fiber stub for connection to the optical fiber. One end of the optical fiber and one end of the optical fiber stub are aligned to one another using an alignment mechanism of the splicing device. It is sufficient for the fiber ends of the optical fiber stub and the optical fiber to be aligned and / or physically contacted. Only a temporary connection is established. A thermal splice, as is usually created with a splicing device, is not absolutely necessary but can be performed depending on the application.By means of such a connection, measuring instruments for various purposes can be connected to an optical fiber at short notice without having to be laboriously equipped with a connector beforehand.

[0020] The measuring device can be used to read a code connected to an optical fiber. Such a code is, for example, in the form of a fiber Bragg grating. However, other codes are also conceivable.

[0021] A further aspect of the present invention relates to a method for creating a connection protocol of a continuous fiber optic connection line from a first to a second network node, in particular from a central office to a telecommunications outlet in a building. The second network node, or the first and second network nodes, are each connected to a code that can be read via a measuring line, in particular in the form of a first and a second fiber Bragg grating. The method comprises the steps: - Connecting a measuring device to the connecting line, in particular to the first network node, - reading the codes of the second network node or the codes of the first and second network nodes, and - Creating a connection protocol comprising the read coding data of the second and, if applicable, the first network node.

[0022] Here and in the following, a network node is defined as the point in an optical communications network where individual components are connected. For example, a network node can be the main distribution frame in a service provider's central office, a street cabinet, a house connection box, or the end user's telecommunications outlet.

[0023] This method is primarily used when establishing an FTTH connection for the first time, where, for example, a blind connection of the individual network nodes, particularly the telecommunications outlets, to the central office is possible. This is typically the case when multiple telecommunications outlets are to be connected simultaneously, for example, when cabling a neighborhood or an apartment building. The connections do not have to be created according to predefined codes; instead, the affiliation of the individual network nodes, particularly the individual telecommunications outlets, to the central office is read and logged only after they are connected.Because the coding of the individual telecommunications sockets can be read from the Central Office, both the line integrity and the assignment of the individual connections can be carried out and logged. If both ends are equipped with a code, the coding of the interconnected network nodes, in particular the Central Office and the telecommunications socket, can be directly read and logged accordingly. At a later point in time, it is possible to precisely trace which network nodes are connected to each other, and in particular which telecommunications socket is connected to which connection in the Central Office. If the individual connection lines of the Central Office are connected with a code, it is even possible to trace which connection line of the Central Office the telecommunications socket is connected to.It goes without saying that the individual network nodes, especially the individual telecommunications outlets, have individual and unique coding, allowing for unambiguous identification. In addition to the coding data, the connection log can also contain information about the fiber type used, the length, and the transmission characteristics of the connecting line, such as attenuation, reflection, dispersion, etc. Data for local identification is also possible.

[0024] The coding data of the second network node or both network nodes, in particular the central office and the telecommunications outlet, and in particular their affiliation, can be stored in a database. Capturing and storing such data enables the individual fiber optic cables to be correctly reconnected in the event of a connection interruption.

[0025] The coding data in the database can be used to address individual network nodes, particularly individual telecommunications outlets in the communications network. For example, it is conceivable that certain information is only sent to network nodes that meet certain criteria. For example, network access can be linked to the payment of a fee. However, it is also conceivable that certain information is only available by ordering a corresponding subscription.

[0026] The invention is explained in more detail below with reference to figures which merely represent exemplary embodiments: Fig. 1: A schematic representation of an FTTH network, and Fig. 2: a schematic representation of an inventive use of a splicing device.

[0027] Fig. Figure 1 shows a schematic representation of an FTTH network. Starting from a service provider's central office (CO) and a corresponding main distribution frame (OMDF), a trunk cable (12) can be seen, which leads from the main distribution frame (OMDF) to the street cabinet (DP). The trunk cable is typically a multi-fiber cable or fiber bundle. Each of the individual optical fibers in the trunk cable is connected to an individual fiber Bragg grating (FBG2). For the sake of simplicity, however, only a single fiber Bragg grating (FBG2) is shown. These fiber Bragg gratings (FBG2) allow the individual identification of the individual fibers of the trunk cable (12), which can be read, for example, at the street cabinet (DP).

[0028] The street distributor DP is connected to a house connection box BEP of a building 1 via a distribution cable 10, which also comprises several optical fibers. In the house connection box BEP, the individual optical fibers of the distribution cable 10 are then divided into individual in-house cables 2. One in-house cable 2 leads from the house connection box BEP to a telecommunications socket OTO of an end user or an individual apartment. In order to be able to address each end user individually, the corresponding in-house cable 2 is connected to a coding in the form of a fiber Bragg grating FBG1. Here, too, for the sake of simplicity, a fiber Bragg grating is only shown for one end user. It goes without saying that each end user is assigned a corresponding coding in the form of a fiber Bragg grating.These fiber Bragg gratings can be arranged directly in the corresponding in-house cable 2 or in a connector of the in-house cable 2, built into the telecommunications socket OTO, or into a coupling element of the telecommunications socket OTO. A connection box 4 is connected from the end user's telecommunications socket OTO to the optical telecommunications socket OTO via a connection cable 3. The connection box 4 converts, for example, an optical data signal into an electrical signal. This allows the end user to connect a telephone 6, a computer 7, a TV set 8, and other appropriately equipped devices via a conventional internal LAN. Shown in . Fig. 1 is the LAN cabling as Ethernet cabling 5.

[0029] When connecting an end user to the service provider's Central Office CO for the first time, for example, an optical fiber from the distribution cable 10 is identified in the house connection box BEP. This fiber optic cable is connected with the corresponding coding in the form of a fiber Bragg grating FBG2 via the street distribution box DP and the trunk cable 12. The fiber optic cable to be connected, or the corresponding in-house cable 2, is also identified, which leads to the corresponding end user or to their coding in the form of the fiber Bragg grating FBG1. Once the two corresponding fiber optic cables have been identified with their corresponding coding, they can be connected in the house connection box BEP. Such a connection is usually made using a splicer and a thermal splice. However, a plug-in connection is also conceivable.

[0030] However, if the service provider has not yet specified the assignment of the FBG2 code of the Central Office CO to the FBG1 code of the individual telecommunications outlet OTO, the connection can be established without prior assignment. However, after the connection has been established, it must be measured and its codes read out and logged accordingly.

[0031] Fig. Figure 2 shows the schematic use of a splicing device 20 for connecting a first optical fiber 21 to a second optical fiber 22. The first optical fiber 21 is connected to an end user, or more precisely, to an optical telecommunications outlet OTO of the end user. At the same time, the optical fiber 21 is connected to a unique code in the form of a fiber Bragg grating FBG1. The optical fiber 22 is connected either directly or, for example, via one or more street cabinets DP (see Fig. 1) is connected to a main distribution frame (OMDF) of a central office CO of a service provider. The optical fiber 22 is also connected to an individual coding in the form of a fiber Bragg grating (FBG2). In the diagram according to Fig. 2, both optical fibers 21 and 22 are arranged in a fiber bundle 14. It goes without saying that each optical fiber of the two fiber bundles 14 is connected to an individual coding in the form of a fiber Bragg grating. For the sake of simplicity, however, only one fiber Bragg grating is shown.

[0032] To determine the correct optical fibers 21 and 22 to be connected to each other, they are temporarily connected to a measuring device 25 by means of a splicer 20. A fiber optic stub 28 is connected to the measuring device 25, and its free end is clamped into the splicer 20 or into a first receptacle of an alignment mechanism of the splicer 20. For example, the fiber optic 21 is clamped into a second receptacle of the alignment mechanism of the splicer 20. The ends of the fiber optic stub 28 and the fiber optic 21 can now be aligned with each other in the usual way. The splicer has a display 23 for this purpose, which shows the two ends in an enlarged view, enabling precise alignment. It does not matter whether this alignment is carried out automatically or manually.As soon as the two ends are aligned, a signal 26 can be emitted from the measuring device, which is sent along the optical fiber path through the optical fiber stub 28, via the aligned ends of the optical fiber stub 28 and the optical fiber 21, via the optical fiber 21 to the optical telecommunications socket OTO. Since the optical fiber 21 is connected to a fiber Bragg grating FBG1, a portion of the signal 26 is reflected by this fiber Bragg grating FBG1 and, as the reflected portion 27 of the signal 26, finds its way back along the optical fiber path to the measuring device 25. The measuring device 25 will accordingly recognize and display the read-out coding based on the reflected portion 27 of the signal 26. If the displayed coding is the desired coding of the optical fiber to be connected orof the end user to be connected, the optical fiber 21 can be marked accordingly by a technician. However, if the read code does not correspond to the correct value, another optical fiber can be pulled from the fiber bundle, connected to the optical fiber stub 28 in the splicer 20 receptacle, and the code read again. This step is then repeated until the read code corresponds to the code assigned to the end user to be connected.

[0033] In a similar manner, the second optical fiber 22 is now connected to the measuring device 25 via the splicing device 20. The measuring device 25 in turn transmits a signal 26, which travels via the resulting optical fiber link to the service provider's main distribution frame OMDF. The optical fiber 22 is in turn equipped with a fiber Bragg grating FBG2 in the area of the main distribution frame OMDF, so that the signal 26 is again partially reflected and can be evaluated again accordingly in the measuring device 25. The evaluation of the coding of the optical fiber 22 is again repeated with different fibers of the fiber bundle 14 until the corresponding optical fiber to be connected is identified. It goes without saying that the order in which the coding of the optical fibers (21, 22) is read out has no influence on the process.

[0034] Subsequently, the fiber stub 28, which originates from the measuring device 25, is removed from the splicer 20, and the two previously identified optical fibers 21 and 22 are each clamped into the splicer 20. A conventional splicing process, for example, a thermal splicing process, is performed, whereby the alignment of the two optical fibers 21, 22 can be checked on the display 23 of the splicer 20.

Claims

[1] Method for establishing a fiber optic connection between a first optical fiber (21) and a second optical fiber (22) associated therewith, in particular for establishing a continuous fiber optic connection between a central office (CO) and an optical telecommunications outlet (OTO) in a building (1), wherein the first optical waveguide (21) is or will be connected to a first coding readable via the first optical waveguide (21), in particular in the form of a first fiber Bragg grating (FBG1), wherein the second optical waveguide (22) is or will be connected to a second coding, in particular in the form of a second fiber Bragg grating (FBG2), which can be read out via the second optical waveguide (22), comprising the steps - reading the first coding of the first optical fiber (21), - reading the second coding of the second optical fiber (22), - Checking the assignment of the two read codes, - connecting the first optical fiber (21) to the second optical fiber (22), wherein, for reading out the coding of the first and / or the second optical waveguide (21, 22), a measuring means (25) is connected to the first optical waveguide (21) and / or to the second optical waveguide (22), wherein the measuring means (25) reads out the characteristic of the coding connected to the first optical waveguide (21) and / or the second optical waveguide (22) via a portion (27) of a signal (26) emitted by the measuring means (25) that is reflected at the coding, and wherein the measuring means (25) is connected to the first optical fiber (21) and / or to the second optical fiber (22) by means of an optical fiber stub (28). [2] Method according to claim 1, wherein an alignment mechanism of a splicing device (20) is used for connecting the measuring means (25) to the first optical fiber (21) and / or to the second optical fiber (22). [3] Method according to one of claims 1 or 2, wherein a splicing device (20) is used to connect the first optical waveguide (21) to the second optical waveguide (22). [4] Method according to one of claims 1 to 3, wherein at least one of the two optical waveguides (21, 22) is arranged in a fiber bundle (14) and the step of reading out the codes is repeated with a different optical waveguide from the fiber bundle (14) until the optical waveguides (21, 22) assigned to one another and to be connected are found. [5] Use of a splicing device (20) in a method according to one of claims 1 to 4. [6] Use of a splicing device (20) according to claim 5 for the in particular temporary connection of an optical waveguide (21, 22) to a measuring means (25), wherein the measuring means (25) has an optical waveguide stub (28) for connecting the optical waveguide (21, 22), wherein one end of the optical waveguide (21, 22) and one end of the optical waveguide stub (28) are aligned with one another by means of an alignment mechanism of the splicing device (20). [7] Use of a splicing device (20) according to claim 6, wherein the measuring means (25) serves to read out a coding connected to an optical waveguide (21, 22), in particular in the form of a fiber Bragg grating (FBG1, FBG2).

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