JP2005201946A - Method of branching and distributing optical fiber, optical fiber sheet used for method of branching and distributing optical fiber and housing tray - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To establish an optical network at a low cost by efficiently installing and constructing the branch-connect of optical fibers in an optical closure or an optical termination box. <P>SOLUTION: In the method of dividing and distributing optical fibers, a weaving body 77, in which a single or a plurality of IP type optical devices 71A divided from an IP type optical fiber 55A to a plurality of optical fibers 55A, a single or a plurality of RF type optical devices 71B divided from an RF type optical fiber 55B to a plurality of optical fibers 55B, and a weaving part 75 in which the plurality of optical fibers 55A and 55B branched at the respective optical devices 71A and 71B are crossed, are formed in a module, is provided in a housing tray 73. The optical fibers 55A and 55B which are separated into the IP type and the RF type are connected to the introducing side of the respective IP type and RF type optical devices 71A and 71B of the weaving body 77, and one line of the IP type and one line of the RF type for each subscriber are distributed to the distribution side of the weaving body 77 via the weaving part 75. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an optical fiber branching and distributing method, an optical fiber sheet used in the optical fiber branching and distributing method, and a storage tray, and more particularly to passive optical components called optical couplers and optical splitters that demultiplex and multiplex optical signals. A light that constructs and constructs a PON (Passive Optical Network) at low cost by efficiently laying and constructing optical fiber branch connections in optical closures and optical termination boxes using a certain optical device and braided part. The present invention relates to a fiber branching and distributing method, an optical fiber sheet used in an optical fiber branching and distributing method, and a storage tray.

  In recent years, the rapid spread of broadband, the expansion of optical networks such as FTTH (Fiber-to-the-Home), and the provision of new information communication services that combine broadcasting and communication have been carried out. For example, there is “3-wavelength transmission” using an optical fiber core as standardized by ITU-T G.983.3, but transmission equipment is expensive and devices such as wavelength filters and splitters are required. Therefore, it is not practically provided commercially.

  At present, a generally used method is an optical network wiring method in which two optical fibers are used, one core is bidirectional communication, and the other core is video distribution (one direction).

  What is used for two-way communication is generally called an “IP (Internet Protocol) system” because it is connected to the Internet via a provider that provides an ISP service. On the other hand, the video wiring is substantially synonymous with the broadcasting system, and is often called “RF (Radio Frequency) system”.

  Also, a relay connecting between stations such as telephone stations equipped with a main distribution board (MDF: Main Distribution Frame, abbreviated as “MDF”) or an intermediate distribution board (IDF: Intermediate Distribution Frame, hereinafter abbreviated as “IDF”). In systems and trunk systems, IP systems and RF systems are often transmitted by being separated by separate cables. However, in the access system, both are transmitted by one cable. Therefore, the number of target cores is taken out by an optical closure or an optical termination box near the end user and pulled down by a two-core drop cable. In the case of an apartment house, the same thing may be done in the optical termination box after the withdrawal.

  For example, in an optical closure, a plurality of extra-length storage trays are stacked and placed inside the closure housing, the number of target cores is taken out from the optical fiber cable introduced to one end of the closure housing, and the closure housing The number of target cores is taken out from the optical fiber drop cable introduced to the other end of the optical fiber, and the optical fiber strands of the target number of cores on one end side and the other end side of the closure housing are combined in each extra length storage tray. (See, for example, Patent Document 1 and Patent Document 2).

  The optical termination box has basically the same structure as the above optical closure, and an extra length storage case and a separation core storage case are provided in the extra length processing case. The optical fiber tape cores of the number of target cores taken out from the optical fiber cable are separated into single cores after a necessary extra length is secured in the separation core storage case, and an SC type, for example, is attached to the end of each single optical core. An optical connector is attached, and each SC type optical connector is inserted into the case inside of the connector adapter. In some cases, the above-described separation core storage cases are stored in a plurality of stages in the optical termination box (see, for example, Patent Document 3, Patent Document 4, and Patent Document 5).

  Referring to FIGS. 8 and 9, the branch connection state of the optical fiber will be described in more detail. Generally, for example, an aerial optical fiber cable 201 as an optical fiber cable for an access system is shown in FIG. As shown, a large number of optical fiber ribbons 205A made up of four IP optical fiber strands 203 and an optical fiber ribbon 205B made up of four RF optical fiber wires 203 are used.

  The aerial optical fiber cable 201 includes a first strength member 209 provided at the center of a slot rod 207 and a plurality of optical fiber tape cores 205A and 205B assembled in a plurality of slots 211 arranged around the first strength member 209. For example, a metal tape 213 as a tape winding is vertically wound around the outer periphery of 207, and a long optical fiber portion 217 configured by being sheathed with an outer sheath 215 such as a sheath resin around the outer periphery of the metal tape 213. Is provided. Furthermore, a long cable support line portion 223 is provided in which the periphery of the second strength member 219 as a suspension line is covered with a sheath resin 221. The cable support line portion 223 and the optical fiber portion 217 have a neck portion 225 attached thereto. Are integrated in parallel with each other.

  In addition, as shown in FIG. 11A, the optical fiber drop cable 227 branched from the above-described aerial optical fiber cable 201 has an optical element portion 229 having, for example, two optical fiber strands 203 (or An optical fiber core or an optical fiber tape) and a pair of strength members 231 are attached to both sides parallel to the vicinity thereof, and these are collectively thermoplastic such as PVC or flame retardant PE. A notch portion 235 is formed on the surface of the cable sheath 233 on both sides of the optical fiber 203 in a direction orthogonal to the direction in which the strength members 231 are connected. .

  Further, the cable sheath 233 of the optical element portion 229 is provided with a long cable support wire portion 241 in which a support wire 237 made of, for example, a steel wire is covered with a sheath material 239 made of the same resin as the cable sheath 233 in parallel with each other at the neck portion 243. It is integrated through. In this case, the cable sheath 233 is separated from the cable support line portion 241 at the neck portion 243, and the optical element portion 229 is used as an indoor drop cable as shown in FIG.

  As a conventional optical fiber branch connection method, the IP optical fiber 203A and the RF optical fiber 203B are separated one by one from the optical fiber tape cores 205A and 205B of the above-described overhead optical fiber cable 201. The For example, as shown in FIGS. 8 and 9, in the storage tray 247 of the aerial connection closure 245, one core of the IP optical fiber strand 203A is formed by an IP optical device 249A composed of an optical coupler, an optical splitter or the like. While branching to a plurality of IP optical fiber strands 203A, one core of the RF optical fiber strand 203B is branched to a plurality of RF optical fiber strands 203B by an RF optical device 249B.

  Furthermore, a total of two cores, one each for the IP system and the RF system, out of the plurality of optical fiber strands 203 branched by the IP system optical device 249A and the RF system optical device 249B are two cores of the optical fiber drop cable 227. Connected.

  In the optical fiber branch connection method of FIG. 8, before carrying out the aerial connection work, a braided portion 251 is prepared in the storage tray 247 in advance on the ground, and the IP optical device 249A and the RF optical device 249B are connected. A plurality of branching-side IP optical fiber strands 203A and RF optical fiber strands 203B are connected to the introduction side of the braided portion 251 by fusion splicing portions 253A and 253B.

  In the aerial connection work, the IP system of the aerial optical fiber cable 201 and the RF optical fiber strands 203A and 203B are connected to the introduction side of the IP optical device 249A and the RF optical device 249B by fusion splicing portions 255A and 255B. The two cores of the IP system and the RF system on the distribution side of the braided portion 251 are connected to the two cores of the optical fiber drop cable 227 by fusion splicing portions 257A and 257B.

  In the optical fiber branch connection method of FIG. 9, unlike the above-described FIG. 8, the fusion splicing operation is performed while preparing the braided portion during the aerial connection operation without prior preparation. That is, the IP system of the aerial optical fiber cable 201 and the RF optical fiber strands 203A and 203B are connected to the introduction side of the corresponding IP optical device 249A and the RF optical device 249B by the fusion splicing portions 255A and 255B. A plurality of IP system and RF optical fiber strands 203A and 203B on the branch side of the IP optical device 249A and the RF optical device 249B are combined with a total of two cores of each of the IP system and the RF system to form a braided portion. While producing, the two cores of the IP system and the RF system are connected to the two cores of the optical fiber drop cable 227 by the fusion splicing portions 257A and 257B.

  8 and 9 are examples in which one storage tray 247 is divided into 8 subscriptions, but there are also examples in which the number is divided into other subscriptions, and they are separated into 8 subscriptions and 16 subscriptions. Is common.

  Various connection methods such as fusion splicing and mechanical splicing are employed. Since the optical cable uses the four-fiber optical fiber ribbon 205, the number of subscribers (or the number of withdrawals with a drop cable) is preferably four units, but there is no particular limitation.

Some optical termination devices installed in a station building use an optical fiber sheet group as a unit (see, for example, Patent Document 6). The optical fiber sheet is a sheet in which a plurality of optical fiber strands are bonded between two flexible plastic films via an adhesive layer (see, for example, Patent Document 7 and Patent Document 8). ).
Japanese Patent Publication No. 6-72968 JP-A-6-59136 Japanese Patent Laid-Open No. 10-20129 JP-A-10-268144 JP 2003-107251 A JP 2000-131535 A JP 2001-350032 A JP 2000-329950 A

  By the way, the connection form as shown in FIGS. 8 and 9 is called “knitting”. 8 and 9, the optical fiber strands 203A and 203B are congested and the optical fiber strands 203A and 203B are entangled or unnecessary external force is applied. It may take. As a result, there is a problem that the workability is deteriorated and the laying cost is increased due to the longer work time.

  The above connection form is performed in an optical MDF, optical IDF, optical closure, optical termination box or the like, and when connecting the optical fiber strands 203A and 203B, the optical fiber core wire or the optical fiber tape core wire 205, When the number of optical fibers is large, they are complicated and entangled with each other, resulting in an increase in transmission loss.

  Further, every time an end user applies or cancels, the optical fiber strand 203 is taken out and connected, or the connection of the optical fiber strand 203 is released. It is a very careful work to take out the optical fiber 203 from the above, and there is also a restriction that the live line should not be affected.

  Furthermore, since the work in the above-described aerial connection closure 245 is carried out aerial using a bucket car or the like, it is affected by the weather and wind, resulting in an extremely poor workability compared to work on the ground. Yes. Therefore, as described above, there is a problem that the work becomes more difficult in the complicated work in a state where the optical fiber wires 203A and 203B are congested.

  In addition, the conventional optical fiber sheet defines its structure, dimensions, material, hardness, mechanical properties (flexibility, buckling resistance, reinforcement), manufacturing method, manufacturing conditions, etc. There is nothing related to a method of forming an optical network using a sheet.

  For example, the above-mentioned Patent Document 5 merely defines an oval structure of a termination device for the purpose of high-density mounting of an optical fiber sheet.

  Further, in Patent Document 8 described above, a carbon-coated optical fiber is used as an optical fiber that constitutes the optical fiber sheet, but it is not commercially available for general use, and a normal optical fiber element is used. There was a problem that it was more expensive than the wire.

  The present invention has been made to solve the above-described problems.

  The optical fiber branching and distributing method according to the present invention includes: one or a plurality of IP optical devices that branch from an IP optical fiber to a plurality of optical fibers in advance when connecting a plurality of optical fibers in a storage tray; One or a plurality of RF optical devices branching from a system optical fiber to a plurality of optical fibers, and a braided portion that crosses a plurality of optical fibers branched by each of the IP and RF optical devices, A modular knitted body is provided in a storage tray, and an optical fiber separated into an IP system and an RF system is connected to an introduction side of each IP device of the knitted body and the RF system, and the IP system and the RF system are connected. A plurality of optical fibers branched by each of the optical devices are distributed to each distribution side of the braided body by the braided portion, and each line of IP system and RF system is distributed per subscriber.

  In the optical fiber branching and distributing method according to the present invention, in the optical fiber branching and distributing method, the braided body is preferably an optical fiber sheet including the IP and RF optical devices and the braided portion.

  In the optical fiber branch / distribution method according to the present invention, in the optical fiber branch / distribution method, the storage tray is preferably provided in any of an optical MDF, an optical IDF, an optical closure, and an optical termination box.

  The optical fiber branch / distribution method of the present invention is the optical fiber branch / distribution method in which only the changed line is reconnected from the plurality of lines with little external force applied to a live line other than the changed line during reconnection. It is preferable.

  The optical fiber branching and distributing method of the present invention is the optical fiber branching and distributing method, wherein the optical fiber is an ITU-T G. A highly flexible optical fiber compliant with the international standard of 652 is preferable.

  In the optical fiber branching and distributing method of the present invention, when a plurality of optical fibers are connected in the storage tray, when the host system is looped into the main transmission system and the sub transmission system, the optical fiber of the main transmission system is One or a plurality of main transmission optical devices branching to a plurality of optical fibers, one or a plurality of sub transmission optical devices branching from the sub transmission optical fibers to a plurality of optical fibers, and the main transmission system And a knitted portion obtained by modularizing a plurality of optical fibers branched by each optical device of the sub-transmission system, and a knitted body that is modularized in the storage tray and separated into the main transmission system and the sub-transmission system Is connected to the introduction side of each optical device of the main transmission system and the sub-transmission system of the braided body, and a plurality of optical fibers branched by the respective optical devices of the main transmission system and the sub-transmission system are braided at the braided portion Distribution side One subscriber main transmission system per, is characterized in dispensing a respective one line of the sub-transmission system.

  In the optical fiber branching and distributing method of the present invention, in the optical fiber branching and distributing method, the braided body is an optical fiber sheet including the optical devices of the main transmission system and the sub-transmission system and the braided portion. preferable.

  In the optical fiber branch / distribution method according to the present invention, in the optical fiber branch / distribution method, the storage tray is preferably provided in any of an optical MDF, an optical IDF, an optical closure, and an optical termination box.

  The optical fiber branch / distribution method of the present invention is the optical fiber branch / distribution method in which only the changed line is reconnected from the plurality of lines with little external force applied to a live line other than the changed line during reconnection. It is preferable.

  The optical fiber branching and distributing method of the present invention is the optical fiber branching and distributing method, wherein the optical fiber is an ITU-T G. A highly flexible optical fiber compliant with the international standard of 652 is preferable.

  An optical fiber sheet according to the present invention includes a plurality of introduction-side connection portions that connect one or more IP-based optical fibers and one or more RF-based optical fibers on the optical fiber introduction side, and one on the optical fiber distribution side. A plurality of distribution side connection parts for distributing each one line of the IP system and the RF system per subscriber, and one or a plurality of IP branches from the IP system optical fiber conducting to the introduction side connection part to a plurality of optical fibers Branches at one or more RF optical devices branching from an RF optical fiber conducting to the introduction side connection portion to a plurality of optical fibers, and each of the IP optical device and the RF optical device. A plurality of optical fibers crossed to distribute one line for each of the IP system and RF system per subscriber and to be connected to each distribution side connection section; and each light of the IP system and RF system The device and the braided part Two and a resin film adhered via a sandwich by adhesive layers in order to Joule reduction and is characterized by comprising consist of.

  The optical fiber sheet of the present invention is the optical fiber sheet, wherein the optical fiber is an ITU-T G. A highly flexible optical fiber compliant with the international standard of 652 is preferable.

The storage tray of the present invention is a storage tray provided in any of optical MDF, optical IDF, optical closure, optical termination box,
A plurality of introduction side connection portions for connecting one or a plurality of optical fibers of the IP system and one or a plurality of optical fibers of the RF system on the optical fiber introduction side, and the IP system and the RF per subscriber on the optical fiber distribution side A plurality of distribution-side connection parts for distributing each one line of the system, and one or a plurality of IP-type optical devices branching from the IP-type optical fiber conducting to the introduction-side connection part to the plurality of optical fibers; , One or a plurality of RF optical devices branching from an RF optical fiber conducting to the introduction side connecting portion to a plurality of optical fibers, and a plurality of lights branched by the IP optical devices and the RF optical devices. A braided portion that crosses fibers and distributes one line of each of the IP and RF systems per subscriber and conducts to each of the distribution side connecting portions; and each of the IP and RF optical devices and the braided portion And modularized The provision of the narrowing seen the body and is characterized in.

  In the storage tray of the present invention, in the storage tray, the braided body is sandwiched between two resin films so as to modularize the IP-based and RF-based optical devices and the braided portion through an adhesive layer. A fixed optical fiber sheet is preferred.

  In the storage tray of the present invention, the optical fiber is an ITU-T G. A highly flexible optical fiber compliant with the international standard of 652 is preferable.

  As will be understood from the means for solving the above problems, according to the present invention, an optical device for demultiplexing / multiplexing optical signals and an interlaced optical wiring braid are provided in a module in an optical fiber sheet. In the storage tray provided with the optical fiber sheet, the optical fiber separated into the IP system and the RF system is respectively an optical device of the optical fiber sheet and a plurality of IP systems. And then branching to an RF optical fiber, one IP line and one RF line can be distributed to each subscriber via a braided portion. As a result, it is possible to speed up the connection work and prevent erroneous connection.

  The storage tray is widely applied to optical MDF, optical IDF, optical closure, optical termination box, and the like.

  Further, when the upper system is looped into the main transmission system and the sub-transmission system, an optical device for demultiplexing / multiplexing optical signals, as in the case where the introduction side of the storage tray described above is an IP system and an RF system, The interlaced optical wiring braid is housed as a modular braided body in the optical fiber sheet. Therefore, the storage tray having the optical fiber sheet is separated into a main transmission system and a sub-transmission system. Each of the optical fibers is branched into a plurality of optical fibers of the main transmission system and the sub-transmission system by the optical device of the optical fiber sheet, and then each of the main transmission system and the sub-transmission system 1 per subscriber through the braiding unit. A line can be distributed. As a result, it is possible to speed up the connection work and prevent erroneous connection.

  Embodiments of the present invention will be described below with reference to the drawings.

  First, a cable wiring system to which the optical fiber branching and distributing method according to this embodiment is applied will be described.

  Referring to FIG. 4, when an optical fiber cable 1 sheathed with an optical fiber core consisting of a plurality of optical fiber strands or optical fiber tape cores is laid, a number of termination cables 1A (Termination Cable) Main distribution board (optical MDF: Main Distribution Frame, abbreviated as “MDF”) as an optical fiber concentrator provided in a termination cabinet 5 (Termination Cabinet) in a station 3 such as a telephone station or an access point. In an intermediate wiring board (Optical IDF: Intermediate Distribution Frame, hereinafter abbreviated as “IDF”) or the like, it is connected by an optical connector (not shown).

  Since the optical fiber cable 1 has a limited length, several optical fiber cables 1 are connected and extended. For example, the optical station cable 7 is concentrated by the optical MDF, and the optical station termination cable 1A from the optical MDF is connected to the underground optical cable 1B (Underground Cable) by the termination optical closure 11 in the cable chamber 9. Further, when wiring from the underground optical cable 1B to the utility pole 13, it is wired to the utility pole 13 by the optical riser cable 1C (Riser Cable) connected by the underground light closure 17 in the manhole 15, and the overhead optical cable 1D ( Wired with Aerial Cable).

  Also, each optical fiber of the aerial optical cable 1D is pulled down to a building or a subscriber's house 23 of each ordinary home by an optical fiber drop cable 21 that covers the optical fiber by an aerial optical closure 19, and is used in an indoor OE converter or optical fiber. Connected to the end box.

  For example, in a large building 25 such as an office, a factory, a school, a hospital, or a housing complex, the underground light closure 17 in the manhole 15 is connected to another underground light cable 1E and extended to be in the large building 25. It is wired to the optical termination box 27, and is wired from the optical termination box 27 into each room by the optical indoor cable 29.

  The termination optical cable 1A, the underground optical cable 1B, the optical riser cable 1C, the aerial optical cable 1D, and the underground optical cable 1E are all optical fiber cables 1.

  Referring to FIG. 5, generally, the access optical fiber cable 1 uses a large number of IP optical fiber ribbons 31A and four RF optical fiber ribbons 31B. As an example, for example, the aerial optical fiber cable 1 includes a plurality of layers in a first strength member 35 provided at the center of the slot rod 33 and a plurality of slots 37 arranged around the first strength member 35 as shown in FIG. Optical fiber tape cores 31A and 31B are gathered, and a metal tape 39, for example, as a tape winding is vertically wound around the outer periphery of the slot rod 33, and a sheath 41 such as a sheath resin is wound around the outer periphery of the metal tape 39. A long optical fiber portion 43 configured by being sheathed is provided. Further, a long cable support line portion 49 is provided in which the periphery of the second tensile body 45 as a suspension line is covered with a sheath resin 47. The cable support line portion 49 and the optical fiber portion 43 are connected to the neck portion 51. Are integrated in parallel with each other.

  In addition, as shown in FIG. 6A, the optical fiber drop cable 21 has an optical element portion 53 having, for example, two optical fiber strands 55 (or an optical fiber core wire or an optical fiber tape core wire). And a pair of strength members 57 attached to both sides parallel to the vicinity thereof, which are collectively covered with a cable sheath 59 of a thermoplastic resin such as PVC or flame retardant PE, Notches 61 are formed on the surface of the cable sheath 59 on both sides of the optical fiber strand 55 in a direction orthogonal to the direction in which the strength members 57 are connected.

  Further, a long cable support line portion 67 in which a support wire 63 made of, for example, a steel wire is covered with a sheath material 65 made of the same resin as the cable sheath 59 is parallel to the neck portion 69 of the cable sheath 59 of the optical element portion 53. It is integrated through. In this case, the cable sheath 59 is separated from the cable support line portion 67 at the neck portion 69, and the optical element portion 53 is used as an indoor drop cable as shown in FIG. 6B.

  Referring to FIG. 1, a number of IP-based four-fiber optical fiber ribbons 31A and an RF-based four-fiber optical fiber ribbon 31B in an optical fiber cable 1 are composed of an IP-based optical fiber 55A. And the RF optical fiber 55B are separated from each other. For example, in the aerial optical closure 19, one core of the IP optical fiber strand 55A is branched into a plurality of IP optical fiber strands 55A by an IP optical device 71A composed of an optical coupler, an optical splitter, etc. One core of the RF optical fiber strand 55B is branched into a plurality of RF optical fiber strands 55B by the RF optical device 71B.

  Further, a total of two cores, one for each of the IP system and the RF system, out of the plurality of optical fiber strands 55A and 55B branched by the IP system optical device 71A and the RF system optical device 71B are connected to the optical fiber drop cable 21. Connected with 2 cores. When such a connection is made, a single-core separated IP system and RF optical fiber strands 55A and 55B are combined and connected.

  The aerial optical closure 19 is provided with a storage tray 73 for storing IP and RF optical fiber strands 55A and 55B (or optical fiber core wires). For example, an optical fiber sheet 77 as a knitted body in which a system optical device 71A, an RF system optical device 71B, and a knitted portion 75 in which a plurality of optical fiber strands 55A and 55B (or optical fiber core wires) are crossed are modularized. Is provided. In this embodiment, an optical splitter is used as each of the IP optical device 71A and the RF optical device 71B, and one optical splitter is provided.

  Referring to FIGS. 2 and 3 together, the optical fiber sheet 77 will be described in more detail. FIG. 2 is an enlarged plan view of the optical fiber sheet 77 of FIG. 1, and the left side optical fiber in FIGS. The introduction side 79 includes, for example, one fusion splicing portion reinforcing member 81A as an introduction side connection portion of the IP optical fiber strand 55A and, for example, one location as an introduction side connection portion of the RF optical fiber strand 55B. The fusion splicing portion reinforcing material 81B is provided.

  Of the multiple optical fiber tape cores 31A and 31B of the optical fiber cable 1, one IP optical fiber strand 55A and one RF optical fiber strand 55B are taken out, and the IP optical fiber is extracted. The strand 55A is connected to the fusion splicer reinforcement 81A, and the RF optical fiber strand 55B is connected to the fusion splicer reinforcement 81B.

  Further, in the optical fiber sheet 77, the IP optical device 71A is connected to the fusion splicer reinforcement 81A via the optical fiber strand 55A, and the optical fiber strand 55B is connected to the fusion splicer reinforcement 81B. An RF optical device 71B is connected via One core of the IP optical fiber strand 55A is branched into eight IP optical fiber strands 55A by an IP optical device 71A, and one core of the RF optical fiber strand 55B is split by an RF optical device 71B. Branches to an 8-core RF optical fiber 55B.

  Also, the braided portion 75 of the optical fiber sheet 77 is composed of an 8-core IP optical fiber 55A on the branch side of the IP optical device 71A and an 8-fiber RF optical fiber on the branch side of the RF optical device 71B. 55B is combined with one line for each of the IP system and the RF system for each subscriber via the optical fiber strands 55A and 55B of the braided portion 75 of the optical fiber sheet 77, respectively. The optical fiber distribution side 83 is connected to, for example, eight fusion splicing portion reinforcing members 85A and 85B as distribution side connection portions, and is distributed to a total of eight subscribers.

  Since two cores of the optical fiber drop cable 21 are connected to two cores of one line of the IP system and RF system of the fusion splicing portion reinforcing members 85A and 85B, in FIG. 1 and FIG. A total of eight optical fiber drop cables 21 of eight subscribers are connected to the right optical fiber distribution side 83.

  In the optical fiber sheet 77, as shown in FIG. 3, a plurality of optical fiber strands 55A and 55B are sandwiched by a flexible plastic film 77A from above and below in FIG. 3 and bonded by an adhesive layer 77B. Configured. Each of the optical fiber strands 55A and 55B is obtained by applying a UV resin coating resin 55D to the outer periphery of a bare optical fiber 55C made of, for example, quartz glass.

  In FIG. 2, the arrows indicate the signal directions of the optical signals. In each optical fiber drop cable 21, the IP optical fiber strand 55 is used for the Internet and a telephone to transmit upstream and downstream bidirectional digital signals. At the same time, the RF optical fiber 55 is used for moving images and transmits a high-band signal only in one downstream direction.

  The storage tray 73 is attached to the optical MDF, the optical IDF, the underground light closure 17, the aerial light closure 19, the optical termination box 27, etc. in the termination cabinet 5, as indicated by arrows in FIG. Widely equipped.

  Further, the portion of the optical fiber 55 of the optical fiber sheet 77 described above may be a combination of optical fiber core wires.

  In this embodiment, one IP system optical device 71A and one RF system optical device 71B use a total of two optical devices 71. The number of optical devices 71 is the same as that of the IP system and the RF system. There may be a plurality of systems. Further, the number of branches of the optical device 71 such as an optical coupler or an optical splitter is not particularly limited. Further, the optical fiber sheets 77 on which the optical devices 71 are mounted are not limited to be used one by one in the storage tray 73, and a plurality of optical fiber sheets 77 can be used in the same storage tray 73.

  The above-mentioned matters include the design of optical lines such as the number of optical cable cores, the number of optical cable branches, the number of optical fiber cores, and the number of optical stations and access points in constructing a PON (Passive Optical Network). It can be appropriately selected according to the operation purpose such as maintenance.

  Further, the optical fiber branching and distributing method of this embodiment is not affected by the laying environment such as underground, aerial, bridge portion, and sloping ground. In addition, there are no restrictions on buildings, such as office buildings, buildings, and residential buildings.

  Next, in order to confirm the effect of the optical fiber branch / distribution method according to the embodiment of the present invention, the optical fiber branch / distribution of the following Example 1, Example 2, Comparative Example 1, Comparative Example 2, and Comparative Example 3 will be described. Work was performed and various tests were conducted for installation time, reconnection, and bending properties.

  In addition, as a common condition of each operation | work in Example 1, Comparative example 1, and Comparative example 2, it is the connection operation | work in the optical termination box 27 for apartment houses in FIG. 4, The introduction side of the optical termination box 27 is Two optical fiber drop cables, one of which is an IP system and the other is an RF system. In addition, the distribution side of the optical termination box 27 uses 8 pieces of 2-core in-home wiring cables. That is, in the embodiment described above, the overhead light closure 19 is taken as an example as shown in FIG. 1, but the optical termination box 27 for an apartment house of Example 1, Comparative Example 1, and Comparative Example 2 is basically the same. Since the configuration is the same as that of the aerial light closure 19, common structural members will be described with the same reference numerals as those of the above-described embodiment.

  In the form of the first embodiment, the IP optical device 71A and the RF optical device 71B are respectively an 8-branch optical splitter, and eight IP optical fiber strands 55A and 8 branched from the two 8-branch optical splitters. An optical fiber sheet 77 equipped with a braided portion 75 in which the core RF-based optical fiber strands 55B are converged was used to perform a fusion splicing operation in units of two cores.

That is, a total of two optical fiber strands 55, that is, a single core IP optical fiber strand 55A and a single core RF optical fiber strand 55B, are provided on the optical fiber introduction side 79 of the optical termination box 27. The sheet 77 is connected to, for example, the fusion splicing reinforcements 81A and 81B as the introduction side connecting portion. In the optical fiber sheet 77, one subscriber is connected via the IP optical device 71A and the RF optical device 71B and the braided portion 75. It is combined with each line of IP system and RF system, and distributed to a total of 8 subscribers. The two IP-system and RF-system cores of each line of the eight subscribers are connected to the two cores of the optical fiber drop cable 21 as a home wiring cable by fusion splicing work.
(Comparative Example 1)

In the form of Comparative Example 1, as shown in FIG. 8 as a conventional method, an IP optical device 249A, an RF optical device 249B, and a storage tray provided with a braided portion are used in advance, and a unit of 2 cores is used. Fusion splicing work was performed. At this time, the braided portion is prepared in a storage tray in advance, for example, in a separate place and connected to the IP-based optical device 249A and the RF-based optical device 249B before performing the connection work in the optical termination box for collective housing. Thus, it was not molded as in Example 1.
(Comparative Example 2)

  In the form of Comparative Example 2, as shown in FIG. 9 as a conventional method, the braiding operation was performed without prior preparation, and the fusion splicing operation in units of two cores was performed. That is, at the time of connection work in the optical termination box for collective housing, a total of two cores of the IP system on the branch side of the IP system optical device 249A and the RF system optical device 249B and one core of each of the RF system optical fiber wires 203A and 203B. A fusion splicing operation is performed while producing a braided portion in combination.

The form of Example 2 is an optical fiber sheet 77 equipped with an 8-branch optical splitter manufactured using a single-mode optical fiber having high bending resistance and high resistance to bending according to ITU-T G.652.
(Comparative Example 3)

The form of Comparative Example 3 is an optical fiber sheet 77 equipped with an 8-branch optical splitter manufactured using a normal SM optical fiber (general grade single mode optical fiber).
(Test Example 1)

  The characteristic value of Test Example 1 is laying time.

About Example 1, Comparative example 1, and Comparative example 2, 20 optical termination boxes for apartment houses were used, 20 installations and construction were performed, and the installation time was measured. The results are shown in Table 1 as average values per location. The symbol “←” means the same in the left column.

  As can be seen from Table 1, in the first embodiment, the use of the optical fiber sheet 77 prevents the optical fiber strand 55 from congesting at the time of fusion splicing, so that the workability is excellent and the installation time is shortened. Therefore, Example 1 can be constructed in about half of the laying work time of Comparative Example 2.

Further, in Example 1 and Comparative Example 1, the laying time in the actual field (site) is the same except for the installation work of the optical splitter. However, since Comparative Example 1 requires preparation of a braided portion and installation of an optical splitter as advance preparation, Example 1 is superior in overall installation time.
(Test Example 2)

  The characteristic value of Test Example 2 is the amount of change in transmission loss of the live wire after reconnection. Note that reconnecting means disconnecting an already connected device once and reconnecting it to another core wire.

About Example 1, Comparative Example 1, and Comparative Example 2, the optical fiber strands were reconnected using the optical termination boxes for 20 apartment buildings that had already been laid and constructed, and the working time Also, the amount of change in transmission loss of an optical fiber (hot wire) other than the optical fiber was measured. The results are shown in Table 2. The symbol “←” means the same in the left column.

  As can be seen from Table 2, an optical fiber sheet 77 having an 8-branch optical splitter and a braided portion 75 as in Example 1 is used rather than taking out a congested optical fiber as in Comparative Example 2 and performing reconnection. It is obvious that a simple reconnection operation using a braided portion provided in advance as in Comparative Example 1 has a shorter operation time. Therefore, the working time of Example 1 / Comparative Example 1 and Comparative Example 2 is about half.

  Moreover, in any of Example 1, Comparative Example 1, and Comparative Example 2, it is inevitable that a considerable external force is applied to the live wire during the reconnection work.

  The problem is the amount of change in transmission loss when an external force is applied. If this amount of fluctuation is sufficiently small, it is considered that there is no effect on the actual transmission, but if it becomes a certain size, there is a possibility that the actual transmission will be hindered.

In this respect, as shown in Table 2, it can be seen that the effect of Example 1 is greater than that of Comparative Example 1 and Comparative Example 2.
(Test Example 3)

  Test Example 3 is a test for bending characteristics, and the measured value is a change in transmission loss (unit: dB).

  About Example 2 and Comparative Example 3, a bending test was performed based on JIS C 6851 (optical fiber cable characteristic test method). As shown in FIG. 7, the optical fiber sheet 77 as the sample 89 is one end side of a bending arm 93 whose one end side swings up and down around the vibration shaft 91 as the bending test apparatus 87. The other end of the sample 89 is bent at 90 degrees by a bending member 97 having a bending radius R (R = 15 mm), and a tensile load is applied to the other end of the sample 89 by a weight 99. In this way, the sample 89 is bent 180 degrees backward and forward with a tensile load applied. That is, one cycle is a period from when the sample 89 is bent to the right most from the vertical position, then shaken to the leftmost position, and then returned to the first vertical position. The bending speed is 1 cycle for about 2 seconds.

  For each of the optical fiber sheets 77 of Example 2 and Comparative Example 3, the bending loss at each number of bendings when the number of 90-degree bending cycles was increased was measured. The results are shown in Table 3.

  Table 3 also shows the results of the temperature characteristic test (−40 ° C. to + 70 ° C.) of each optical fiber sheet 77 when 90-degree bending (bending radius R = 15 mm) was performed 50 times.

  The number of samples N in Example 2 and Comparative Example 3 is N = 10. Moreover, the optical fiber which comprises the sample 89 (optical fiber sheet 77) of Example 2 is ITU-TG. An international standard optical fiber based on 652, that is, an optical fiber resistant to bending was used. An ordinary SM type optical fiber was used as an optical fiber constituting the sample 89 (optical fiber sheet 77) of Comparative Example 3.

Incidentally, the mode field diameter (core diameter) of the optical fiber of Example 2 is smaller than that of the SM type optical fiber of Comparative Example 3, and the refractive index difference of the optical fiber of Example 2 is the same as that of the SM type optical fiber of Comparative Example 3. It is big compared.

  As can be seen from Table 3, the bending-resistant optical fiber constituting the sample 89 of Example 2 was bent in the optical fiber sheet 77 rather than the SM type optical fiber constituting the sample 89 of Comparative Example 3. Obviously, the amount of change in transmission loss is small. Furthermore, in the temperature characteristic test, it is known that an external force is applied to the optical fiber core wire due to a difference in linear expansion coefficient with the constituent material of the optical fiber sheet 77. Even when there is a change in temperature, it is clear that the amount of change in transmission loss is smaller in an optical fiber that is resistant to bending.

  In addition, as described in Patent Document 8 described above, for example, a carbon-coated optical fiber is used as a conventional optical fiber sheet as an optical fiber wire constituting the optical fiber sheet. Such an optical fiber is more expensive than a normal optical fiber. In addition, ITU-T G.I. Unless it is an international standard optical fiber compliant with 652, it is difficult to actually use it as a transmission line for public communication.

  Incidentally, the conventional optical fiber sheet of Patent Document 8 described above is different from the configuration of the optical fiber sheet 77 of this embodiment in terms of purpose, action, and effect.

  From the above, in the optical fiber branching and distributing method of this embodiment, the optical devices 71A and 71B for demultiplexing / multiplexing the optical signal and the interlaced optical wiring braid 75 are preliminarily provided in the optical fiber sheet 77. By storing the optical fiber sheet 77 in advance in a storage tray 73 such as an optical MDF, optical IDF, underground light closure 17, each optical closure, optical termination box 27, etc. The optical fiber strands 55A and 55B separated into the IP and RF systems are branched into a plurality of IP and RF optical fiber strands 55A and 55B by the optical devices 71A and 71B of the optical fiber sheet 77. After that, one line for each of the IP system and the RF system can be branched and distributed per subscriber via the braiding unit 75.

  As a result, the optical fiber strands 55A and 55B are not congested, and the optical fiber strands 55A and 55B are not entangled and unnecessary external force is applied, thereby preventing an increase in transmission loss and preventing erroneous connection. Furthermore, speeding up of the connection work can be achieved and the work time can be shortened, which is effective in reducing the laying cost.

  In addition, each time an end user applies or cancels, the optical fiber strands 55A and 55B are taken out and connected, or the connection of the optical fiber strands 55A and 55B is released as in the conventional case. It becomes unnecessary to take out the optical fiber strands 55A and 55B from the congested optical fiber strands 55A and 55B, and the live wires (optical fiber strands 55A and 55B) are not affected.

  In the above-described embodiment, it is assumed that two types of transmission, that is, the IP system and the RF system, are performed. However, the present invention is not limited to the IP system and the RF system.

  For example, a case where transmission only for the IP system is described as an example. When the upper system of this IP system is looped into the main transmission system and the sub-transmission system, in FIGS. 1 and 2 of the above-described embodiment. The IP optical fiber 55A is replaced with a main transmission optical fiber, and the RF optical fiber 55B is replaced with a sub transmission optical fiber. Furthermore, by replacing the IP optical device 71A with the main transmission optical device and replacing the RF optical device 71B with the sub transmission optical device, the main transmission system and the sub transmission system can be distributed to a plurality of lines. .

  That is, the optical fiber strand of the main transmission system is connected to the introduction side of the main transmission optical device, and the optical fiber strand of the sub transmission system is connected to the introduction side of the sub transmission optical device. A plurality of optical fibers branched by the respective optical devices of the main transmission system and the sub-transmission system are braided portions corresponding to the braided portion 75 described above, and the distribution side of the optical fiber sheet corresponding to the optical fiber sheet 77 as the braided body This is also effective when distributing one line each for the main transmission system and the sub-transmission system per subscription.

  Looping the above-described upper system is a method generally performed in an optical line. This is particularly effective when there is an important line or when it is difficult to stop the line. That is, when an optical network is formed in a loop shape and a failure occurs in a certain place in the loop, transmission by a detour route is possible. The failure here is due to a natural disaster or the like, for example, the optical cable is broken, the operator's human error etc., for example, the optical fiber core wire is broken, the change of the loop due to trouble transfer, etc. It means a part of line stoppage or machine failure for maintenance / maintenance purposes.

  For example, normally, when transmission is performed in the main transmission system, for example, in the clockwise route of the loop, if some kind of failure occurs (including cases where it is known in advance or suddenly), this time For example, the sub-transmission system can take a detour to the left-hand route of the loop, so that transmission can be continued.

  Although the embodiment of the present invention relates to an optical network, the above point is strictly related to an instantaneous power failure response function and a switching function of a transmission device.

It is a schematic explanatory drawing of the optical fiber branch distribution state in the aerial optical closure in embodiment of this invention. 1 is a schematic plan view of an optical fiber sheet used in an embodiment of the present invention. It is sectional drawing of the arrow III-III line | wire of FIG. 1 is a schematic explanatory diagram of a cable wiring system to which an optical fiber branching and distributing method according to an embodiment of the present invention is applied. It is sectional drawing of an aerial optical fiber cable. (A) is sectional drawing of an optical fiber drop cable, (B) is sectional drawing of an indoor drop cable. It is a schematic explanatory drawing of a bending test apparatus. It is a schematic explanatory drawing of the optical fiber branch distribution state in the conventional aerial optical closure. It is a schematic explanatory drawing of the other optical fiber branch distribution state in the conventional aerial optical closure. It is sectional drawing of the conventional aerial optical fiber cable. (A) is sectional drawing of the optical fiber drop cable in FIG. 10, (B) is sectional drawing of an indoor drop cable.

Explanation of symbols

1, 1A to 1E Optical fiber cable 5 Termination cabinet 17 Underground optical closure 19 Aerial optical closure 21 Optical fiber drop cable 27 Optical termination box 29 Optical indoor cables 31A and 31B Optical fiber tape cores 55A and 55B Optical fiber strand 71A IP optical device 71B RF optical device 73 Storage tray 75 Braided portion 77 Optical fiber sheet 77A Flexible plastic film 77B Adhesive layer 79 Optical fiber introduction side 81A, 81B Fusion splicing portion reinforcement (introduction side connection portion)
83 Optical fiber distribution side 85A, 85B Fusion splice reinforcement (distribution splice)

Claims (15)

  When connecting a plurality of optical fibers in the storage tray, one or a plurality of IP optical devices branch from the IP optical fiber to the plurality of optical fibers, and the RF optical fiber to the plurality of optical fibers in advance. The storage tray includes a knitted body obtained by modularizing one or a plurality of RF optical devices that are branched and a knitted portion that crosses a plurality of optical fibers that are branched by the IP and RF optical devices. An optical fiber separated into an IP system and an RF system is connected to the introduction side of each of the IP system and RF system optical devices of the braided body, and a plurality of optical fibers branched by the IP system and RF system optical devices are connected An optical fiber branching and distributing method characterized in that one line each of an IP system and an RF system is distributed per subscriber to the distribution side of a braided body at the braiding unit.   The optical fiber branching and distributing method according to claim 1, wherein the braided body is an optical fiber sheet including the IP and RF optical devices and the braided portion.   The optical fiber branching and distributing method according to claim 1 or 2, wherein the storage tray is provided in any of an optical MDF, an optical IDF, an optical closure, and an optical termination box.   4. The optical fiber branch distribution according to claim 1, wherein only the changed line is reconnected from the plurality of lines with little external force applied to a live line other than the changed line during reconnection. Method.   The optical fiber is ITU-T G.264. The optical fiber branching and distributing method according to any one of claims 1 to 4, wherein the optical fiber is a highly flexible optical fiber conforming to the international standard of 652.   When connecting a plurality of optical fibers in the storage tray, if the host system is looped into the main transmission system and the sub-transmission system, one or more branches in advance from the optical fiber of the main transmission system to the plurality of optical fibers A main transmission system optical device, one or a plurality of sub transmission system optical devices branching from the sub transmission system optical fiber to a plurality of optical fibers, and the main transmission system and sub transmission system optical devices. The storage tray is provided with a knitted body obtained by modularizing a plurality of optical fibers that are crossed, and an optical fiber separated into a main transmission system and a sub-transmission system. A plurality of optical fibers connected to the introduction side of each optical device in the transmission system and branched by the respective optical devices in the main transmission system and the sub-transmission system are mainly distributed per subscriber to the distribution side of the braided body in the braiding unit. Transmission system, sub-transmission system Optical fiber branching distribution wherein the distributing each one line.   7. The optical fiber branching and distributing method according to claim 6, wherein the braided body is an optical fiber sheet including the optical devices of the main transmission system and the sub-transmission system and the braided portion.   The optical fiber branching and distributing method according to claim 6 or 7, wherein the storage tray is provided in any of an optical MDF, an optical IDF, and an optical closure optical termination box.   9. The optical fiber branch distribution according to claim 6, 7 or 8, wherein only the changed line is reconnected without applying an external force to a live line other than the changed line from among a plurality of lines during reconnection. Method.   The optical fiber is ITU-T G.264. 10. The method of branching and distributing an optical fiber according to claim 6, wherein the optical fiber is a highly flexible optical fiber conforming to the international standard of 652.   A plurality of introduction side connection portions for connecting one or a plurality of optical fibers of the IP system and one or a plurality of optical fibers of the RF system on the optical fiber introduction side, and the IP system and the RF per subscriber on the optical fiber distribution side A plurality of distribution side connection parts for distributing each one line of the system; one or a plurality of IP type optical devices branching from an IP type optical fiber conducting to the introduction side connection part to a plurality of optical fibers; and the introduction Crossing one or a plurality of RF optical devices branching from an RF optical fiber conducting to the side connection portion into a plurality of optical fibers, and a plurality of optical fibers branched by each of the IP and RF optical devices A knitting unit that distributes one line for each of the IP system and the RF system for each subscriber and conducts to each of the distribution side connection units, and each of the IP and RF system optical devices and the knitting unit as a module. To get into contact Optical fiber sheet, wherein the resin film of two to fix through the adhesive layer to become configured from.   The optical fiber is ITU-T G.I. The optical fiber sheet according to claim 11, wherein the optical fiber sheet is a highly flexible optical fiber conforming to the international standard of 652. In a storage tray provided in any of optical MDF, optical IDF, optical closure, and optical termination box,
A plurality of introduction side connection portions for connecting one or a plurality of optical fibers of the IP system and one or a plurality of optical fibers of the RF system on the optical fiber introduction side, and the IP system and the RF per subscriber on the optical fiber distribution side A plurality of distribution side connection parts for distributing each one line of the system, and one or a plurality of IP type optical devices branching from the IP type optical fiber conducting to the introduction side connection part to the plurality of optical fibers; , One or a plurality of RF optical devices branching from an RF optical fiber conducting to the introduction-side connecting portion to a plurality of optical fibers, and a plurality of lights branched by the IP optical devices and the RF optical devices. A braided portion that crosses fibers and distributes one line of each of the IP and RF systems per subscriber and conducts to each of the distribution side connecting portions; and each of the IP and RF optical devices and the braided portion And modularized Storage tray, characterized in that a narrowing seen the body.   The braided body is an optical fiber sheet in which the optical device of the IP system and the RF system and the braided portion are sandwiched between two resin films so as to be modularized and fixed through an adhesive layer. The storage tray according to claim 13. The optical fiber is ITU-T G.I. The storage tray according to claim 13 or 14, wherein the storage tray is a highly flexible optical fiber compliant with the international standard of 652.

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