JP4372057B2 - PON system station installation method - Google Patents

Description

  TECHNICAL FIELD The present invention relates to a method for installing a PON system station device, and in particular, a method for installing a PON system station device suitable for connecting a plurality of subscriber devices by branching a plurality of optical fibers in a receiving station. About.

  As one of the Internet providing methods, there is a PON (Passive Optical Network) method in which an optical network is constructed by branching one optical fiber into a plurality of pieces in order to effectively use an optical fiber.

  Regarding a conventional station apparatus installation method in the PON system (hereinafter referred to as “PON system station apparatus installation method”), two station apparatuses each having two optical interfaces having 1 to 32 ch channels. An example in which optical fibers are wired up to eight 16-branch splitters installed on the track so that 128 subscriber devices can be connected will be described with reference to FIG.

  The first and second station devices 111 and 112 and the first to fourth two-branch splitters 121 to 124 are installed as equipment in the communication station, and the first to eighth 16-branch splitters 131 to 138 are installed. Install on the track.

  One optical fiber to which 1 to 32 ch of one optical interface (first optical interface) of the first station apparatus 111 is allocated is assigned to the first two-branch splitter 121 by the first allocated channel range. The optical fiber is branched into one optical fiber having 1 to 16 channels of the optical interface and one optical fiber having an assigned channel range of 17 to 32 channels of the first optical interface. Then, one optical fiber whose assigned channel range is 1 to 16 ch of the first optical interface is branched from the first core wire to the 16th core wire by the first 16 branch splitter 131. Further, one optical fiber whose assigned channel range is 17 to 32 ch of the first optical interface is branched from the first core wire to the 16th core wire by the second 16-branch splitter 132.

  One optical fiber to which channels 1 to 32ch of the other optical interface (second optical interface) of the first station apparatus 111 are assigned is assigned to the second two-branch splitter 122 so that the assigned channel range is second. The optical fiber branches into one optical fiber that is 1 to 16 ch of the optical interface and one optical fiber that has an assigned channel range of 17 to 32 ch of the second optical interface. Then, one optical fiber whose assigned channel range is 1 to 16 ch of the second optical interface is branched from the first core wire to the 16th core wire by the third 16-branch splitter 133. In addition, one optical fiber whose assigned channel range is 17 to 32 ch of the second optical interface is branched from the first core line to the 16th core line by the fourth 16-branch splitter 134.

  One optical fiber to which 1 to 32 ch of one optical interface (third optical interface) of the second station apparatus 112 is assigned is assigned to an assigned channel range of 1 to 16 ch by the third two-branch splitter 123. And one optical fiber having an assigned channel range of 17 to 32 ch. Then, one optical fiber whose assigned channel range is 1 to 16 ch of the third optical interface is branched from the first core wire to the 16th core wire by the fifth 16 branch splitter 135. In addition, one optical fiber whose assigned channel range is 17 to 32 ch of the third optical interface is branched from the first core wire to the 16th core wire by the sixth 16-branch splitter 136.

  One optical fiber to which channels 1 to 32 of the other optical interface (fourth optical interface) of the second station apparatus 112 are allocated is assigned to an allocated channel range of 1 to 16 by the fourth two-branch splitter 124. And one optical fiber having an assigned channel range of 17 to 32 ch. Then, one optical fiber whose assigned channel range is 1 to 16 ch of the fourth optical interface is branched from the first core wire to the 16th core wire by the seventh 16-branch splitter 137. In addition, one optical fiber whose assigned channel range is 17 to 32 ch of the fourth optical interface is branched from the first core wire to the 16th core wire by the eighth 16-branch splitter 138.

  As described above, in the conventional method for installing the PON system station apparatus, as shown in FIG. 8, the first optical interface 1 to 32 ch, the second optical interface 1 to 32 ch, and the third optical interface 1 to 32 ch and the fourth optical interface 1 to 32 ch are all assigned to subscriber devices connected to the cores branched from the first to eighth 16-branch splitters 131 to 138, respectively.

  That is, in the conventional method for installing a PON system station device, only N M-branch splitters are installed on the line so that N × M subscriber devices can be connected, and a plurality of station devices are used. From the beginning of constructing an optical network, a plurality of station devices have been installed as equipment in a communication station so that channels can be allocated to N × M subscriber devices from the device.

In Patent Document 1 below, a device-side optical fiber optically connected to a transmission device is accommodated in a coupler so that an optical fiber can be efficiently and economically added in response to an increase in the number of users. The optical fiber branches into a plurality of external optical fibers via a station optical coupler housed in the section, and each of the optical fibers is routed to a distribution optical coupler housed in an optical junction box. In an optical transmission system in which a plurality of distribution optical fibers are branched by a distribution optical coupler and each of these distribution optical fibers is routed to a terminal, a plurality of types of station-side optical couplers having different branch numbers are provided in the coupler housing. An optical wiring method in which the number of distribution optical couplers and the number of branches that are optically connected to one transmission device via a station-side optical coupler are different depending on the number of branches of each station-side optical coupler. It is disclosed.
JP 2005-17519 A

  However, in the above-described conventional method for installing a PON station device, a plurality of station devices are used as equipment in a communication station so that a channel can be allocated to all N × M subscriber devices. Since it was installed from the beginning of construction, there was a problem that the initial investment of the equipment in the communication station building was large.

  An object of the present invention is to provide a method for installing a PON system station apparatus that can greatly reduce the initial investment of equipment in a communication station building and the space for accommodating communication equipment.

Installation of PON type for station apparatus of the present invention is to set up the M N branch splitter (31-38) to the line path to be able to connect the N × M pieces of subscriber equipment, a plurality When constructing a PON optical network by assigning one channel at a time from each of the station devices (11, 12) to the N × M subscriber devices, the plurality of station devices are connected to a communication station. This is a method of installing a PON system station apparatus used for installation as an internal facility, and initially has a small number of subscribers when constructing the PON optical network, and the M N-branch splitters (31 to 38) One channel is allocated to at least one subscriber unit connected to each of the N branching splitters, and only one channel is allocated to a total of (N × M) / (multiple of 2) subscriber units. When it is sufficient assignment, the among the plurality of central office equipment, (N × M) / ( 2 multiples) pieces of subscriber equipment office equipment necessary number to assign channels one by one only (11) only with installing as the communication station building facilities,
At least one L branch splitter (21, 22) for connecting the necessary number of station devices (11) and all of the M N branch splitters (31 to 38) via optical fibers At least one subscriber unit installed as equipment in a communication station and connected to each N branch splitter of the M N branch splitters (31 to 38) from the required number of station devices (11). Channels are allocated one by one, and only one channel is allocated to each of the total of (N × M) / (multiple of 2) subscriber devices, and then the PON optical network is constructed. As the number increases, the number of subscriber devices connected to at least one N-branch splitter among the M N-branch splitters (31 to 38) increases, and the required number of station devices 11) If it becomes impossible to allocate a channel only, another station device (12) among the plurality of station devices is newly installed as equipment in the communication station, and the number of subscribers is small. It is characterized in that the number of station devices to be installed as equipment in a communication station at the beginning of constructing the PON optical network is reduced .
Here, at least one (L / (multiple of 2)) branching splitter (41, 42) is newly installed as communication station equipment together with the other station apparatus (12), and the connected subscribers are connected. At least one N-branch splitter and the other station device (12) having a larger number of user devices are connected via the at least one (L / (multiple of 2)) branch splitter (41, 42). May be assigned to each of N subscriber devices connected to the at least one N-branch splitter from the other station device (12) one by one.
When the other station device (12) is newly installed as a communication station facility, at least one other (L / (multiple of 2)) splitter is newly installed as a communication station facility. From the required number of station devices (11) through the at least one other (L / (multiple of 2)) branching splitter and from the other station devices (12) Channels may be assigned to the N × M subscriber units one by one via at least one (L / (multiple of 2)) splitter (41, 42).
When the plurality of station devices (12) are all installed as equipment in a communication station, the at least one L branch splitter (21, 22) is connected to the at least one other (L / (2 Multiple))) may be replaced with a branching splitter.
When the plurality of station devices have overlapping channels, the overlapping channels are not assigned to N subscriber devices respectively connected to the M N branch splitters. One channel may be allocated to each of the N × M subscriber apparatuses from a plurality of station apparatuses.
When one station apparatus (11) of the required number of station apparatuses includes two optical interfaces having overlapping channels, the PON optical network is constructed. Initially, two L-branch splitters (21, 22) are installed as equipment in the communication station, and one of the one station device (11) and the two L-branch splitters (21, 22) One L-branch splitter (21) is connected via an optical fiber to which a channel of one of the two optical interfaces is assigned, and the one station apparatus (11). And the other L branch splitter (22) of the two L branch splitters (21, 22) are connected to the other optical interface of the two optical interfaces. Tunnels may be connected via an optical fiber the assigned.
When the other station device (12) is provided with two other optical interfaces having overlapping channels, the other station device (12) is newly added as a communication station facility. When installed, two (L / (multiple of 2)) branching splitters (41, 42) are newly installed as equipment in the communication station, and the other station device (12) and the two One (L / (multiple of 2)) branch splitter (41) of the (L / (multiple of 2)) branch splitters (41, 42) is connected to one of the two other optical interfaces. The other station (12) and the two (L / (multiple of 2)) branch splitters (41, 42) are connected to each other through the optical fiber to which the channel of the other optical interface is assigned. ) The other one (L / (multiple of 2)) And Toki splitter (42) may be connected via the other of another optical fiber channel is assigned the optical interface of the two other optical interface.

  The method for installing the PON system station apparatus according to the present invention is such that, even when M N-branch splitters are installed on a line and N × M subscriber apparatuses are connected, an optical network is initially constructed (N × M) / (Multiple of 2) Since only the number of station devices necessary for allocating channels to each subscriber device need to be installed as equipment in the communication station, Initial investment and communication equipment storage space can be greatly reduced.

  At the beginning of the construction of the optical network, (N × M) / (multiple of 2) subscriptions out of N × M subscriber units, with the objective of significantly reducing the initial investment in equipment in the communication station This was realized by installing only the number of station devices necessary for assigning channels only to the user devices as the equipment in the communication station.

Embodiments of a method for installing a PON station apparatus according to the present invention will be described below with reference to the drawings.
According to one embodiment of the present invention, a method for installing a PON system station apparatus includes 8 (M = 8) installed on a line from two station apparatuses each including two optical interfaces each having 1 to 32 ch channels. The optical fiber is wired up to 16 branch splitters (N branch splitter: N = 16) so that 128 (= N × M) subscriber devices can be connected.

  In the PON system station installation method according to the present embodiment, at the beginning of constructing the optical network, 64 (= (N × M) / 2) of 128 (= N × M) subscriber units. Only one station device necessary for assigning a channel only to each subscriber device is installed as equipment in the communication station.

  That is, as shown in FIG. 1, station equipment 11 having first and second optical interfaces each having 1 to 32 ch channels, and first and second four-branch splitters as equipment in a communication station (L branch splitter: L = 4) 21 and 22 are installed.

  Then, one optical fiber to which channels 1 to 32 of the first optical interface of the station apparatus 11 are allocated is assigned by the first four-branch splitter 21 so that the allocated channel range is 1 to 8 channels of the first optical interface. One optical fiber, one optical fiber whose assigned channel range is 9 to 16 ch of the first optical interface, and one optical fiber whose assigned channel range is 17 to 24 ch of the first optical interface Then, the assigned channel range branches to one optical fiber having 25 to 32 ch of the first optical interface.

  One optical fiber whose assigned channel range is 1 to 8 ch of the first optical interface is branched from the first core wire to the 16th core wire by the first 16-branch splitter 31. One optical fiber whose assigned channel range is 9 to 16 ch of the first optical interface is branched from the first core line to the 16th core line by the second 16-branch splitter 32. One optical fiber whose assigned channel range is 17 to 24 ch of the first optical interface is branched from the first core wire to the 16th core wire by the third 16-branch splitter 33. One optical fiber having an allocated channel range of 25 to 32 ch of the first optical interface is branched from the first core line to the 16th core line by the fourth 16-branch splitter 34.

  In addition, one optical fiber to which channels 1 to 32 of the second optical interface of the station apparatus 11 are allocated is allocated to the channel range 1 to 8 of the second optical interface by the second four-branch splitter 22. One optical fiber, one optical fiber whose assigned channel range is 9 to 16 ch of the second optical interface, and one optical fiber whose assigned channel range is 17 to 24 ch of the second optical interface Then, the assigned channel range branches to one optical fiber having 25 to 32 ch of the second optical interface.

  One optical fiber whose assigned channel range is 1 to 8 ch of the second optical interface is branched from the first core line to the 16th core line by the fifth 16-branch splitter 35. One optical fiber whose assigned channel range is 9 to 16 ch of the second optical interface is branched from the first core wire to the 16th core wire by the sixth 16-branch splitter 36. One optical fiber whose assigned channel range is 17 to 24 ch of the second optical interface is branched from the first core wire to the 16th core wire by the seventh 16-branch splitter 37. One optical fiber having an allocated channel range of 25 to 32 ch of the second optical interface is branched from the first core line to the 16th core line by the eighth 16-branch splitter 38.

  In this case, although 16 subscriber devices can be connected to the first to eighth 16-branch splitters 31 to 38, respectively, the inputs of the first to eighth 16-branch splitters 31 to 38 are input. Since only 8 channels are assigned to each of the optical fibers connected to the side, the channel can only be assigned to only 8 subscriber devices. However, there is no particular problem because the number of subscribers is small at the beginning of the construction of the optical network.

  As described above, in the method of installing the PON system station apparatus according to the present embodiment, as shown in FIG. 2, the first to fourth 16th channels of the first optical interface of the station apparatus 11 are assigned to the first to fourth 16th channels. Allotted only to the subscriber units connected to 8 of the 16 cores (1st to 16th cores) branched from the splitters 31 to 34, respectively, and Of the 16 core wires (the 1st core wire to the 16th core wire) branched from the first to 32nd channel of the second optical interface of the device 11 from the fifth to eighth 16 branch splitters 35 to 38, respectively. Only the subscriber devices connected to the eight core wires are assigned.

  Thereafter, the number of subscribers increases in the area where the first and seventh 16-branch splitters 31 and 37 are installed, and eight or more channels are required (that is, the station device 11 alone is one of 128 subscriber devices). As shown in FIG. 3, another station apparatus 12 having the third and fourth optical interfaces respectively having channels 1 to 32ch can be assigned to any one subscriber apparatus). And one optical fiber to which channels 1 to 32 of the third optical interface of the other station apparatus 12 are allocated, and one optical fiber and channel having a channel allocation range of 1 to 16 channels of the third optical interface. The first two-branch splitter for branching to one optical fiber whose allocation range is 17 to 32 ch of the third optical interface 1 ((L / 2) branching splitter: L = 4) and one optical fiber to which channels 1 to 32ch of the fourth optical interface of the other station apparatus 12 are assigned. A second two-branch splitter 42 ((L / L) for branching to one optical fiber having 1 to 16 channels of the interface and one optical fiber having a channel allocation range of 17 to 32 channels of the fourth optical interface. 2) A splitter splitter: L = 4) is newly installed as equipment in the communication station.

  And, as shown by the dotted line in FIG. 3, the end of the optical fiber whose channel allocation range is 1 to 8 ch of the first optical interface is removed from the first four-branch splitter 21, Connect to the newly installed first two-branch splitter 41. Similarly, the end of the optical fiber whose channel allocation range is 17 to 24 ch of the second optical interface is removed from the second four-branch splitter 22 and the newly installed first 2 Connect to branch splitter 41.

  Also, as shown in the bottom table of FIG. 4, the channel assignment range of the optical fiber that is disconnected from the first four-branch splitter 21 and connected to the first two-branch splitter 41 is set to 1 to 1 of the first optical interface. The channel number is changed from 8 ch to 1 to 16 ch of the third optical interface of another newly installed station apparatus 12. Similarly, the channel allocation range of the optical fiber disconnected from the second four-branch splitter 22 and connected to the first two-branch splitter 41 is for other newly installed stations from 17 to 24ch of the second optical interface. Change to 17 to 32 ch of the third optical interface of the device 12.

  In addition, 1-8ch of the 1st optical interface of the apparatus 11 for a station which is the original channel allocation range of the optical fiber removed from the 1st 4 branch splitter 21, and it removed from the 2nd 4 branch splitter 22 17 to 24ch of the second optical interface of the station apparatus 11 which is the initial channel allocation range of the optical fiber is an empty channel as shown in the uppermost and middle table of FIG.

  Thereafter, when the number of subscribers increases in the area where the second, fourth, fifth, and sixth 16-branch splitters 32, 34, 35, and 36 are installed and 8 or more channels are required, the following processing is performed. Done.

  For the fourth 16-branch splitter 34, as shown by the dotted line in FIG. 5, the end of the optical fiber whose channel allocation range is 25 to 32 ch of the first optical interface is shown in FIG. Disconnect from the 4-branch splitter 21 and connect to the second 2-branch splitter 42. Similarly, for the fifth 16-branch splitter 35, the end of the optical fiber whose channel allocation range is 1 to 8 ch of the second optical interface on the communication station equipment side is removed from the second 4-branch splitter 22. To the second two-branch splitter 42.

  Further, as shown in the bottom table of FIG. 6, the channel allocation range of the optical fiber that is disconnected from the first four-branch splitter 21 and connected to the second two-branch splitter 42 is defined as 25 to 25 of the first optical interface. The channel number is changed from 32 ch to 17 to 32 ch of the fourth optical interface of the other station apparatus 12. Similarly, the channel assignment range of the optical fiber that is disconnected from the second four-branch splitter 22 and connected to the second two-branch splitter 42 is changed from 1 to 8ch of the second optical interface to the first of the other station devices 12. It changes to 1-16ch of 4 optical interfaces.

  For the second 16-branch splitter 32, the channel allocation range of the optical fiber (shown by a one-dot chain line in FIG. 5) connected to the second 16-branch splitter 32 is shown in the uppermost table of FIG. As described above, the first optical interface is changed from 9 to 16 ch to 1 to 16 ch of the first optical interface. Similarly, for the sixth 16-branch splitter 36, the channel assignment range of the optical fiber (shown by a one-dot chain line in FIG. 5) connected to the sixth 16-branch splitter 36 is shown in the second table of FIG. As shown in FIG. 9, the second optical interface is changed from 9 to 16 ch to the second optical interface from 1 to 16 ch.

  As a result, since only two optical fibers are connected to the 16-branch splitter in the first and second 4-branch splitters 21 and 22, a third and fourth 2-branch splitter (not shown) is newly added. The two optical fibers connected to the first four-branch splitter 21 are removed from the first four-branch splitter 21 and connected to the newly installed third two-branch splitter. The two optical fibers connected to the four-branch splitter 22 are disconnected from the second four-branch splitter 22 and connected to the newly installed fourth two-branch splitter.

  Further, the channel allocation range of the optical fiber connected from the newly installed third 2-branch splitter to the third 16-branch splitter 33 is shown in the uppermost table of FIG. Change from 17 to 24 ch to 17 to 32 ch of the first optical interface. Similarly, the channel assignment range of the optical fiber connected from the newly installed fourth two-branch splitter to the eighth sixteen-branch splitter 38 is shown in the second table of FIG. The interface is changed from 25 to 32 ch to 17 to 32 ch of the second optical interface.

In the above description, 64 (= (N × M) / 2) subscribers out of 128 subscriber units connected to 8 (M = 8) 16-branch splitters (N = 16). Initially, the first and second 4-branch splitters 21 and 22 were installed as equipment in the communication station so that channels were allocated only to the devices, but they can be serviced as described below. The number of new subscriber devices may be increased by a multiple of two.
(1) 64 (= (N × M) / (2 × 2)) subscriptions out of 256 subscriber units connected to 16 (M = 16) 16 branch splitters (N = 16) Instead of the first and second four-branch splitters 21 and 22, first and second eight-branch splitters are installed so that channels can be assigned only to the user devices.
(2) 64 of 512 subscriber devices connected to 32 (M = 32) 16 branch splitters (N = 16) (= (N × M) / (2 × 2 × 2)) Instead of the first and second four-branch splitters 21 and 22, the first and second 16-branch splitters are installed so that the channels are assigned only to the subscriber devices.

  Further, the case where a 16-branch splitter is installed on the line has been described as an example. However, for example, when an 8-branch splitter and a 32-branch splitter are installed, N × M at the beginning of constructing an optical network in the same manner. Only the number of station devices necessary for allocating channels only to (N × M) / (multiple of 2) subscriber devices among the subscriber devices are installed as equipment in the communication station. You can just leave it.

  Furthermore, as shown in FIG. 2, at the beginning of the construction of the optical network, the channel allocation range of the four optical fibers branched by the same four-branch splitter is set to 8 consecutive channels. It does not have to be.

  Furthermore, as shown in FIG. 2, at the beginning of the construction of the optical network, the channel allocation range of the four optical fibers branched by the same four-branch splitter is set to 8 channels each, but a 16-branch splitter is installed. Depending on the number of subscribers at the beginning of the construction of the optical network in the area, the number of channels in the channel allocation range of these four optical fibers may be changed.

  As described above, the PON system station installation method of the present invention can be used, for example, to connect a plurality of subscriber apparatuses by branching one optical fiber into a plurality of branches in the accommodation station. .

It is a figure for demonstrating the installation method of the apparatus for PON system stations by one Example of this invention. Example 1 It is a figure which shows the relationship between the 1st thru | or 8th 16 branch splitters 31-38 shown in FIG. 1, and an allocation channel range. Example 1 It is a figure for demonstrating the change of the connection of an optical fiber and the allocation channel range when another station apparatus is newly installed in the station apparatus installation method by one Example of this invention. Example 1 It is a figure which shows the relationship between the 1st thru | or 8th 16 branch splitters 31-38 after the change shown in FIG. 3, and an allocation channel range. Example 1 It is a figure for demonstrating the change of the connection of an optical fiber, and the allocation channel range after newly installing another station apparatus in the installation method of the station apparatus by one Example of this invention. Example 1 It is a figure which shows the relationship between the 1st thru | or 8th 16 branch splitters 31-38 after the change shown in FIG. 5, and an allocation channel range. Example 1 It is a figure for demonstrating the installation method of the apparatus for stations in the conventional PON system. It is a figure which shows the relationship between the 1st thru | or 8th 16 branch splitters 131-138 shown in FIG. 7, and an allocation channel range.

Explanation of symbols

11 station apparatus 12 other station apparatuses 21, 22 4 branch splitters 31 to 38 16 branch splitter 41, 42 2 branch splitter

Claims (7)

The N × with, from a plurality of service unit (11, 12) the M N branch splitters (31-38) to be able to connect the N × M pieces of subscriber equipment installed in the line path When a PON system optical network is constructed by allocating channels to M subscriber devices one by one, the PON system station is used to install the plurality of station devices as equipment in a communication station. A method of installing the device,
At the beginning of constructing the PON optical network, the number of subscribers is small, and one channel is provided for at least one subscriber unit connected to each of the N branch splitters of the M N branch splitters (31 to 38). When it is only necessary to allocate one channel to only (N × M) / (multiple of 2) subscriber devices one by one,
Of the plurality of station devices, only the number of station devices (11) necessary for allocating one channel only to (N × M) / (multiple of 2) subscriber devices are communication stations. As installed in the building,
At least one L-branch splitter (21, 22) for connecting the required number of station devices (11) and all of the M N-branch splitters (31 to 38) via optical fibers. Installed as equipment in the communication station building,
One channel is allocated to each of at least one subscriber unit connected to each of the N branch splitters of the M N branch splitters (31 to 38) from the required number of station devices (11), and the total In (N × M) / (multiple of 2) subscriber devices, one channel is allocated one by one.
Number of subscribers connected to at least one N-branch splitter among the M N-branch splitters (31 to 38) after the PON type optical network is constructed. When the number of station devices (11) alone increases and channels cannot be allocated, the other station devices (12) of the plurality of station devices are installed in the communication station building. As a new installation,
Reduce the number of station devices installed as equipment in the communication station at the beginning of constructing the PON optical network with a small number of subscribers.
The installation method of the apparatus for PON system stations characterized by the above-mentioned. Along with the other station device (12), at least one (L / (multiple of 2)) branching splitter (41, 42) is newly installed as equipment in the communication station,
At least one N-branch splitter and the other station device (12) to which the number of connected subscriber devices is increased are connected to the at least one (L / (multiple of 2)) branch splitter (41). , 42), and assigns one channel at a time from the other station device (12) to N subscriber devices connected to the at least one N-branch splitter.
The installation method of the apparatus for PON system stations of Claim 1 characterized by the above-mentioned. When the other station device (12) is newly installed as a communication station facility, at least one other (L / (multiple of 2)) splitter is newly installed as a communication station facility. From the required number of station devices (11) through the at least one other (L / (multiple of 2)) branching splitter and from the other station devices (12) 3. Channels are assigned to said N * M subscriber units one by one via at least one (L / (multiple of 2)) branch splitter (41, 42). Installation method for PON system station. When the plurality of station devices (12) are all installed as equipment in a communication station, the at least one L branch splitter (21, 22) is connected to the at least one other (L / (2 4. The method of installing a PON system station device according to claim 3, wherein the PON system station device is replaced with a multiple splitter). When the plurality of station devices have overlapping channels, the overlapping channels are not assigned to N subscriber devices respectively connected to the M N branch splitters. The PON system station apparatus installation method according to any one of claims 1 to 4, wherein a channel is assigned to each of the N × M subscriber apparatuses from a plurality of station apparatuses. When one station apparatus (11) out of the required number of station apparatuses includes two optical interfaces having overlapping channels,
At the beginning of constructing the PON optical network,
Two L-branch splitters (21, 22) are installed as equipment in the communication station,
The one station apparatus (11) and one L branch splitter (21) of the two L branch splitters (21, 22) are connected to one of the two optical interfaces. Connected via an optical fiber to which an interface channel is assigned, and another one of the L branch splitters (21, 22) and the one L branch splitter (21, 22). (22) is connected via an optical fiber to which the channel of the other optical interface of the two optical interfaces is assigned.
The installation method of the apparatus for PON system stations in any one of Claims 1 thru | or 5 characterized by the above-mentioned. If the other station device (12) comprises two other optical interfaces having overlapping channels,
When the other station device (12) is newly installed as equipment in the communication station,
Two (L / (multiple of 2)) branch splitters (41, 42) are newly installed as equipment in the communication station,
The other station device (12) and one (L / (multiple of 2)) branch splitter (41) out of the two (L / (multiple of 2)) branch splitters (41, 42) Are connected via an optical fiber to which a channel of one other optical interface of the two other optical interfaces is assigned, and the other station apparatus (12) and the two ( L / (multiple of 2)) branch splitter (41, 42) and the other (L / (multiple of 2)) branch splitter (42) of the two other optical interfaces. Connecting through the optical fiber to which the channel of the other optical interface of the other is assigned,
The installation method of the apparatus for PON system stations of Claim 6 characterized by the above-mentioned.

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