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2009 - Optical Cable Network Deployment for Multi-Dwelling-Unit


									                 Optical Cable Network Deployment for Multi-Dwelling-Unit
                            Kotaro Ueda, Yukihiro Yokomachi*, Hiroshi Miyano*,
                                Jonathan Bertucci** and George A. Mackie**
 Sumiden High Precision Co., LTD.               *Sumitomo Electric Industries, LTD. **Sumitomo Electric Lightwave Corp.
 *1, Taya-cho Sakae-ku Yokohama                 **1, Taya-cho Sakae-ku Yokohama        78 Alexander Drive Research
          244-8588 Japan                                 244-8588 Japan                Triangle Park, NC 27709 USA
                                       TEL:+81-(0)45-853-7310 ,

Abstract                                                                                                            Vertical
                                                                                                                    Raceway 4F
This paper describes a new optical distribution system using
“Free-Branch Cable” in which each fiber can be individually
accessed at any point along the span of the bundle of optical cords.
We propose the application that the Free-Branch Cables are
deployed on the floor or on the outside wall surface of Multi-                                                    Drop Cable
                                                                            Tight cabling space
Dwelling Unit (MDU) building and each fiber is accessed to each                   Raceway                             ONT
unit in response to the demand of FTTH service.                                                                               2F
As an actual example of the deployment, one of our solutions was                        Optical
applied to the existing building and clarified the convenience and                      Cords
the efficiency of the Free-Branch Cable for MDU building.                                                             ONT
Keywords: Optical cabling network; Multi-Dwelling Unit;
FTTH; Ribbon cord; Free-Branch Cable; Transition device; SC;                  OSP
Mid span access                                                               cable

1. Introduction
                                                                                  Fig.1 Conventional Optical Solution (1)
In accordance with the spread of high-speed FTTH service, the
demand of an optical distribution for MDU is increasing rapidly.                      Vertical
Figure 1 shows an example of the conventional way to deploy the                       Raceway
                                                                                                                  Drop Cable
optical cables in MDU. The Fiber Distribution Hub (FDH) with
built-in splitter is set to the entrance of building and a drop cable                                                    ONT
is installed from FDH to each unit whenever the demand of FTTH                                                             3F
                                                                                      Multi fiber
is occurred. However, this way leads to the problems of frequent
construction works to wire from FDH to each unit with respect to
each service order and no more space to deploy the additional                                                            ONT
cables inside the raceway in accordance with the increase of                                                               2F
Figure 2 shows another conventional way by which deploy optical
cables in MDU. The multi-fiber cable is installed in the vertical
direction and each individual drop cable is distributed in the
horizontal direction. The multi-fiber cable can be accessed at mid-       OSP
span and spliced to each individual drop cable in the distribution        cable
cabinet installed in every floor. This solution could clear up the
problem of distribution space for vertical raceway. However, this
solution requires the cabinets so that this way leads to another
problem of the construction cost for the installation.                                              Distribution Cabinet
                                                                                                     Uncut fibers
Furthermore, in case of an existing building, especially a small
                                                                                                     Mass Fusion Splice
size of MDU, there is no more space to deploy additional cables in
                                                                                                     Pre-terminated Module
the existing pipe line. Thus, the optical cable network spread of
MDU has fallen behind as compared with that of Single-Family                                          Field Assembly
Unit (SFU).                                                                                           Connector
In this paper, we propose a low-cost optical cabling solution which
is able to save the space for deployment and wire to each unit
within a short time by using the Free-Branch Cable. Although the
deployment is different in each case, the design concept of the                   Fig.2 Conventional Optical Solution (2)
cable is common for any scale of MDU.

International Wire & Cable Symposium                                504                      Proceedings of the 58th IWCS/IICIT
2 Cabling system for Large MDU                                               At the same time when a vertical cable is deployed, this horizontal
                                                                             Free-Branch Cables are set on the floor in a loop. Therefore, when
A large-scale MDU has approximately more than ten to several                 a service order occurs, the construction work can be finished just
dozens of units on every floor. A conventional method has been               by cutting the cord near the dwelling unit and terminating with a
adopted to deploy a drop cable to the ONT of each dwelling unit              field installable connector.
with a vacant space of an existing telephone conduit as an optical
service order occurred.
                                                                                     12-f Ribbon                               Bundle of 2mm cords
However, the deployment was frequently performed because of
                                                                                         Cord                                  (Free Branch Cable)
distributing the optical cable from FDH to every unit whenever a                                                 (10mm)
                                                                                     (5 x 2.5mm)                                      12 of
service order occurred. The cabling space becomes tight and                                              Transition
additional cabling cannot be performed as subscriber is increased.                                                                    2mm cord
The method using the multi-fiber cable for a vertical distribution                                        e
cable (Fig.2) could have been solved the space problem. However, a
cabinet is needed for splicing a vertical cable with a horizontal cable,                                   (250mm)
so that there have been the difficulties in ensuring an installation
space and going up an installation cost.                                                  Fig.4 Cable Configuration for Large MDU
For the purpose of solving these problems, we propose a new
distribution solution used the ribbon cords terminated multi-fiber
                                                                             In case the MDU is not so large, the bundle of ribbon cords
connectors at both ends for a vertical cable and used a bundle of
                                                                             terminated with MPO connectors is no need as shown in Fig.5.
single fiber cords split from the ribbon cords for a horizontal cable
                                                                             The outline of construction is described below.
(Fig.3). Vertical ribbon cords are bundled and preliminarily
divaricated so as to drop into each floor. The connecting point of a         The first step is to set the transition device to the routine floor. The
vertical cord and a horizontal one is terminated with MPO connector          second one is to drop the ribbon cord downstairs and connect into
and protected in a connector sleeve whose size is 140 mm (L) x 25            FDH. The last one is to set to Free-Branch Cable in a loop using a
mm (W) x 18 mm (H). It is so compact that it can break the                   duct on dwelling units. The initial work is done with the three
problems with an installation space.                                         steps.
                                                                             The field worker cuts and drops a cord within his reach at any
              l aceway
              R                           Field                              position near dwelling unit and terminates a field installable
                                             Connector                       connector to connect the ONT of the dwelling unit when service
                                                             ONT             order occurs. This work does not require any cabinet and can help
                                                                             to eliminate the need for the frequent deployment which requires a
         3F                                                     ONT          large amount of time. As a result, the field worker will finish the
                                         Free-Branch Cable                   work in a very short time.

       Bundle of 12f
       Ribbon Cords w/                            MPO connector
       MPO at both ends
                                                                                                   Field Installable
         1F                                                                                          Connector
                                     Connector Case
OS                                   140 mm (L)
c                                    x 25 mm (W)
                                     x 18 mm (H)                                                        ONT

        Fig.3 Cabling Network for Large scale of MDU                                                Device              Bundle
                                                                                                                       of Cords
The horizontal cable has a transition device dividing a ribbon cord
                                                                                                Ribbon Cord
into a bundle of 2mm cords as shown in Fig.4. The ribbon cord is
spliced to the fibers of individual cords inside the transition device
in the factory. The transition device is 30mm OD by 250mm
length and so sufficient compact as to free the limitation of space.
The Free-Branch Cable is a bundle of 2mm cords and each fiber
                                                                                     Fig.5 Cabling Network for middle scale of MDU
can be accessed at any point along the span.

International Wire & Cable Symposium                                   505                           Proceedings of the 58th IWCS/IICIT
3 Cabling system for Small MDU                                               4 Field Trial for small MDU
Most of the MDU are comparatively small scale from a few                     We have conducted a field trial for testing our solution of small
houses to several dozens of houses in total. There have been two             MDU at an existing building. The outline is as follows;
issues: The existing telephone conduit is small, it’s impossible for
additional deploying newly and there is no space to set up the               The cables for a field trial were the same configuration as shown in
cabinet.                                                                     Fig.7. The cables were vertically deployed at ten points in the
                                                                             building as shown in Fig.8. Five ribbon cords ware spliced into a
We propose a new solution applicable to such a small MDU by                  cabinet set in the basement of the building.
distributing the cable on an outer wall surface (Fig.6). The
applicable cable configuration is as shown in Fig.7.                                 Connection of Cable with Cabinet at BF
The Free-Branch Cable bundled with single fiber cords is designed                        Cabinet                            Cabinet
to finish one construction work. The cable sheath material is
applicable to the outdoor environment and the cable has a central
strength member (CSM) to secure on a wall. The cable can be
divided and terminated with connectors preliminary in the factory
because the vertical pitch of each floor is almost common. Once
the Free-Branch Cable is vertically deployed on the outside wall of
the building, the construction work for the service order can be
finished only by pulling the cable into a dwelling unit and
connecting with ONT. This cable makes easier deployment than the
conventional ones in the field. In addition, the connector is secured
to prevent from damage in outdoor environment.                                          Ribbon Drop Cable          Transition Device

The plural ribbon cords are deployed from the buildings to FDH so
as to increase the take rate of splitter involved in FDH and cover                   Connection of Cable with ONT at 1F-6F
plural Multi-Dwelling Units with one FDH. The cable and a bundle
of cords are pre-spliced in the factory.


                      Knee Wall

                 of Cords
                                                         ONT                        Fig.8 Floor Map of the MDU for the Field Trial
                                                                                                                 Protection cap
                                                                                             6m Coil of
                                                                                             3mm cord
                Ribbon Drop Cable            Device                                                              SC connector
               Fig.6. Cable Network for Small MDU

                                                                        Bundle of 3mm cords
                                                                                                                       6m coil of
                                       Transition Device                (Free Blanch Cable)
                                                                                                                       3mm cord
                  Ribbon drop              (φ30mm)
               cable(10.9 x 5mm)

                                                   (250mm)                                                                    CSM
                                                                        3m             3m           SC connector

                                           Fig.7. Cable Configuration for Small MDU

International Wire & Cable Symposium                                506                             Proceedings of the 58th IWCS/IICIT
Figure 9 shows the deployment procedure and photographs. The             along the outer wall horizontally and drag the cable into the
installation works were done by two workers (one worker was on the       exterior FDH in the building. The transition device can be secured
top side and the other was on the ground side). The cable was            on the building wall during this deployment work (Picture 5).
coiled up in 80 centimeters diameter to go up and down the stairs        Thus, the cabinet is unnecessary at the connecting point.
on worker’s shoulder (Picture 1).
The first step was to go up to the top. The second step was to drop
the ribbon cable to the ground from the top of the building (Picture
2). The third step was to secure CSM on the top and ground walls
(Picture 3, Picture 4). The last step was to drop the ribbon cable

                                                (1) A worker                  Knee (3) Knee
                                                      on the top              Wall     Wall


                                                                                        (4)        Window

                                                                                                     6m Coil

                                                                           A worker on
                                                                           the ground
                          Transition                   (5)      Ribbon             to the cabinet
                          Device                                drop               at BF

                                           Fig.9 Cabling network of Field Trial for small MDU

International Wire & Cable Symposium                               507                         Proceedings of the 58th IWCS/IICIT
5 Characteristics and Performance                                                                 6 Conclusions
Table.1 shows the typical characteristics and performance of the                                  We proposed a new solution for the optical cable network
cable on outdoor wall used for this field trial.                                                  deployment for MDU by using the Free-Branch Cable with a
                                                                                                  transition device. The Free-Branch cable is applicable to the
                                                                                                  deployment on the floor and the outside wall surface of any scales
                                    Table1. Characteristics and Performance                       of the building. We made clear the new solution is convenient and
                                                                                                  effective for the FTTH construction.
                                      Item             Characteristics and Performance

                                             Fiber          Equivalent to G.657.B                 7 Authors
                                       Cord diameter                  3mm                         Kotaro Ueda

                                             sheath      PVC(Black) ,UV resistance
                                                                                                  Sumiden High Precision Co., LTD.
                                         Number of                                                1, Taya-cho, Sakae-ku, Yokohama,
                                           cords                                                  244-8588 Japan
                                    Outer diameter                   10mm               

                                        CSM              Dielectric, Flat (5 X 11mm)
                                    Flammability                UL1666 Riser
                                                                                                  Kotaro Ueda received his B.E. degree from Hokkaido University
                                        Temperature    -40 to 70deg C                             in 2002. He joined Sumitomo Electric Industries, LTD. in 2002,

                                                                            <0.06 dB/km           and has been engaged in the development of optical connectors.
                                          Cycling         (GR-20)

                                                                                                  He is now working for Sumiden High Precision Co., LTD..
                                             Water      1m, 24hours
                                                                            No water leak
                                         Penetration      (GR-20)
                                                                                                  Yukihiro Yokomachi
                                           Tensile         1320N              <0.01 dB
                                         Strength of                                              Sumitomo Electric Industries, LTD.
                                            Cable        (GR-409)           No Cracking           1, Taya-cho, Sakae-ku, Yokohama,
                                                                                                  244-8588 Japan

                                          Impact           5.9Nm              < 0.01dB            E-mail:
                                         Resistance      (GR-409)           No Cracking 
                                                                              < 0.01dB
                                         Cable Twist    10cycle, 50N                              Yukihiro Yokomachi received his M.S. degree from Waseda
                                                                            No Cracking
                                                         (GR-409)                                 University in 1989. He joined Sumitomo Electric Industries, LTD.
                                                                                                  in 1989 and has been engaged in the research and development of
                                      Dimension            25mm(D) X 250mm(L)                     optical connector assemblies and the sales engineering of fiber
                                                       Plastic covered with UV resistant          management products for FTTH. He is an assistant general
                                       Material                                                   manager for Fiber Management Products & Systems in the
                                                              heat shrinkable tube
                                                                                                  Lightwave Network Products Division.
                                        Temperature    -40 to 75deg C

                                                                              < 0.10dB
                                          Cycling        (GR-2866)
Transition Device

                                             Water     3m waterhead                               Hiroshi Miyano
                                                                             No damage
                                          resistance     (GR-771)
                                                                                                  Sumitomo Electric Industries, LTD.
                                                           44.5N                                  1, Taya-cho, Sakae-ku, Yokohama,
                                             Tensile                         < 0.01 dB            244-8588 Japan
                                                         (GR-2866)                                E-mail:

                                          Side pull                          < 0.05 dB
                                                        9.8N,100cyc.                              Hiroshi Miyano received his B.E. degree from Tokyo
                                              Flex                            < 0.05dB
                                                         (GR-2866)                                Metropolitan University in 1996. He joined Sumitomo Electric
                                                                                                  Industries, LTD in 1996 and has been engaged in development of
                                                                                                  fiber optic cables since then. He is a senior engineer of
                                                                                                  engineering department in optical fiber and cable division.

International Wire & Cable Symposium                                                        508                         Proceedings of the 58th IWCS/IICIT
Jonathan Bertucci                                                     George A. Mackie

Sumitomo Electric Lightwave Corp.                                     Sumitomo Electric Lightwave Corp.
78 Alexander Drive Research                                           78 Alexander Drive Research
Triangle Park, NC 27709 USA                                           Triangle Park, NC 27709 USA
E-mail:                                                               E-mail:                              

                                                                      George Mackie is the senior product specialist for Sumitomo
Jonathan "Jeb" Bertucci is the product manager – new business         Electric Lightwave (SEL) where his role includes directing
development for Sumitomo Electric Lightwave (SEL), working to         product development for fiber optic MDU applications. Prior to
advance MDU fiber optic technology and passive component              joining SEL eight years ago, George had acquired thirty-one years
application. Prior to his present position, Jeb was a SEL             of experience in the telecommunications industry, with vast
applications engineer for the optical cable and splicer product       expertise in OSP engineering and the development of industry
lines. Jeb is a Mechanical Engineer with an undergraduate degree      standards. He has been active in FTTH deployment for the past
from Worcester Polytechnic Institute in Worcester, MA. He has         twenty years bringing to SEL a valuable mix of knowledge and
fourteen years experience in applications engineering and product     experience.

International Wire & Cable Symposium                            509                         Proceedings of the 58th IWCS/IICIT

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