US20060018593A1 - Connection of an add/drop node - Google Patents
Connection of an add/drop node Download PDFInfo
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- US20060018593A1 US20060018593A1 US10/089,112 US8911202A US2006018593A1 US 20060018593 A1 US20060018593 A1 US 20060018593A1 US 8911202 A US8911202 A US 8911202A US 2006018593 A1 US2006018593 A1 US 2006018593A1
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- 239000000835 fiber Substances 0.000 claims abstract description 57
- 239000013307 optical fiber Substances 0.000 claims abstract description 38
- 230000003287 optical effect Effects 0.000 claims abstract description 35
- 238000004804 winding Methods 0.000 claims description 4
- 238000010276 construction Methods 0.000 claims description 3
- 230000001902 propagating effect Effects 0.000 abstract description 8
- 238000010586 diagram Methods 0.000 description 5
- 238000006880 cross-coupling reaction Methods 0.000 description 2
- 230000001681 protective effect Effects 0.000 description 2
- 238000010079 rubber tapping Methods 0.000 description 2
- 238000005452 bending Methods 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 230000000903 blocking effect Effects 0.000 description 1
- 230000008878 coupling Effects 0.000 description 1
- 238000010168 coupling process Methods 0.000 description 1
- 238000005859 coupling reaction Methods 0.000 description 1
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- 230000013011 mating Effects 0.000 description 1
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- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/44—Mechanical structures for providing tensile strength and external protection for fibres, e.g. optical transmission cables
- G02B6/4439—Auxiliary devices
- G02B6/444—Systems or boxes with surplus lengths
- G02B6/4453—Cassettes
- G02B6/4454—Cassettes with splices
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04J—MULTIPLEX COMMUNICATION
- H04J14/00—Optical multiplex systems
- H04J14/02—Wavelength-division multiplex systems
- H04J14/0201—Add-and-drop multiplexing
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04J—MULTIPLEX COMMUNICATION
- H04J14/00—Optical multiplex systems
- H04J14/02—Wavelength-division multiplex systems
- H04J14/0201—Add-and-drop multiplexing
- H04J14/0215—Architecture aspects
- H04J14/0219—Modular or upgradable architectures
Definitions
- the present invention relates to an add/drop node of an optical WDM-network, in particular to the connection of an add/drop node to two paths of the network carrying light in opposite directions, and to a network including such an add/drop node.
- Optical networks using WDM are now proposed to be built more and more.
- WDM Widelength Division Multiplexing
- a plurality of add/drop nodes are connected and simple devices should be provided for connecting the nodes to the network.
- An optical network having add/drop nodes is for example disclosed in U.S. Pat. No. 5,754,545.
- an add/drop node is intended to be connected in an optical WDM-network.
- the network has two parallel fiber paths allowing light of a plurality of wavelength channels to propagate in opposite directions.
- the add/drop node comprises two add/drop modules for each of the channels. All the modules are identically constructed and most of their connections are very similar to each other allowing a simple mounting and connection of the components of the node and also a simple rearrangement for changing wavelength channels and for adding/deleting wavelength channels used in the network.
- Each module comprises an add device for adding light to a first one of the paths and a drop device for deflecting a portion of light from a second one of the paths.
- the add device and the drop device of a module are enclosed by comprises a house, the houses of the modules being placed in a single row, at the sides of each other and for instance mounted in a rack.
- a first fixed connector is attached to the house of a module for connection in the first path and to a an optical fiber which extends freely from the house and has a first free connector at its free end to be attached to the fixed connector of a neighbouring add/drop module for continuing the first path through the considered add/drop module to the neighbouring module.
- a second fixed connector is attached to the house for connection in the second path and to a second optical fiber which extends freely from the house and has a second free connector at its free end to be attached to the fixed second connector of a neighbouring add/drop module for continuing the second path through the considered add/drop module to the neighbouring module,
- each add/drop module has an add device or light combiner for adding light to one of the two optical fiber paths and it has also a drop device for deflecting a portion of light from the other optical fiber path. Furthermore, all the add/drop modules have the same construction.
- the add/drop modules can then be arranged in two sets, so that the add/drop modules of a first set have their add devices connected in one fiber path and their drop devices connected in the other fiber path. Also, the add/drop modules of the second set then have their add devices connected in the other fiber path and their drop devices connected in said one fiber path.
- the add/drop modules are placed at the sides of each other and then inner modules and two end modules are obtained in each set.
- an output of the add device in a first one of the two adjacent add/drop modules can be connected to an input of the add device in a second one of the two adjacent add/drop modules.
- an output of the drop device in a first one of the two adjacent add/drop modules can be connected to an input of the drop device in a second one of the two adjacent add/drop modules.
- its drop device can have an output connected to an input of the add device of one of the two end add/drop modules in the other, second set.
- its drop device can have an output connected to an input of the add device of said one end add/drop module in the first set.
- FIG. 1 is a block diagram of an optical network having a ring architecture and a hub node and four client nodes,
- FIG. 2 is a schematic picture of the connection lines of an add/drop module used in the nodes of the network
- FIG. 3 is a view from the side of the inside of a house of an add/drop module
- FIG. 4 is a front view of a plurality of add/drop modules mounted in a rack
- FIG. 5 is a block diagram schematically showing the connections of add/drop modules of the nodes
- FIG. 6 is a block diagram showing in a somewhat more realistic way the connections of add/drop modules of the nodes.
- FIG. 7 is a perspective view showing the inside of a house of an add/drop module.
- FIG. 1 a block diagram of an optical fiber WDM-network having a ring configuration is shown.
- two optical fiber paths 1 e , 1 w pass in a basically uninterrupted way all around the network, one fiber path 1 e carrying light propagating in the east direction and the other fiber path 1 w carrying light propagating in the west direction.
- the network includes a hub node 2 and in the embodiment shown four client nodes 3 , called Client 1 , 2 , 3 and 4 , the nodes being connected to the two basic fiber paths 1 e , 1 w for adding and dropping light from the fibers.
- the hub node 2 is connected to an electrical client portion 5 .
- Such an electrical client portion 5 comprises an electrooptic converter or optical transmitter 7 converting electrical signals to optical signals and an optoelectric converter or optical receiver 9 for receiving optical signals converting the received signals to electrical signals.
- the electrical client portion 5 is through optical fibers connected to an optical client portion 11 in the hub node 2 .
- the optical client portion 11 has optical connectors for receiving the optical fibers extending from the respective electrical client portion.
- the optical client portion 11 comprises an optical receiver-transmitter combination 13 , 15 for transmission, the receiver 13 of the combination receiving the light signal from the transmitter 7 of the electrical client portion 5 providing its output signal to the transmitter 15 of the pair, which provides a well-defined light signal in the narrow wavelength band used for the respective client.
- the optical transmitter 15 is coupled to an optical connector for providing its output signal on an optical fiber to add/drop modules as will be described hereinafter.
- the optical client portion 11 also comprises an optical receiver-transmitter combination for receiving, the combination comprising two optical receivers 17 e , 17 w connected to receive light from the add/drop modules through optical fibers and optical connectors, one receiver 17 e being used for receiving light propagating in the network, in the appropriate fiber, in an east direction and another receiver 17 w being used for receiving light propagating in the west direction in the ring network.
- the outputs of the two optical receivers 17 e , 17 w are connected to inputs of a combining element or optical multiplexer 19 which combines the received signals to provide them to a transmitter 21 , the output terminal of which is through the respective connector and a fiber length connected to the receiver 9 in the electrical client portion 5 .
- the hub node 2 includes a plurality of add/drop modules 231 , 23 r, one pair of such add/drop modules being provided for each client node 3 in the network.
- one module 231 is adapted to transmit in a left direction from the hub node and to receive from the same left direction.
- the other module 23 r of a pair is adapted to transmit in and to receive from the right direction from the hub node.
- Each add/drop module is connected in the two ring-shaped fiber paths 1 e , 1 w of the network.
- a left add/drop module 231 comprises one add device 251 connected in the fiber ring path 1 w and one drop device 271 connected in the other fiber ring path 1 e .
- the add device 251 is through fiber pieces, a 50/50 splitting coupler 29 (only one is shown in the drawing) and the respective connector connected to the transmitter 15 in the optical client portion 11 for the appropriate client node.
- the drop device 271 is through a fiber and the respective connector connected to the receiver 17 e in the optical client portion 11 for the same client node.
- the right add/drop module 23 r in the pair comprises one add device 25 r connected in the fiber ring path 1 e and one drop device 27 r connected in the other fiber ring path 1 w .
- the add device 25 r is through fiber pieces, the respective splitting coupler 29 and the respective connector connected to the transmitter 15 in the optical client portion 11 for the client node.
- the drop device 27 r is through a fiber and the respective connector connected to the receiver 17 w in the optical client portion 11 for the client node.
- the add devices 251 , 25 r contain some coupling or combining element and if required a notch filter blocking light of the wavelength band or channel for which the add/drop module is designed.
- the optional filter will then stop only light of said wavelength band propagating in the respective fiber ring path 1 w , 1 e before light of the same wavelength band is added in the combining element.
- the drop devices 271 , 27 r contain in the same way some splitting and filtering element for tapping off only light of the wavelength band or channel for which the add/drop module is designed.
- add/drop nodes 231 , 23 r have the same basic design and functions and can thus all be given the same physical shape as will be discussed hereinafter.
- the two fiber ring paths 1 e, 1 w are connected to the hub node 2 on a left side of the hub node and on a right side of the node.
- a monitor module 311 , 31 r can be arranged which is thus connected in the two ring paths.
- a monitor module 311 , 31 r comprises an add coupler 331 , 33 r for adding e.g. some control signal and a tap 351 , 35 r for tapping off some small portion of the incoming light power, e.g. 1%.
- the schematic diagram of FIG. 2 illustrates the functions of an add/drop module 231 , 23 r .
- the module comprises a house indicated at 41 .
- Light from one 1 e of two ring paths of the network enters the module at a connector 43 attached to a fiber piece 45 extending loosely outside the house 41 .
- the fiber piece 45 has a thick protective sleeve and is inside the house at 47 welded to an end of an optical fiber 49 having a standard thin protective sleeve.
- the optical fiber piece 49 is at its opposite end connected to one of the two inputs of the add device 251 , 25 r.
- the output of the add device is connected to a fiber piece 51 , which in turn is connected to a connector 53 attached to the house 41 .
- the connector 53 should be connected in the same ring path 1 e as the input connector 43 .
- the other input of the add device is through a fiber piece 55 connected a connector 57 attached to the house 41 .
- the connector 43 thus receives light from the ring path 1 e to make it continue to the fiber 45 , through the weld 47 , the fiber piece 49 , the add device 251 , 25 r , the fiber piece 51 to the connector 53 .
- the output connector 53 lets the light continue along the ring path 1 e .
- Light from an optical client portion 11 enters the module at the connector 57 , continues through the fiber 55 to the add device 251 , 25 r , in which the light is added to that propagating along the ring path 1 e.
- a connector 63 is to be connected to the other ring path and is attached to an end of a well protected fiber piece 65 extending partly outside the house 41 , the other end being connected through a weld 67 to a standard fiber piece 69 .
- This fiber piece is in turn connected to one of the two outputs of the drop device 271 , 27 r .
- the input of the drop device is connected to fiber piece 71 which receives light from a connector 73 attached to the house 41 .
- the connector 73 should be connected in the respective ring path 1 w .
- the other output of the drop device 271 , 27 r is connected to an end of a fiber piece 75 which has its other end connected to a connector 77 attached to the house 41 .
- This connector is through a fiber attached to a respective receiver 17 w ( 17 e ) in the optical client portion 11 .
- Light from the ring path 1 w enters the module at the connector 73 , continues through the fiber 71 , the drop device 271 , 27 r, the fiber 69 , the weld 67 , the thick fiber 65 to the loose connector 63 , which in turn is connected in the respective ring path 1 w of the network.
- Some light of a specific wavelength band is tapped off in the drop device 271 , 27 r and continues through the fiber 75 to the connector 77 and therefrom to the respective optical client portion 11 .
- the physical layout of the interior of an add/drop module house 41 is shown in FIG. 3 .
- the module house 41 comprises a substantially flat portion from which various walls stand out.
- the walls all have the same height and connect to a basically flat lid, not shown, which is mounted over the house 41 .
- the walls form two circular winding cores 81 having a sufficiently large diameter, e.g. about 50 mm, allowing that fibers can be wound around them and not being subjected to too small bending radii (too large curvatures).
- the two winding cores 81 are placed at some distance of each other allowing that fibers can pass therebetween.
- the fiber pieces used can be allowed to have some extra length allowing them to be comfortably handled and to again be spliced to the devices in the case of fiber breaks or bad splices and also, the direction of the fiber pieces at the places where they are connected to the devices can be selected to be the proper one not using too small bends, by placing the fibers for instance in a configuration similar to the figure eight around the two cores 81 .
- Inside the walls forming the winding cores through-holes 83 may be arranged for an easy handling of the module house.
- the add devices 251 , 25 r and the drop devices 271 , 27 r can be attached between outstanding walls 85 at the top of the house.
- the attaching devices are provided for attaching the house to a rack, the attaching devices comprising a notch 87 at the rear side and a snap device 89 at the front side.
- a channel 91 is formed at the front top side of the house 41 to allow fibers connecting the module to the associated optical client portion to be held therein.
- FIG. 4 is a front view of the add/drop modules 231 , 23 r and the monitor modules 311 , 31 r mounted in a rack, the loosely extending fiber pieces 45 , 65 not being visible in this figure.
- FIG. 4 By comparing FIG. 4 to FIG. 1 it is seen that the connection of all left add/drop modules 231 is as indicated in FIG. 3 , the extending fiber pieces 45 being inserted in the mating connectors 53 , 73 in the adjacent module at the left side of the respective module.
- This connection is illustrated in the schematic view of FIG. 6 , see also FIG. 5 .
- FIG. 5 the same basic connection as in FIG. 1 is illustrated, where, in the right modules 23 r the add devices and the drop devices have changed places with each other.
- Such a cross connection can be made by connecting the loose fiber pieces 101 having optical connectors at each end in a cross configuration or a particular cross connecting module can be used.
- a module has the same exterior design as the other modules but has inside just the optical fibers connected cross-wise.
- FIG. 4 a multitude of add/drop modules 231 , 23 r are illustrated. However, only a portion of the add/drop modules may be active ones, constructed as described above. At the side of the active modules dummy modules are inserted having the same exterior layout but without the connectors and the loosely extending fibers. The dummy modules are used for just filling up the space between the active modules and the monitor modules.
- the two monitor modules 311 , 31 r both have the same exterior connectors and interior devices as each other but have not the same interior connection lines. The necessary connections appear clearly from FIG. 1 .
- the client nodes 3 in the network have the same basic design as the hub node 2 but are designed to receive and transmit in only one wavelength band.
- the same kind of add/drop modules as described above can for example be used.
- the client nodes can receive and transmit in more than one wavelength band. Then the client nodes can have the same structure as the hub node 2 .
Abstract
An add/drop node of an optical WDN-network which has two fiber paths for light of a plurality of channels propagating in opposite directions comprises two add/drop modules (231, 23 r) for each of the channels. All the modules are identically constructed. Each module comprises an add device (251, 25 r) for adding light to one of the paths and a drop device (27 r , 271) for deflecting a portion of light from a second one of the paths. A module comprises a house (41) enclosing the add device and the drop device. A first fixed connector (53, 73) is attached to the house for connection in the first path and to a an optical fiber (45, 65) which extends freely from the house and has a first free connector (43, 63) at its free end to be attached to the fixed connector of a neighbouring add/drop module for continuing the first path through the considered add/drop module to the neighbouring module. In the same way a second fixed connector is attached to the house for connection in the second path and to a second optical fiber which extends freely from the house and has a second free connector at its free end to be attached to the fixed second connector of a neighbouring add/drop module for continuing the second path through the considered add/drop module to the neighbouring module.
Description
- The present invention relates to an add/drop node of an optical WDM-network, in particular to the connection of an add/drop node to two paths of the network carrying light in opposite directions, and to a network including such an add/drop node.
- Optical networks using WDM (Wavelength Division Multiplexing) are now proposed to be built more and more. In such networks a plurality of add/drop nodes are connected and simple devices should be provided for connecting the nodes to the network. For example, when an existing node is expanded to be capable of receiving and transmitting in another wavelength band the manual work required therefor should be minimized. An optical network having add/drop nodes is for example disclosed in U.S. Pat. No. 5,754,545.
- It is an object of the invention to provide an add/drop node for an optical WDM-network having a simple way of connecting the node to circulating fiber paths of the network.
- It is another object of the invention to provide an optical WDM-network having an add/drop node built to allow a simple way of connecting the node to parallel fiber paths of the network.
- Thus generally, an add/drop node is intended to be connected in an optical WDM-network. The network has two parallel fiber paths allowing light of a plurality of wavelength channels to propagate in opposite directions. The add/drop node comprises two add/drop modules for each of the channels. All the modules are identically constructed and most of their connections are very similar to each other allowing a simple mounting and connection of the components of the node and also a simple rearrangement for changing wavelength channels and for adding/deleting wavelength channels used in the network. Each module comprises an add device for adding light to a first one of the paths and a drop device for deflecting a portion of light from a second one of the paths. The add device and the drop device of a module are enclosed by comprises a house, the houses of the modules being placed in a single row, at the sides of each other and for instance mounted in a rack. A first fixed connector is attached to the house of a module for connection in the first path and to a an optical fiber which extends freely from the house and has a first free connector at its free end to be attached to the fixed connector of a neighbouring add/drop module for continuing the first path through the considered add/drop module to the neighbouring module. In the same way a second fixed connector is attached to the house for connection in the second path and to a second optical fiber which extends freely from the house and has a second free connector at its free end to be attached to the fixed second connector of a neighbouring add/drop module for continuing the second path through the considered add/drop module to the neighbouring module,
- More particularly, in the add/drop node two add/drop modules are provided for each of the channels of light propagating in the network. Each add/drop module has an add device or light combiner for adding light to one of the two optical fiber paths and it has also a drop device for deflecting a portion of light from the other optical fiber path. Furthermore, all the add/drop modules have the same construction. The add/drop modules can then be arranged in two sets, so that the add/drop modules of a first set have their add devices connected in one fiber path and their drop devices connected in the other fiber path. Also, the add/drop modules of the second set then have their add devices connected in the other fiber path and their drop devices connected in said one fiber path.
- In at least each of the two sets the add/drop modules are placed at the sides of each other and then inner modules and two end modules are obtained in each set. For two adjacent or neighbouring add/drop modules of a set an output of the add device in a first one of the two adjacent add/drop modules can be connected to an input of the add device in a second one of the two adjacent add/drop modules. In the same way, for two adjacent add/drop modules an output of the drop device in a first one of the two adjacent add/drop modules can be connected to an input of the drop device in a second one of the two adjacent add/drop modules. For one of the end add/drop modules comprised in a first set its drop device can have an output connected to an input of the add device of one of the two end add/drop modules in the other, second set. Similarly, for said one end add/drop module of the second set its drop device can have an output connected to an input of the add device of said one end add/drop module in the first set.
- The invention will now be described by way of a non-limiting embodiment with reference to the accompanying drawings, in which
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FIG. 1 is a block diagram of an optical network having a ring architecture and a hub node and four client nodes, -
FIG. 2 is a schematic picture of the connection lines of an add/drop module used in the nodes of the network, -
FIG. 3 is a view from the side of the inside of a house of an add/drop module, -
FIG. 4 is a front view of a plurality of add/drop modules mounted in a rack, -
FIG. 5 is a block diagram schematically showing the connections of add/drop modules of the nodes, -
FIG. 6 is a block diagram showing in a somewhat more realistic way the connections of add/drop modules of the nodes, and -
FIG. 7 is a perspective view showing the inside of a house of an add/drop module. - In
FIG. 1 a block diagram of an optical fiber WDM-network having a ring configuration is shown. Thus twooptical fiber paths fiber path 1 e carrying light propagating in the east direction and theother fiber path 1 w carrying light propagating in the west direction. - The network includes a
hub node 2 and in the embodiment shown fourclient nodes 3, calledClient basic fiber paths hub node 2 can receive and transmit information in all channels, i.e. on all wavelengths λn, n=1, 2, . . . For eachclient node 3, thehub node 2 is connected to anelectrical client portion 5. Such anelectrical client portion 5 comprises an electrooptic converter or optical transmitter 7 converting electrical signals to optical signals and an optoelectric converter oroptical receiver 9 for receiving optical signals converting the received signals to electrical signals. Theelectrical client portion 5 is through optical fibers connected to anoptical client portion 11 in thehub node 2. Theoptical client portion 11 has optical connectors for receiving the optical fibers extending from the respective electrical client portion. - The
optical client portion 11 comprises an optical receiver-transmitter combination 13, 15 for transmission, the receiver 13 of the combination receiving the light signal from the transmitter 7 of theelectrical client portion 5 providing its output signal to thetransmitter 15 of the pair, which provides a well-defined light signal in the narrow wavelength band used for the respective client. Theoptical transmitter 15 is coupled to an optical connector for providing its output signal on an optical fiber to add/drop modules as will be described hereinafter. - The
optical client portion 11 also comprises an optical receiver-transmitter combination for receiving, the combination comprising twooptical receivers receiver 17 e being used for receiving light propagating in the network, in the appropriate fiber, in an east direction and anotherreceiver 17 w being used for receiving light propagating in the west direction in the ring network. The outputs of the twooptical receivers optical multiplexer 19 which combines the received signals to provide them to a transmitter 21, the output terminal of which is through the respective connector and a fiber length connected to thereceiver 9 in theelectrical client portion 5. - Furthermore, the
hub node 2 includes a plurality of add/drop modules client node 3 in the network. In such a pair onemodule 231 is adapted to transmit in a left direction from the hub node and to receive from the same left direction. Theother module 23 r of a pair is adapted to transmit in and to receive from the right direction from the hub node. Each add/drop module is connected in the two ring-shaped fiber paths drop module 231 comprises one add device 251 connected in thefiber ring path 1 w and onedrop device 271 connected in the otherfiber ring path 1 e. The add device 251 is through fiber pieces, a 50/50 splitting coupler 29 (only one is shown in the drawing) and the respective connector connected to thetransmitter 15 in theoptical client portion 11 for the appropriate client node. Thedrop device 271 is through a fiber and the respective connector connected to thereceiver 17 e in theoptical client portion 11 for the same client node. - In the same way, the right add/
drop module 23 r in the pair comprises one adddevice 25 r connected in thefiber ring path 1 e and one drop device 27 r connected in the otherfiber ring path 1 w. The adddevice 25 r is through fiber pieces, therespective splitting coupler 29 and the respective connector connected to thetransmitter 15 in theoptical client portion 11 for the client node. The drop device 27 r is through a fiber and the respective connector connected to thereceiver 17 w in theoptical client portion 11 for the client node. - The
add devices 251, 25 r contain some coupling or combining element and if required a notch filter blocking light of the wavelength band or channel for which the add/drop module is designed. The optional filter will then stop only light of said wavelength band propagating in the respectivefiber ring path drop devices 271, 27 r contain in the same way some splitting and filtering element for tapping off only light of the wavelength band or channel for which the add/drop module is designed. - It appears that all add/
drop nodes - The two
fiber ring paths hub node 2 on a left side of the hub node and on a right side of the node. At each such side amonitor module monitor module add coupler tap 351, 35 r for tapping off some small portion of the incoming light power, e.g. 1%. - The schematic diagram of
FIG. 2 illustrates the functions of an add/drop module connector 43 attached to afiber piece 45 extending loosely outside thehouse 41. Thefiber piece 45 has a thick protective sleeve and is inside the house at 47 welded to an end of an optical fiber 49 having a standard thin protective sleeve. The optical fiber piece 49 is at its opposite end connected to one of the two inputs of theadd device 251, 25 r. The output of the add device is connected to afiber piece 51, which in turn is connected to aconnector 53 attached to thehouse 41. Theconnector 53 should be connected in thesame ring path 1 e as theinput connector 43. The other input of the add device is through afiber piece 55 connected aconnector 57 attached to thehouse 41. Theconnector 43 thus receives light from thering path 1 e to make it continue to thefiber 45, through theweld 47, the fiber piece 49, theadd device 251, 25 r, thefiber piece 51 to theconnector 53. Theoutput connector 53 lets the light continue along thering path 1 e. Light from anoptical client portion 11 enters the module at theconnector 57, continues through thefiber 55 to theadd device 251, 25 r, in which the light is added to that propagating along thering path 1 e. - Furthermore, in the
module other ring path 1 w of the network but in which instead of theadd device 25 r, 251 thedrop device 271, 27 r is connected. Thus aconnector 63 is to be connected to the other ring path and is attached to an end of a well protectedfiber piece 65 extending partly outside thehouse 41, the other end being connected through aweld 67 to a standard fiber piece 69. This fiber piece is in turn connected to one of the two outputs of thedrop device 271, 27 r. The input of the drop device is connected to fiber piece 71 which receives light from aconnector 73 attached to thehouse 41. Theconnector 73 should be connected in therespective ring path 1 w. The other output of thedrop device 271, 27 r is connected to an end of afiber piece 75 which has its other end connected to a connector 77 attached to thehouse 41. This connector is through a fiber attached to arespective receiver 17 w (17 e) in theoptical client portion 11. Light from thering path 1 w enters the module at theconnector 73, continues through the fiber 71, thedrop device 271, 27 r, the fiber 69, theweld 67, thethick fiber 65 to theloose connector 63, which in turn is connected in therespective ring path 1 w of the network. Some light of a specific wavelength band is tapped off in thedrop device 271, 27 r and continues through thefiber 75 to the connector 77 and therefrom to the respectiveoptical client portion 11. - The physical layout of the interior of an add/
drop module house 41 is shown inFIG. 3 . Themodule house 41 comprises a substantially flat portion from which various walls stand out. The walls all have the same height and connect to a basically flat lid, not shown, which is mounted over thehouse 41. The walls form two circular windingcores 81 having a sufficiently large diameter, e.g. about 50 mm, allowing that fibers can be wound around them and not being subjected to too small bending radii (too large curvatures). The two windingcores 81 are placed at some distance of each other allowing that fibers can pass therebetween. By arranging two such cores the fiber pieces used can be allowed to have some extra length allowing them to be comfortably handled and to again be spliced to the devices in the case of fiber breaks or bad splices and also, the direction of the fiber pieces at the places where they are connected to the devices can be selected to be the proper one not using too small bends, by placing the fibers for instance in a configuration similar to the figure eight around the twocores 81. Inside the walls forming the winding cores through-holes 83 may be arranged for an easy handling of the module house. The adddevices 251, 25 r and thedrop devices 271, 27 r can be attached between outstanding walls 85 at the top of the house. - At the lower edge of the
house 41 devices are provided for attaching the house to a rack, the attaching devices comprising anotch 87 at the rear side and asnap device 89 at the front side. Achannel 91 is formed at the front top side of thehouse 41 to allow fibers connecting the module to the associated optical client portion to be held therein. -
FIG. 4 is a front view of the add/drop modules monitor modules fiber pieces FIG. 4 toFIG. 1 it is seen that the connection of all left add/drop modules 231 is as indicated inFIG. 3 , the extendingfiber pieces 45 being inserted in themating connectors FIG. 6 , see alsoFIG. 5 . Thus, inFIG. 5 the same basic connection as inFIG. 1 is illustrated, where, in theright modules 23 r the add devices and the drop devices have changed places with each other. Then a cross coupling must be made between the group ofleft modules 231 and the group ofright modules 23 r and between the right group and theright monitor module 31 r as compared to the straight schematic connection of modules shown inFIG. 1 . The same connection of the modules is illustrated inFIG. 6 in which the connections between the add/drop modules using loosely extending fiber pieces is shown. From this figure it appears clearly that all add/drop modules loose fiber pieces 101 having optical connectors at each end in a cross configuration or a particular cross connecting module can be used. Such a module has the same exterior design as the other modules but has inside just the optical fibers connected cross-wise. InFIG. 4 a multitude of add/drop modules - The two
monitor modules FIG. 1 . - The
client nodes 3 in the network have the same basic design as thehub node 2 but are designed to receive and transmit in only one wavelength band. The same kind of add/drop modules as described above can for example be used. - In other network ring architectures the client nodes can receive and transmit in more than one wavelength band. Then the client nodes can have the same structure as the
hub node 2.
Claims (35)
1. (canceled)
2. An add/drop node to be connected in an optical WDM-network, the network including two optical fiber paths for letting light of a plurality of channels propagate in opposite directions in the network, characterized by two add/drop modules for each of the channels, each add/drop module comprising an add device for adding light to a first one of the two optical fiber paths and a drop device for deflecting a portion of light from a second one of the two optical fiber paths different from the first one and all add/drop modules having the same construction, and in that the add/drop modules are arranged in two sets, the add/drop modules of a first one of the two sets having their add devices connected in the first one of the two optical fiber paths and their drop devices connected in the second one of the two optical fiber paths and the add/drop modules of a second one of the two sets different from the first one having their add devices connected in the second one of the two optical fiber paths and their drop devices connected in the first one of the two optical fiber paths.
3. An add/drop node according to claim 2 , characterized in that in each of the two sets the add/drop modules are placed at the sides of each other, and that for two adjacent add/drop modules an output of the add device in a first one of the two adjacent add/drop modules is connected to an input of the add device in a second one of the two adjacent add/drop modules.
4. An add/drop node according to claim 2 , characterized in that in each of the two sets the add/drop modules are placed at the sides of each other, and that for two adjacent add/drop modules an output of the drop device in a first one of the two adjacent add/drop modules is connected to an input of the drop device in a second one of the two adjacent add/drop modules.
5. An add/drop node according to claim 2 , characterized in that in each of the two sets the add/drop modules are placed at the sides of each other to form inner add/drop modules and two end add/drop modules in each set, the end add/drop modules having an add/drop module of the set on only one side, and that for one of the two end add/drop modules of a first one of the two sets its drop device has an output connected to an input of the add device of one of the two end add/drop modules in a second one of the two sets and that for said one of the two end add/drop modules of the second one of the two sets its drop device has an output connected to an input of the add device of said one of the two end add/drop modules in the first one of the two sets.
6. An add/drop node according to claim 2 , characterized in that each add/drop module comprises a housing enclosing the add device and the drop device of the add/drop module, a first fixed connector attached to the housing for connection in the first one of the two optical fiber paths and a first optical fiber extending freely from the housing and having a first free connector at its free end to be attached to the fixed connector of a neighboring add/drop module for continuing the first path through the considered add/drop module to the neighboring module, and a second fixed connector attached to the housing for connection in the second one of the two optical fiber paths and a second optical fiber extending freely from the housing and having a second free connector at its free end to be attached to the fixed second connector of a neighboring add/drop module for continuing the second path through the considered add/drop module to the neighboring module.
7. An add/drop node according to claim 6 , characterized in that the house includes two winding cores around which excessive fiber lengths connecting devices and connectors of the add/drop module can be wound.
8. (canceled)
9. An add/drop node according to claim 3 , characterized in that in each of the two sets the add/drop modules are placed at the sides of each other to form inner add/drop modules and two end add/drop modules in each set, the end add/drop modules having an add/drop module of the set on only one side, and that for one of the two end add/drop modules of a first one of the two sets its drop device has an output connected to an input of the add device of one of the two end add/drop modules in a second one of the two sets and that for said one of the two end add/drop modules of the second one of the two sets its drop device has an output connected to an input of the add device of said one of the two end add/drop modules in the first one of the two sets.
10. An add/drop node according to claim 4 , characterized in that in each of the two sets the add/drop modules are placed at the sides of each other to form inner add/drop modules and two end add/drop modules in each set, the end add/drop modules having an add/drop module of the set on only one side, and that for one of the two end add/drop modules of a first one of the two sets its drop device has an output connected to an input of the add device of one of the two end add/drop modules in a second one of the two sets and that for said one of the two end add/drop modules of the second one of the two sets its drop device has an output connected to an input of the add device of said one of the two end add/drop modules in the first one of the two sets.
11. (canceled)
12. An add/drop node according to claim 3 , characterized in that each add/drop module comprises a housing enclosing the add device and the drop device of the add/drop module, a first fixed connector attached to the housing for connection in the first one of the two optical fiber paths and a first optical fiber extending freely from the housing and having a first free connector at its free end to be attached to the fixed connector of a neighboring add/drop module for continuing the first path through the considered add/drop module to the neighboring module, and a second fixed connector attached to the housing for connection in the second one of the two optical fiber paths and a second optical fiber extending freely from the housing and having a second free connector at its free end to be attached to the fixed second connector of a neighboring add/drop module for continuing the second path through the considered add/drop module to the neighboring module.
13. An add/drop node according to claim 4 , characterized in that each add/drop module comprises a housing enclosing the add device and the drop device of the add/drop module, a first fixed connector attached to the housing for connection in the first one of the two optical fiber paths and a first optical fiber extending freely from the housing and having a first free connector at its free end to be attached to the fixed connector of a neighboring add/drop module for containing the first path through the considered add/drop module to the neighboring module, and a second fixed connector attached to the housing for connection in the second one of the two optical fiber paths and a second optical fiber extending freely from the housing and having a second free connector at its free end to be attached to the fixed second connector of a neighboring add/drop module for continuing the second path through the considered add/drop module to the neighboring module.
14. An add/drop node according to claim 5 , characterized in that each add/drop module comprises a housing enclosing the add device and the drop device of the add/drop module, a first fixed connector attached to the housing for connection in the first one of the two optical fiber paths and a first optical fiber extending freely from the housing and having a first free connector at its free end to be attached to the fixed connector of a neighboring add/drop module for continuing the first path through the considered add/drop module to the neighboring module, and a second fixed connector attached to the housing for connection in the second one of the two optical fiber paths and a second optical fiber extending freely from the housing and having a second free connector at its free end to be attached to the fixed second connector of a neighboring add/drop module for continuing the second path through the considered add/drop module to the neighboring module.
15. (canceled)
16. (canceled)
17. (canceled)
18. (canceled)
19. (canceled)
20. (canceled)
21. (canceled)
22. (canceled)
23. (canceled)
24. (canceled)
25. (canceled)
26. (canceled)
27. (canceled)
28. (canceled)
29. (canceled)
30. (canceled)
31. (canceled)
32. (canceled)
33. (canceled)
34. (canceled)
35. (canceled)
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
SE9903521A SE9903521L (en) | 1999-09-27 | 1999-09-27 | Connection of an ADD / DROP NOD |
SE9903521-4 | 1999-09-27 | ||
PCT/SE2000/001877 WO2001024432A1 (en) | 1999-09-27 | 2000-09-27 | Connection of an add/drop node |
Publications (2)
Publication Number | Publication Date |
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US20060018593A1 true US20060018593A1 (en) | 2006-01-26 |
US6999654B1 US6999654B1 (en) | 2006-02-14 |
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Application Number | Title | Priority Date | Filing Date |
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US09/631,102 Expired - Lifetime US6684005B1 (en) | 1999-09-27 | 2000-08-01 | Connection of an add/drop node |
US10/089,112 Expired - Lifetime US6999654B1 (en) | 1999-09-27 | 2000-09-27 | Connection of on an add/drop node |
Family Applications Before (1)
Application Number | Title | Priority Date | Filing Date |
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US09/631,102 Expired - Lifetime US6684005B1 (en) | 1999-09-27 | 2000-08-01 | Connection of an add/drop node |
Country Status (10)
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US (2) | US6684005B1 (en) |
EP (1) | EP1216532B1 (en) |
JP (1) | JP4636400B2 (en) |
CN (1) | CN100356719C (en) |
AT (1) | ATE377302T1 (en) |
AU (1) | AU7820900A (en) |
CA (1) | CA2385587C (en) |
DE (1) | DE60036954T2 (en) |
SE (1) | SE9903521L (en) |
WO (1) | WO2001024432A1 (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20040067007A1 (en) * | 2001-01-31 | 2004-04-08 | Carl-Johan Arbeus | Method and system for transmission in an optical network |
Families Citing this family (18)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
SE9903521L (en) * | 1999-09-27 | 2001-03-28 | Queyton Systems Ab | Connection of an ADD / DROP NOD |
JP4520763B2 (en) * | 2004-03-29 | 2010-08-11 | 富士通株式会社 | Relay transmission equipment |
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US8559818B2 (en) | 2007-10-26 | 2013-10-15 | Adc Telecommunications, Inc. | Methods and systems for delivery of multiple passive optical network services |
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US9075217B2 (en) | 2010-04-30 | 2015-07-07 | Corning Cable Systems Llc | Apparatuses and related components and methods for expanding capacity of fiber optic housings |
CN103649805B (en) | 2011-06-30 | 2017-03-15 | 康宁光电通信有限责任公司 | Fiber plant assembly of shell using non-U-width size and associated method |
US8953924B2 (en) | 2011-09-02 | 2015-02-10 | Corning Cable Systems Llc | Removable strain relief brackets for securing fiber optic cables and/or optical fibers to fiber optic equipment, and related assemblies and methods |
IT201600126393A1 (en) * | 2016-12-14 | 2018-06-14 | Btg Italia S P A | MODULE FOR THE MANAGEMENT OF OPTICAL FIBERS |
Citations (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5680235A (en) * | 1995-04-13 | 1997-10-21 | Telefonaktiebolaget Lm Ericsson | Optical multichannel system |
US5754545A (en) * | 1995-02-23 | 1998-05-19 | Fujitsu Limited | Add-drop multiplexer with enhancement of accessibility to signals in different hierarchical levels and flexibility in various services and circuit setting operations |
US5774606A (en) * | 1996-05-17 | 1998-06-30 | Lucent Technologies, Inc. | Optical fiber transmission system with a passive optical router |
US5778132A (en) * | 1997-01-16 | 1998-07-07 | Ciena Corporation | Modular optical amplifier and cassette system |
US5832156A (en) * | 1996-10-31 | 1998-11-03 | Lucent Technologies Inc. | Article comprising an optical waveguide tap |
US5953141A (en) * | 1996-10-03 | 1999-09-14 | International Business Machines Corporation | Dynamic optical add-drop multiplexers and wavelength-routing networks with improved survivability and minimized spectral filtering |
US5982791A (en) * | 1998-01-14 | 1999-11-09 | Hewlett-Packard Company | Wavelength tracking in adjustable optical systems |
US6160616A (en) * | 1997-11-11 | 2000-12-12 | Kabushiki Kaisha Topcon | Laser system |
US6163392A (en) * | 1997-05-23 | 2000-12-19 | Ciena Corporation | Distributed intelligence wavelength division multiplexed network |
US6169616B1 (en) * | 1998-06-04 | 2001-01-02 | Avanex Corporation | Optical and programmable fiber optic wavelength add/drop system |
US6333799B1 (en) * | 1997-01-07 | 2001-12-25 | Tellium, Inc. | Hybrid wavelength-interchanging cross-connect |
US6631018B1 (en) * | 1997-08-27 | 2003-10-07 | Nortel Networks Limited | WDM optical network with passive pass-through at each node |
US6684005B1 (en) * | 1999-09-27 | 2004-01-27 | Cisco Systems (Sweden) Aktiebolag | Connection of an add/drop node |
Family Cites Families (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH0444439A (en) * | 1990-06-12 | 1992-02-14 | Toshiba Corp | Optical communication system |
JPH0943450A (en) * | 1995-07-27 | 1997-02-14 | Furukawa Electric Co Ltd:The | Optical branching unit |
JP3055603B2 (en) * | 1996-07-19 | 2000-06-26 | 日本電気株式会社 | Optical network |
JPH1068828A (en) * | 1996-08-29 | 1998-03-10 | Mitsubishi Gas Chem Co Inc | Optical waveguide module having trunk line waveguide and transmission system |
JP3068018B2 (en) * | 1996-12-04 | 2000-07-24 | 日本電気株式会社 | Optical wavelength division multiplex ring system |
JP3216886B2 (en) | 1996-12-11 | 2001-10-09 | インターナシヨナル・ビジネス・マシーンズ・コーポレーション | Digital cross-connect and add / drop multiplexing device |
JPH10186142A (en) * | 1996-12-20 | 1998-07-14 | Fujikura Ltd | Optical fiber excess length storing structure, optical wiring method and working jig |
JP3448448B2 (en) * | 1997-02-14 | 2003-09-22 | 株式会社フジクラ | Optical wiring rack |
US6657952B1 (en) | 1997-11-28 | 2003-12-02 | Nec Corporation | Ring network for sharing protection resource by working communication paths |
SE520876C2 (en) | 1998-06-10 | 2003-09-09 | Ericsson Telefon Ab L M | ADD / Drpo node for an optical WDM network that has traffic only between neighboring nodes |
-
1999
- 1999-09-27 SE SE9903521A patent/SE9903521L/en not_active Application Discontinuation
-
2000
- 2000-08-01 US US09/631,102 patent/US6684005B1/en not_active Expired - Lifetime
- 2000-09-27 JP JP2001527493A patent/JP4636400B2/en not_active Expired - Lifetime
- 2000-09-27 AT AT00968268T patent/ATE377302T1/en not_active IP Right Cessation
- 2000-09-27 US US10/089,112 patent/US6999654B1/en not_active Expired - Lifetime
- 2000-09-27 CA CA002385587A patent/CA2385587C/en not_active Expired - Fee Related
- 2000-09-27 DE DE60036954T patent/DE60036954T2/en not_active Expired - Lifetime
- 2000-09-27 EP EP00968268A patent/EP1216532B1/en not_active Expired - Lifetime
- 2000-09-27 WO PCT/SE2000/001877 patent/WO2001024432A1/en active IP Right Grant
- 2000-09-27 CN CNB008133646A patent/CN100356719C/en not_active Expired - Fee Related
- 2000-09-27 AU AU78209/00A patent/AU7820900A/en not_active Abandoned
Patent Citations (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5754545A (en) * | 1995-02-23 | 1998-05-19 | Fujitsu Limited | Add-drop multiplexer with enhancement of accessibility to signals in different hierarchical levels and flexibility in various services and circuit setting operations |
US5680235A (en) * | 1995-04-13 | 1997-10-21 | Telefonaktiebolaget Lm Ericsson | Optical multichannel system |
US5774606A (en) * | 1996-05-17 | 1998-06-30 | Lucent Technologies, Inc. | Optical fiber transmission system with a passive optical router |
US5953141A (en) * | 1996-10-03 | 1999-09-14 | International Business Machines Corporation | Dynamic optical add-drop multiplexers and wavelength-routing networks with improved survivability and minimized spectral filtering |
US5832156A (en) * | 1996-10-31 | 1998-11-03 | Lucent Technologies Inc. | Article comprising an optical waveguide tap |
US6333799B1 (en) * | 1997-01-07 | 2001-12-25 | Tellium, Inc. | Hybrid wavelength-interchanging cross-connect |
US5778132A (en) * | 1997-01-16 | 1998-07-07 | Ciena Corporation | Modular optical amplifier and cassette system |
US6163392A (en) * | 1997-05-23 | 2000-12-19 | Ciena Corporation | Distributed intelligence wavelength division multiplexed network |
US6631018B1 (en) * | 1997-08-27 | 2003-10-07 | Nortel Networks Limited | WDM optical network with passive pass-through at each node |
US6160616A (en) * | 1997-11-11 | 2000-12-12 | Kabushiki Kaisha Topcon | Laser system |
US5982791A (en) * | 1998-01-14 | 1999-11-09 | Hewlett-Packard Company | Wavelength tracking in adjustable optical systems |
US6169616B1 (en) * | 1998-06-04 | 2001-01-02 | Avanex Corporation | Optical and programmable fiber optic wavelength add/drop system |
US6684005B1 (en) * | 1999-09-27 | 2004-01-27 | Cisco Systems (Sweden) Aktiebolag | Connection of an add/drop node |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20040067007A1 (en) * | 2001-01-31 | 2004-04-08 | Carl-Johan Arbeus | Method and system for transmission in an optical network |
Also Published As
Publication number | Publication date |
---|---|
ATE377302T1 (en) | 2007-11-15 |
DE60036954T2 (en) | 2008-08-14 |
WO2001024432A1 (en) | 2001-04-05 |
US6999654B1 (en) | 2006-02-14 |
CA2385587C (en) | 2008-07-29 |
CN100356719C (en) | 2007-12-19 |
AU7820900A (en) | 2001-04-30 |
EP1216532B1 (en) | 2007-10-31 |
JP2003510961A (en) | 2003-03-18 |
CN1378729A (en) | 2002-11-06 |
DE60036954D1 (en) | 2007-12-13 |
SE9903521D0 (en) | 1999-09-27 |
US6684005B1 (en) | 2004-01-27 |
CA2385587A1 (en) | 2001-04-05 |
EP1216532A1 (en) | 2002-06-26 |
SE9903521L (en) | 2001-03-28 |
JP4636400B2 (en) | 2011-02-23 |
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