WO1998015861A1 - Procede et appareil pour combiner des lignes de signaux optiques a insertion/extraction en provenance de plusieurs unites de derivation - Google Patents

Procede et appareil pour combiner des lignes de signaux optiques a insertion/extraction en provenance de plusieurs unites de derivation Download PDF

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Publication number
WO1998015861A1
WO1998015861A1 PCT/US1997/015738 US9715738W WO9815861A1 WO 1998015861 A1 WO1998015861 A1 WO 1998015861A1 US 9715738 W US9715738 W US 9715738W WO 9815861 A1 WO9815861 A1 WO 9815861A1
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WO
WIPO (PCT)
Prior art keywords
port
passing
optical signal
trunk
add
Prior art date
Application number
PCT/US1997/015738
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English (en)
Inventor
Bo Pedersen
Original Assignee
Tyco Submarine Systems Ltd.
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Tyco Submarine Systems Ltd. filed Critical Tyco Submarine Systems Ltd.
Priority to CA002267779A priority Critical patent/CA2267779A1/fr
Priority to AU47998/97A priority patent/AU4799897A/en
Priority to JP51750698A priority patent/JP4105233B2/ja
Priority to EP97910697A priority patent/EP1012646A1/fr
Publication of WO1998015861A1 publication Critical patent/WO1998015861A1/fr

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Classifications

    • 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
    • G02B6/24—Coupling light guides
    • G02B6/26—Optical coupling means
    • G02B6/28—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals
    • G02B6/293—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means
    • G02B6/29304—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means operating by diffraction, e.g. grating
    • G02B6/29316—Light guides comprising a diffractive element, e.g. grating in or on the light guide such that diffracted light is confined in the light guide
    • G02B6/29317—Light guides of the optical fibre type
    • G02B6/29319—With a cascade of diffractive elements or of diffraction operations
    • G02B6/2932—With a cascade of diffractive elements or of diffraction operations comprising a directional router, e.g. directional coupler, circulator
    • 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
    • G02B6/24—Coupling light guides
    • G02B6/26—Optical coupling means
    • G02B6/28—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals
    • G02B6/293—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means
    • G02B6/29379—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means characterised by the function or use of the complete device
    • G02B6/2938—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means characterised by the function or use of the complete device for multiplexing or demultiplexing, i.e. combining or separating wavelengths, e.g. 1xN, NxM
    • G02B6/29382—Optical coupling means having data bus means, i.e. plural waveguides interconnected and providing an inherently bidirectional system by mixing and splitting signals with wavelength selective means characterised by the function or use of the complete device for multiplexing or demultiplexing, i.e. combining or separating wavelengths, e.g. 1xN, NxM including at least adding or dropping a signal, i.e. passing the majority of signals
    • G02B6/29383—Adding and dropping
    • 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
    • H04J14/0202—Arrangements therefor
    • H04J14/0206—Express channels arrangements
    • 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
    • H04J14/0202—Arrangements therefor
    • H04J14/0213—Groups of channels or wave bands arrangements
    • 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
    • H04J14/0217—Multi-degree architectures, e.g. having a connection degree greater than two
    • 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 invention relates to optical signal processing in a lightwave communications system. More particularly, the invention relates to a method and apparatus for combining the add/drop lines for multiple add/drop multiplexers (ADMs) into a single pair of add/drop lines.
  • ADMs add/drop multiplexers
  • Lightwave communications systems applied in the field of telecommunications can be broadly classified into two categories. These two categories are referred to as long-haul and short-haul systems, depending on whether the optical signal is transmitted over relatively long or short distances compared with typical intercity distances (approximately 50 to 100 kilometers) . Long-haul communications systems require high-capacity trunk lines and can transmit information over several thousands of kilometers using optical amplifiers.
  • optical add-drop multiplexer referred to as an ADM or branching unit
  • An ADM is known as a key device for use in splitting and inserting wavelength-multiplexed optical signals.
  • FIG. 10 illustrates one example of a conventional ADM.
  • ADM 20 comprises demultiplexer 22, multiplexer 24, and N lines of optical fibers 14a, 14b . . . I4n.
  • multiplexed input optical signals consisting of wavelengths lambda ( ⁇ ) 1, ⁇ 2 . . . ⁇ n are separated into optical signals of N wavelengths from which desired optical signals, for example, ⁇ i and ⁇ j, are outputted ("dropped").
  • the remaining optical signals are transmitted through the optical fibers 14a, 14b . . . 14n.
  • External ⁇ i and ⁇ j are inputted into a multiplexer ("added") along with those signals transmitted through optical fibers 14a,
  • each trunk line has its own ADM.
  • each ADM requires at least one fiber pair to add and drop certain wavelengths of information. Therefore, the number of fiber pairs increases in proportion to the number of ADMs used in the system. This not only increases the amount of fiber used for the system, but also ADM controllers and related optical components. Furthermore, it is impossible to transfer traffic between trunks without additional optical components since each ADM uses its own fiber pair.
  • This invention provides a system for arranging the multiple ADMs such that each ADM utilizes the same fiber pair to add and drop certain wavelengths of wavelength- multiplexed optical signals carried on high-capacity fiber trunks.
  • the invention also provides an ADM apparatus capable of passing certain wavelengths of optical signals from the add line to the drop line of the ADM.
  • the invention provides a system for arranging multiple ADMs such that signals from one fiber trunk line can be rerouted to another fiber trunk line using the same fiber pair.
  • the invention uses a single fiber pair for carrying branch traffic from a plurality of branching units attached to a plurality of trunk fibers.
  • the invention comprises a plurality of optical fiber trunks for carrying trunk traffic, and a plurality of branching units, each attached to one of the fiber trunks, and each having an add and drop port.
  • a single fiber pair connects the branching units for carrying branch traffic between the branching units.
  • Each branching unit is capable of passing branch traffic from an add port to a drop port.
  • FIG. 1 is a block diagram of a lightwave communications system in which an embodiment of the present invention may be deployed.
  • FIG. 2 is a schematic drawing of an ADM for use with an embodiment of the present invention.
  • FIG. 3(a) is a schematic diagram of one embodiment of a passing device for an embodiment of the present invention.
  • FIG. 3(b) is a schematic diagram of a second embodiment of a passing device for an embodiment of the present invention.
  • FIG. 3(c) is a schematic diagram of a third embodiment of a passing device for an embodiment of the present invention.
  • FIG. 4 is a block diagram in accordance with an embodiment of the present invention.
  • FIG. 5 is a block diagram in accordance with a second embodiment of the present invention.
  • FIG. 6 is a block diagram in accordance with a third embodiment of the present invention.
  • FIG. 7 is a block diagram in accordance with a fourth embodiment of the present invention.
  • FIG. 8 is a block diagram in accordance with a fifth embodiment of the present invention.
  • FIG. 9 is a block diagram in accordance with a sixth embodiment of the present invention.
  • FIG. 10 is a schematic drawing of a conventional ADM.
  • FIG. 1 illustrates a block diagram of a lightwave communications system in which an embodiment of the present invention may be deployed.
  • FIG. 1 illustrates a high-capacity wavelength division multiplexing (WDM) lightwave communications system.
  • WDM wavelength division multiplexing
  • WDM is used to transmit two channels in different transmission windows of the optical fiber.
  • an existing lightwave system operating at ⁇ N can be upgraded in capacity by adding another channel of ⁇ P.
  • a typical WDM system operates in the 1550 nanometer (nm) window, for example, ⁇ 1 to ⁇ N in the range from 1530 nm to 1565 nm.
  • Optical communications transmitters 200, 214 and 216 transmit optical communications channels at wavelength ⁇ 1, ⁇ 2 . . . ⁇ N, respectively.
  • Multiplexer 210 multiplexes these signals together to form multiplexed signal 202.
  • Muliplexed signal 202 is launched into optical fiber 204 for transmission to the receiving end. Since optical fiber 204 is a high- capacity trunk, signal 202 is also referred to as "trunk traffic.”
  • multiplexed signal 202 passes through ADM 206.
  • ADM 206 places multiplexed signal 234 back onto optical fiber 204.
  • demultiplexer 212 demultiplexes and routes ⁇ 1, ⁇ 2 . . . ⁇ N to receivers 208, 218 . . . 220, respectively.
  • FIG. 2 provides a more detailed schematic of ADM 206.
  • ADM 206 includes trunk in 204, trunk out 236, branch in 340 and branch out 360.
  • This embodiment of the invention uses a single fiber pair 350 comprised of branch in 340 and branch out 360.
  • FIG. 2 shows added fiber pair 385 comprised of branch in 39 and branch out 38.
  • a single fiber pair can be used to add or drop a plurality of wavelengths from multiplexed signal 202. For purposes of this embodiment of the invention, however, only fiber pair 350 will be discussed.
  • Demultiplexer 300 demultiplexes multiplexed signal 202 as it passes through ADM 206 from trunk in 204.
  • Wavelengths ⁇ 1, ⁇ 2 . . . ⁇ n are routed onto optic fiber 304, 306 . . . 308, respectively.
  • ADM 206 places wavelength ⁇ i on optic fiber 360 and thereby branches ⁇ i to a desired destination.
  • the optical information signal of wavelength ⁇ i is referred to as "branch traffic," since ADM 206 branches it from trunk in 204 to optic fiber 360.
  • ADM 206 replaces ⁇ i by taking ⁇ i from branch in 340.
  • Multiplexer 302 multiplexes ⁇ i along with ⁇ l, ⁇ 2 . . . ⁇ n forming multiplexed signal 234, which is launched onto fiber optic 236 toward the receiving end.
  • multiplexed signal 234 is different from multiplexed signal 202 since the optical information signal of wavelength ⁇ i has been replaced with a different optical information signal of wavelength ⁇ i.
  • multiplexed signal 202 and 234 may include the same signal wavelengths, they do not necessarily carry the same information.
  • ADM 206 contains passing device 466, which permits certain signals coming from branch in 340 to pass through ADM 206 to continue transmission over branch out 360. Examples of different configurations for passing device 466 are shown in FIGs. 3(a), 3(b) and 3(c).
  • FIG. 3(a) is a diagram of passing device 466. Passing device 466 passes all wavelengths but the wavelength (s) being added or dropped (e.g. , ⁇ i) .
  • FIG. 3(a) shows trunk in 496, trunk out 498, branch in 492, branch out 494, and circulators 476 and 474, all of which are connected through fiber grating 472.
  • fiber grating 472 is a Bragg grating.
  • Other examples for fiber grating 472 can include diffraction gratings, interference induced gratings, Fabry-Perot etalon, gergonian router, or any other mechanism for selectively passing wavelengths.
  • Fiber grating 472 deflects the bragg wavelength and passes all other wavelengths. In this manner, the desired wavelength can be added to the multiplexed signal placed on trunk out 498, while those signals with destinations at other ADMs pass onto branch out 494.
  • FIG. 3(b) illustrates an alternative embodiment for passing desired signals from the add line to the drop line.
  • FIG. 3(b) shows passing device 468 which performs the same function as passing device 466, except it does so using couplers rather than circulators.
  • An opto- isolator 484 is added to coupler 482 used for branch in 500, to prevent signals from entering branch in 500.
  • FIG. 3(c) illustrates a third embodiment for a passing device. As with passing devices 466 and 468, passing device 470 performs the identical function. Passing device 470, however, uses coupler 488 and circulator 486 to perform this function. Notice that placement of circulator 486 on the branch in side of the ADM removes the need for an additional opto-isolator, thereby reducing the overall number of components.
  • the signals which are permitted to pass through ADM 206 are all the signals except for the signal which is added and dropped from the multiplexed signals.
  • all wavelengths traveling from branch in 340 will pass through ADM 206 to branch out 360 except for wavelength ⁇ i.
  • FIG. 4 is a block diagram in accordance with a first embodiment of the present invention.
  • FIG. 4 shows system 41 having input trunk 1, trunk 2 . . . trunk N, referred to as 42, 44 and 46, respectively.
  • System 41 also has output trunk 1, trunk 2 . . . trunk N, referred to as 48, 50 and 52, respectively.
  • system 41 uses fiber pair referred to as branch add input 54 and branch drop output 56.
  • ADMs 58, 60 and 62 are all attached to branch add input 54 and branch drop output 56, as well as to trunk pairs 42 and 48, 44 and 50, and 46 and 52, respectively. More particularly, the ADMs are configured such that the branch out line of one ADM becomes the branch in line of an adjacent ADM.
  • the topology of system 41 is such that optic fiber 47 serves as both the branch out of ADM 62 and the branch in of ADM 60.
  • optic fiber 45 serves as both the branch out of ADM 60 and branch in of ADM 58.
  • Optic fiber 43 serves as the branch out of ADM 58.
  • optic fiber 43 directs the dropped signal to any desired location. It is, however, possible for optic fiber 43 to serve as the branch in for ADM 62. This configuration is discussed in reference to FIG. 8.
  • system 41 has a single fiber pair to add and drop signals from multiple trunk lines using multiple ADMs. Since passing device 466 only permits those signals of wavelengths different from the added signal and dropped signal, there exists only four possibilities for processing signals through ADM 206, summarized in the following table:
  • passing device 466 of ADM 58, 60 and 62 passes all wavelengths except the Bragg wavelength (or branching wavelength), ADM 58, 60 and 62 is transparent with respect to these wavelengths.
  • an incoming multiplexed signal be defined as containing signals of wavelength ⁇ 1 to ⁇ 5 carried on input trunk lines 42, 44 and 46. Further, assume that ADM 62 branches out wavelengths ⁇ 2 and ⁇ 3, ADM 60 branches out ⁇ 5, and ADM 58 branches out ⁇ 1 and ⁇ 4.
  • ⁇ 1 to ⁇ 5 are dropped from trunk in 42, 44 and 46 and branched to a desired destination using only a single fiber pair.
  • ADM 62 branches out ⁇ 2 and ⁇ 3 onto optic fiber 47, which carries these signals into ADM 60. Since the passing device (not shown) of ADM 60 reflects only wavelength ⁇ 5, wavelengths ⁇ 2 and ⁇ 3 pass through ADM 60 onto fiber optic 45 to ADM 58.
  • ADM 60 also branches out ⁇ 5 from trunk in 44 onto fiber optic 45 as well. Thus, ⁇ 2, ⁇ 3 and ⁇ 5 are transmitted to ADM 58.
  • ADM 58 Since the passing device (not shown) of ADM 58 only reflects wavelengths ⁇ 1 and ⁇ 4, wavelengths ⁇ 2, ⁇ 3 and ⁇ 5 pass through ADM 58 onto fiber optic 43. At the same time, ⁇ 1 and ⁇ 4 from trunk in 42 are placed onto fiber optic 43 by ADM 58. Similarly, ⁇ 1 to ⁇ 5 can be added to trunk out 48, 50 and 52. If we assume ⁇ 1 to ⁇ 5 are transmitted into ADM 62 from fiber optic 54, the passing device of ADM 62 reflects ⁇ 2 and ⁇ 3 which are multiplexed together with wavelengths ⁇ 1, ⁇ 4 and ⁇ 5 from trunk in 46, and sent over trunk out 52.
  • the passing device of ADM 60 reflects ⁇ 5 which is multiplexed together with ⁇ 1 to ⁇ 4 from trunk in 44, and sent over trunk out 50.
  • the passing device of ADM 58 reflects ⁇ 1 and ⁇ 4 which are multiplexed together with ⁇ 2 , ⁇ 3 and ⁇ 5 from trunk in 42, and sent over trunk out 48. It is worthy of note that a system designer must carefully configure a system so that two ADMs do not branch out the same wavelength, unless necessary to reach a specific design goal, e.g. , to route signals from one trunk to another trunk as described in more detail with reference to FIG. 9.
  • FIG. 5 is a block diagram in accordance with a second embodiment of the present invention.
  • This second embodiment includes a multi-trunk, ulti-ADM system similar to the system shown in FIG. 4.
  • the system in FIG. 4 has all the incoming trunk lines carrying signals in the same direction.
  • alternating trunk in lines 72, 76 and 80 are carrying signals in a direction opposite of trunk in lines 70, 74 and 78.
  • This embodiment operates similarly to the first embodiment discussed with reference to FIG. 4.
  • FIG. 6 is a block diagram in accordance with a third embodiment of the present invention.
  • This third embodiment includes a multi-trunk, multi-ADM system similar to the system shown in FIG. 5.
  • the third embodiment uses two fiber pairs to add and drop signals from ADMs placed on alternating trunk lines.
  • fibers 146 and 148 carry add/drop signals to/from ADMs 134, 136 and 138, which connect to trunk lines 112, 116 and 120 operating in one direction
  • fibers 150 and 152 carry add/drop signals to/from ADMs 140, 142 and 144, which connect to trunk lines 122, 126 and 130 operating in the opposite direction.
  • the third embodiment operates similarly to the first embodiment discussed with reference to FIG. 4.
  • FIG. 7 is a block diagram in accordance with a fourth embodiment of the present invention.
  • This fourth embodiment includes a multi-trunk, multi-ADM system similar to the system shown in FIG. 5.
  • the fourth embodiment uses a single fiber pair to add and drop signals from ADMs placed on duplicate pairs of trunk lines, with each pair of trunk lines alternating in direction.
  • trunk in 154, 158 and 162 carry information in one direction
  • trunk in 156, 160 and 164 carry information in the opposite direction.
  • the fourth embodiment operates similarly to the first embodiment discussed with reference to FIG. 4.
  • FIG. 8 is a block diagram in accordance with a fifth embodiment of the present invention.
  • the fifth embodiment is identical in topology as the embodiment discussed in reference to FIG. 4, with the exception that fiber optic 61 is connected to the add port of ADM 438. In this manner, signals from one trunk line can be routed to another trunk line.
  • An example similar to the previous example made with reference to FIG. 4 is useful in demonstrating the operation of the fifth embodiment shown in FIG. 8.
  • an incoming multiplexed signal be defined as containing signals of wavelength ⁇ 1 to ⁇ 5 on input trunk lines 42, 44 and 46. Assume in this example, however, that ADM 62 branches out wavelength ⁇ 5, ADM 60 branches out ⁇ 2 , and ADM 58 branches out ⁇ 5.
  • ADM 62 branches out ⁇ 5 onto optic fiber 61, which carries this signal into ADM 60. Since the passing device (not shown) of ADM 60 reflects only wavelength ⁇ 2, wavelength ⁇ 5 passes through ADM 60 onto fiber optic 61 to ADM 58. ADM 60 also branches out ⁇ 2 from trunk in 44 onto fiber optic 61 as well. Thus, ⁇ 2 and ⁇ 5 are transmitted to ADM 58. Since the passing device (not shown) of ADM 58 is configured to reflect wavelength ⁇ 5, wavelength ⁇ 5 from fiber optic 61 is routed towards trunk out 48 where it is multiplexed together with ⁇ 1 to ⁇ 4 from trunk in 42. Wavelength ⁇ 2 passes through ADM 58 onto fiber optic 61. At the same time, ⁇ 5 from trunk in 42 is placed onto fiber optic 61 by ADM 58.
  • ADM 62 As ⁇ 2 to ⁇ 5 are carried into ADM 62 from fiber optic 61, the passing device of ADM 62 reflects ⁇ 5 which is multiplexed together with wavelengths ⁇ 1 to ⁇ 4 from trunk in 46. The multiplexed signal is sent over trunk out 52.
  • the above example shows the fifth embodiment routing ⁇ 5 from trunk in 46 to trunk out 48. Further, it shows the fifth embodiment routing ⁇ 5 from trunk in 42 to trunk out 52.
  • FIG. 9 is a block diagram in accordance with a sixth embodiment of the present invention.
  • the sixth embodiment is similar in design to that of the fifth embodiment, with the following exception.
  • the sixth embodiment of the invention accomplishes this by adding an ADM for each wavelength to be routed.
  • FIG. 9 shows system 455 having input trunk 1 to trunk 4, referred to as 440, 442, 444 and 446, respectively.
  • System 455 also has output trunk 1 to trunk 4, referred to as 448, 450, 452 and 454, respectively.
  • System 455 uses fiber optic 464 to connect ADMs 456, 458, 460 and 462.
  • ADMs 456, 458, 460 and 462 are connected to trunk pairs 440 and 448, 442 and 450, 444 and 452, and 446 and 454, respectively.
  • Trunk in 440, 442, 444 and 446 each carry ⁇ 1 to ⁇ 5.
  • ADM 456 branches ⁇ 1 and ⁇ 2;
  • ADM 460 branches ⁇ 1;
  • ADM 462 branches ⁇ 2.
  • ADM 456 branches ⁇ 1 and ⁇ 2, which are passed by fiber optic 464 into ADM 462.
  • ADM 462 branches out ⁇ 2, and passes ⁇ 1 from fiber optic 464 and ⁇ 2 from trunk in 446 to ADM 460.
  • ADM 460 branches out ⁇ 1, and passes through ⁇ 2 from fiber optic 464 and ⁇ 1 from trunk in 444 to ADM 458, which passes both to ADM 456.
  • ADM 456 branches out ⁇ 1 and ⁇ 2.
  • system 455 routes ⁇ 1 and ⁇ 2 from trunk in 444 and 446, respectively, to trunk out 448.
  • System 455 also routes ⁇ 1 from trunk in 440 to trunk out 452, and ⁇ 2 from trunk in 440 to trunk out 454.
  • the trunk lines may carry a combination of WDM and single-channel lines.
  • the trunk lines were illustrated with five channels, any number of channels is possible and each trunk line can have a different number of channels.

Abstract

Cette invention se rapporte à un procédé et à un appareil de traitement de signaux optiques, qui servent à combiner les lignes d'insertion/extraction de plusieurs multiplexeurs d'insertion/extraction (ADM) (58, 60,62) en une seule paire de lignes d'insertion/extraction (54, 56), ce procédé et cet appareil utilisant plusieurs lignes réseau à fibres optiques (42, 44, 46, 48, 50, 52) pour assurer le traffic interurbain, plusieurs unités de dérivation (58, 60, 62) reliées chacune à l'une des lignes réseau à fibres optiques et comportant chacune un port d'insertion et d'extraction, un réseau de fibres (472) prévu dans chaque unité de dérivation et servant à transférer le traffic interurbain du port d'insertion au port d'extraction de chacune des unités de dérivation, et une seule paire de fibres connectant les unités de dérivation pour assurer le traffic de dérivation entre les unités de dérivation.
PCT/US1997/015738 1996-10-10 1997-10-08 Procede et appareil pour combiner des lignes de signaux optiques a insertion/extraction en provenance de plusieurs unites de derivation WO1998015861A1 (fr)

Priority Applications (4)

Application Number Priority Date Filing Date Title
CA002267779A CA2267779A1 (fr) 1996-10-10 1997-10-08 Procede et appareil pour combiner des lignes de signaux optiques a insertion/extraction en provenance de plusieurs unites de derivation
AU47998/97A AU4799897A (en) 1996-10-10 1997-10-08 Method and apparatus for combining add/drop optical signal lines from a plural ity of branching units
JP51750698A JP4105233B2 (ja) 1996-10-10 1997-10-08 複数の分岐ユニットからの挿入／抜き出し光信号ラインを結合する方法及び装置
EP97910697A EP1012646A1 (fr) 1996-10-10 1997-10-08 Procede et appareil pour combiner des lignes de signaux optiques a insertion/extraction en provenance de plusieurs unites de derivation

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US72859196A 1996-10-10 1996-10-10
US08/728,591 1996-10-10

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WO1998015861A1 true WO1998015861A1 (fr) 1998-04-16

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EP (1) EP1012646A1 (fr)
JP (1) JP4105233B2 (fr)
AU (1) AU4799897A (fr)
CA (1) CA2267779A1 (fr)
TW (1) TW357504B (fr)
WO (1) WO1998015861A1 (fr)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2352105A (en) * 1999-07-15 2001-01-17 Marconi Comm Ltd Optical system with interconnected add/drop multiplexers
WO2001007947A1 (fr) * 1999-07-26 2001-02-01 Apa Optics, Inc. Multiplexeur et demultiplexeur pour liaisons de communication par fibres optiques mono-mode

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5311501A (en) * 1991-03-15 1994-05-10 Fujitsu Limited Routing system for linear add-drop multiplexer
US5479082A (en) * 1993-08-10 1995-12-26 Cselt-Centro Studi E Laboratorti Telecommunicazioni S.P.A. Device for extraction and re-insertion of an optical carrier in optical communications networks
US5555118A (en) * 1993-06-04 1996-09-10 Ciena Corporation Method for removing and inserting optical carriers in a WDM optical communication system
US5566014A (en) * 1994-12-28 1996-10-15 At&T Corp. Tunable add/drop optical filter providing arbitrary channel arrangements
US5574807A (en) * 1993-10-29 1996-11-12 Rutgers University Coupler used to fabricate add-drop devices, dispersion compensators, amplifiers, oscillators, superluminescent devices, and communications systems

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
SE502619C2 (sv) * 1994-10-11 1995-11-27 Ericsson Telefon Ab L M Optisk NxN-våglängdskorskopplare
SE503514C2 (sv) * 1995-02-06 1996-07-01 Ericsson Telefon Ab L M Anordning och förfarande för att koppla en eller flera våglängdskanaler till och från en optisk fiber
EP0842574B1 (fr) * 1995-08-04 2002-04-03 Alcatel Multiplexeur a insertion-extraction
JPH09270770A (ja) * 1996-04-02 1997-10-14 Kokusai Denshin Denwa Co Ltd <Kdd> 光アドドロップ装置
JPH1032562A (ja) * 1996-07-16 1998-02-03 Fujitsu Ltd 光アッド／ドロップ回路
JPH11514758A (ja) * 1996-08-29 1999-12-14 コーニング インコーポレイテッド スイッチ可能な光信号加入／除去装置
JP3333093B2 (ja) * 1996-08-30 2002-10-07 ケイディーディーアイ株式会社 波長交換装置

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5311501A (en) * 1991-03-15 1994-05-10 Fujitsu Limited Routing system for linear add-drop multiplexer
US5555118A (en) * 1993-06-04 1996-09-10 Ciena Corporation Method for removing and inserting optical carriers in a WDM optical communication system
US5479082A (en) * 1993-08-10 1995-12-26 Cselt-Centro Studi E Laboratorti Telecommunicazioni S.P.A. Device for extraction and re-insertion of an optical carrier in optical communications networks
US5574807A (en) * 1993-10-29 1996-11-12 Rutgers University Coupler used to fabricate add-drop devices, dispersion compensators, amplifiers, oscillators, superluminescent devices, and communications systems
US5566014A (en) * 1994-12-28 1996-10-15 At&T Corp. Tunable add/drop optical filter providing arbitrary channel arrangements

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6647209B1 (en) 1998-02-13 2003-11-11 Apa Optics, Inc. Multiplexer and demultiplexer for single mode optical fiber communication links
GB2352105A (en) * 1999-07-15 2001-01-17 Marconi Comm Ltd Optical system with interconnected add/drop multiplexers
EP1069719A2 (fr) * 1999-07-15 2001-01-17 Marconi Communications Limited Système optique
GB2352105B (en) * 1999-07-15 2001-09-26 Marconi Comm Ltd Optical system
US6519061B1 (en) 1999-07-15 2003-02-11 Marconi Communications Limited Traffic switching between different wavelength multiplexed channels in optical communications systems
EP1069719A3 (fr) * 1999-07-15 2005-10-12 Marconi UK Intellectual Property Ltd Système optique
WO2001007947A1 (fr) * 1999-07-26 2001-02-01 Apa Optics, Inc. Multiplexeur et demultiplexeur pour liaisons de communication par fibres optiques mono-mode

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JP2001505728A (ja) 2001-04-24
AU4799897A (en) 1998-05-05
JP4105233B2 (ja) 2008-06-25
TW357504B (en) 1999-05-01
CA2267779A1 (fr) 1998-04-16
EP1012646A1 (fr) 2000-06-28

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