WO2000057584A1 - Device for channel-specific dispersion compensation of a wavelength multiplex signal - Google Patents

Device for channel-specific dispersion compensation of a wavelength multiplex signal Download PDF

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Publication number
WO2000057584A1
WO2000057584A1 PCT/DE2000/000661 DE0000661W WO0057584A1 WO 2000057584 A1 WO2000057584 A1 WO 2000057584A1 DE 0000661 W DE0000661 W DE 0000661W WO 0057584 A1 WO0057584 A1 WO 0057584A1
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WO
WIPO (PCT)
Prior art keywords
signals
arrangement according
wdm
channel
stλl
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PCT/DE2000/000661
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German (de)
French (fr)
Inventor
Peter Krummrich
Original Assignee
Siemens Aktiengesellschaft
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Filing date
Publication date
Application filed by Siemens Aktiengesellschaft filed Critical Siemens Aktiengesellschaft
Priority to JP2000607360A priority Critical patent/JP2002540676A/en
Priority to AU35507/00A priority patent/AU3550700A/en
Priority to EP00914055A priority patent/EP1161804A1/en
Publication of WO2000057584A1 publication Critical patent/WO2000057584A1/en

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Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04J—MULTIPLEX COMMUNICATION
    • H04J14/00—Optical multiplex systems
    • H04J14/02—Wavelength-division multiplex systems
    • H04J14/0227—Operation, administration, maintenance or provisioning [OAMP] of WDM networks, e.g. media access, routing or wavelength allocation
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B10/00—Transmission systems employing electromagnetic waves other than radio-waves, e.g. infrared, visible or ultraviolet light, or employing corpuscular radiation, e.g. quantum communication
    • H04B10/25—Arrangements specific to fibre transmission
    • H04B10/2507—Arrangements specific to fibre transmission for the reduction or elimination of distortion or dispersion
    • H04B10/2513—Arrangements specific to fibre transmission for the reduction or elimination of distortion or dispersion due to chromatic dispersion
    • H04B10/25133—Arrangements specific to fibre transmission for the reduction or elimination of distortion or dispersion due to chromatic dispersion including a lumped electrical or optical dispersion compensator

Definitions

  • the invention relates to an arrangement for channel-specific dispersion compensation of a wavelength division multiplex signal according to the preamble of patent claim 1.
  • Standard solutions for dispersion compensation of WDM signals are shown in FIG. 1.
  • precompensation is carried out by a dispersion-compensating fiber DCF0 together for all WDM channels.
  • the residual compensation takes place, for example, by means of a dispersion-compensating fiber DCF1, which is sent to the output of the WDM demultiplexer 2 is switched on.
  • a circulator 4 with a dispersion-compensating fiber half length DCFl / 2, at the end of which a reflector R is arranged.
  • the dispersion-compensating fibers have a greater dispersion than the transmission fiber, but with a different sign.
  • only one transmission channel can be exactly compensated with a certain dispersion-compensating fiber, ie the other channels concerned are not optimally compensated.
  • An attempt is being made to design the dispersion-compensating fibers in accordance with the transmission fiber. However, this is usually unsuccessful, since it is not possible to set any course of the dispersion as a function of the wavelength and, on the other hand, the transmission fibers used also have specimen scatter.
  • the dispersion tolerance range of the receivers usually has to be designed so broad that they can also detect signals in inadequately compensated channels without errors. If the residual dispersion values of the individual channels deviate more from each other, this considerably narrows the tolerance range.
  • Another variant also uses a circulator 5, to the middle connection of which a chirped (not uniform) fiber grating 6 is connected.
  • These fiber grids are supplied with certain dispersion values, which can be changed slightly by mechanical tensioning.
  • a major disadvantage of chirped fiber grids is their fluctuations in the phase response. These fluctuations lead to additional signal distortions, which can largely negate the advantages of channel-selective dispersion compensation.
  • the object of the invention is to provide an arrangement for dispersion compensation which enables a channel-specific adaptation with little effort.
  • a dispersion-compensating fiber DCFO through which the WDM signal S ⁇ l-8 passes, is connected to an optical transmission fiber 1.
  • the dispersion-compensating fiber (a broadband chirped fiber grating can also be used) is dimensioned, for example, such that at least most WDM channels or channel signals SK1-SK8 are slightly under-compensated.
  • This precompensated WDM signal ST ⁇ l-8 is fed to a wavelength demultiplexer 2, which works as a filter for the individual channels or channel signals and outputs each of the partially compensated signals ST ⁇ l-ST ⁇ 8 at a separate output.
  • the individual signals are converted into analog or digital electrical signals in converters W1-W8 and each fed to a filter F1-F8. If, in special cases, optimal compensation has already taken place in one of the channels, the filter can be omitted.
  • the filters can be designed as transversal filters or recursive filters. Transversal filters are particularly advantageous because they can also be optimized for systems in operation.
  • a second order transverse filter is generally sufficient for satisfactory compensation.
  • the filter coefficients are optimized based on measurements of the signal quality.
  • the compensated signals SK ⁇ l to SK ⁇ 8 are fed to outputs AI to A8 - possibly via an amplifier in each case - to a sampling stage or other suitable receiving device.

Abstract

First, the wavelength multiplex (WDM) signal (Sμ1-8) is partially compensated in a common dispersion compensator (DCF0). The partially compensated WDM signal is divided into individual partially compensated channel signals (ST1-ST8) in a wavelength demultiplexer (2). These are converted into electrical signals and compensated in filters (F1 to F8).

Description

Beschreibungdescription
Anordnung zur kanalindividuellen Dispersionskompensation eines Wellenlängen-MultiplexsignalsArrangement for channel-specific dispersion compensation of a wavelength division multiplex signal
Die Erfindung betrifft eine Anordnung zur kanalindividuellen Dispersionskompensation eines Wellenlängen-Multiplexsignals nach dem Oberbegriff des Patentanspruchs 1.The invention relates to an arrangement for channel-specific dispersion compensation of a wavelength division multiplex signal according to the preamble of patent claim 1.
In optischen Ubertragungssystemen mit hohen Datenraten ergibt sich bei längeren Übertragungsstrecken häufig die Notwendigkeit, die von der Dispersion der Übertragungsfaser verursachten Verzerrungen des Datensignals zu kompensieren. Beispielsweise wird durch die Dispersion bei einer Datenrate von 10 Gbit/s die Ubertragungslänge bei Standard-Monomoden-Fasern ohne Kompensation nicht wesentlich über eine Übertragungslänge von 100km hinausgehen. In Einkanalsystemen läßt sich die Dispersionskompensation entsprechend der anfallenden Dispersion durchführen. Bei Wellenlängen-Multiplexsystemen (WDM) treten jedoch für die einzelnen Kanalwellenlängen in der Regel unterschiedliche Dispersionswerte auf. Im Idealfall sollte für jeden Kanal eine individuelle Dispersionskompensation durchgeführt werden.In optical transmission systems with high data rates, there is often the need to compensate for the distortion of the data signal caused by the dispersion of the transmission fiber over longer transmission distances. For example, due to the dispersion at a data rate of 10 Gbit / s, the transmission length for standard monomode fibers without compensation will not significantly exceed a transmission length of 100 km. In single-channel systems, dispersion compensation can be carried out in accordance with the resulting dispersion. In wavelength division multiplex systems (WDM), however, different dispersion values generally occur for the individual channel wavelengths. Ideally, individual dispersion compensation should be carried out for each channel.
Standardlösungen zur Dispersionskompensation von WDM-Signalen sind in Figur 1 dargestellt. Zunächst erfolgt eine Vorkompensation durch eine dispersionskompensierende Faser DCF0 gemeinsam für alle WDM-Kanäle. Nach der Aufteilung eines empfangenen WDM-Signals Sλl-8 in einzelne teilkompensierte Ka- näle bzw. Signale STλl-STλ8 durch einen Wellenlängen (WDM) - Demultiplexer 2 erfolgt die Restkompensation beispielsweise durch eine dispersionskompensierende Faser DCF1, die an den Ausgang des WDM-Demultiplexers 2 angeschaltet ist. Eine Variante verwendet einen Zirkulator 4 mit einer dispersionskom- pensierenden Faser halber Länge DCFl/2, an deren Ende ein Reflektor R angeordnet ist. Die dispersionskompensierenden Fasern weisen bei gleicher Länge eine stärkere Dispersion als die Übertragungsfaser auf, jedoch mit anderem Vorzeichen. In der Regel gelingt mit einer bestimmten dispersionskompensierenden Faser nur die Kompensa- tion eines Ubertragungskanals exakt, d.h. die anderen betroffenen Kanäle sind nicht optimal kompensiert. Es wird zwar versucht, die dispersionskompensierenden Fasern entsprechend der Übertragungsfaser auszulegen. Das gelingt jedoch meist nur unzureichend, da sich nicht beliebige Verläufe der Dis- persion in Abhängigkeit von der Wellenlänge einstellen lassen und andererseits auch die verwendeten Übertragungsfasern Exemplarstreuungen aufweisen.Standard solutions for dispersion compensation of WDM signals are shown in FIG. 1. First of all, precompensation is carried out by a dispersion-compensating fiber DCF0 together for all WDM channels. After dividing a received WDM signal Sλl-8 into individual partially compensated channels or signals STλl-STλ8 by a wavelength (WDM) demultiplexer 2, the residual compensation takes place, for example, by means of a dispersion-compensating fiber DCF1, which is sent to the output of the WDM demultiplexer 2 is switched on. One variant uses a circulator 4 with a dispersion-compensating fiber half length DCFl / 2, at the end of which a reflector R is arranged. With the same length, the dispersion-compensating fibers have a greater dispersion than the transmission fiber, but with a different sign. As a rule, only one transmission channel can be exactly compensated with a certain dispersion-compensating fiber, ie the other channels concerned are not optimally compensated. An attempt is being made to design the dispersion-compensating fibers in accordance with the transmission fiber. However, this is usually unsuccessful, since it is not possible to set any course of the dispersion as a function of the wavelength and, on the other hand, the transmission fibers used also have specimen scatter.
In realisierten Systemen muß deshalb der Dispersions-Tole- ranzbereich der Empfänger zumeist so breit ausgelegt werden, daß sie auch Signale in unzureichend kompensierten Kanälen fehlerfrei detektieren können. Wenn die Restdispersionswerte der Einzelkanäle stärker voneinander abweichen, engt dies aber den Toleranzbereich erheblich ein.In realized systems, therefore, the dispersion tolerance range of the receivers usually has to be designed so broad that they can also detect signals in inadequately compensated channels without errors. If the residual dispersion values of the individual channels deviate more from each other, this considerably narrows the tolerance range.
Weiterhin können zusätzliche Signalverzerrungen durch nicht lineare Effekte der Übertragungsfaser den Toleranzbereich einengen. Der Hauptnachteil der vorstehend beschriebenen Möglichkeiten besteht darin, daß sie für realen Einsatz nur schwer praktikabel sind, da eine individuelle Kompensation schwer durchführbar ist.Furthermore, additional signal distortions due to non-linear effects of the transmission fiber can narrow the tolerance range. The main disadvantage of the possibilities described above is that they are difficult to practice for real use because individual compensation is difficult to carry out.
Eine weitere Variante verwendet ebenfalls einen Zirkulator 5, an dessen Mittleren Anschluß jeweils ein gechirptes (nicht gleichmäßiges) Fasergitter 6 angeschlossen ist. Diese Fasergitter werden mit bestimmten Dispersionswerten geliefert, die durch mechanisches Verspannen noch geringfügig geändert werden können. Ein wesentlicher Nachteil der gechirpten Fasergitter besteht in ihren Schwankungen des Phasenganges. Diese Schwankungen führen zu zusätzlichen Signalverzerrungen, welche die Vorteile der kanalselektiven Dispersionskompensation zum großen Teil wieder zunichte machen können. Aufgabe der Erfindung ist es, eine Anordnung zur Dispersionskompensation anzugeben, die eine kanalindividuelle Anpassung mit geringem Aufwand ermöglicht.Another variant also uses a circulator 5, to the middle connection of which a chirped (not uniform) fiber grating 6 is connected. These fiber grids are supplied with certain dispersion values, which can be changed slightly by mechanical tensioning. A major disadvantage of chirped fiber grids is their fluctuations in the phase response. These fluctuations lead to additional signal distortions, which can largely negate the advantages of channel-selective dispersion compensation. The object of the invention is to provide an arrangement for dispersion compensation which enables a channel-specific adaptation with little effort.
Ein Ausführungsbeispiel der Erfindung wird anhand Figur 2 näher erläutert.An embodiment of the invention is explained in more detail with reference to Figure 2.
An eine optische Übertragungsfaser 1 ist eine dispersionskom- pensierende Faser DCFO angeschaltet, die vom WDM-Signal Sλl-8 durchlaufen wird. Die dispersionskompensierende Faser (es kann auch ein breitbandiges gechirptes Fasergitter verwendet werden) ist beispielsweise so dimensioniert, daß zumindest die meisten WDM-Kanäle bzw. Kanalsignale SK1-SK8 leicht un- terkompensiert sind. Dieses vorkompensierte WDM-Signal STλl-8 wird einem Wellenlängendemultiplexer 2 zugeführt, der als Filter für die einzelnen Kanäle bzw. Kanalsignale arbeitet und jedes der teilkompensierten Signale STλl-STλ8 an einem separaten Ausgang abgibt. Die einzelnen Signale werden in Wandlern W1-W8 in analoge oder digitale elektrische Signale umgesetzt und jeweils einem Filter F1-F8 zugeführt. Wenn in Sonderfällen in einem der Kanäle bereits eine optimale Kompensation erfolgt ist, kann das Filter entfallen. Die Filter können als Transversalfilter oder rekursive Filter ausgebil- det sein. Besonders vorteilhaft sind Transversalfilter, da diese sich auch bei im Betrieb befindenden Systemen optimoert werden können.A dispersion-compensating fiber DCFO, through which the WDM signal Sλl-8 passes, is connected to an optical transmission fiber 1. The dispersion-compensating fiber (a broadband chirped fiber grating can also be used) is dimensioned, for example, such that at least most WDM channels or channel signals SK1-SK8 are slightly under-compensated. This precompensated WDM signal STλl-8 is fed to a wavelength demultiplexer 2, which works as a filter for the individual channels or channel signals and outputs each of the partially compensated signals STλl-STλ8 at a separate output. The individual signals are converted into analog or digital electrical signals in converters W1-W8 and each fed to a filter F1-F8. If, in special cases, optimal compensation has already taken place in one of the channels, the filter can be omitted. The filters can be designed as transversal filters or recursive filters. Transversal filters are particularly advantageous because they can also be optimized for systems in operation.
Ein Transversalfilter zweiter Ordnung reicht im allgemeinen für eine zufriedenstellende Kompensation aus. Die Filterkoeffizienten werden aufgrund von Messungen der Signalqualität optimiert. Die kompensierten Signale SKλl bis SKλ8 werden an Ausgängen AI bis A8 - ggf. jeweils über einen Verstärker - einer Abtaststufe oder anderen geeigneten Empfangseinrichtung zugeführt. A second order transverse filter is generally sufficient for satisfactory compensation. The filter coefficients are optimized based on measurements of the signal quality. The compensated signals SKλl to SKλ8 are fed to outputs AI to A8 - possibly via an amplifier in each case - to a sampling stage or other suitable receiving device.

Claims

Patentansprüche claims
1. Anordnung zur kanalindividuellen Dispersionskompensation eines Wellenlängen-Multiplex (WDM) -Signals, bei der dieses in einzelne Kanalsignale (SKI bis SK8) zerlegt wird, die individuell kompensiert werden, d a d u r c h g e k e n n z e i c h n e t , daß ein gemeinsamer Dispersionskompensator (DCFO) vorgesehen ist, dem das WDM-Signal (Sλl-8) zugeführt wird, daß ein Wellenlängen-Demultiplexer (2) vorgesehen ist, dem das derart teilkompensierte WDM-Signal (STλl-8) zugeführt wird, das in einzelne teilkompensierte Kanalsignale (STλl bis STλ8) aufgeteilt wird, daß an die Ausgänge des Wellenlängen-Demultiplexer (2) je- weils ein optoelektrischer Wandler (Wl bis W8) und ein diesem nachgeschaltetes Filter (Fl bis F8) zur Restkompensation angeschaltet ist, so daß daß an Ausgängen (AI bis A8) der Filter kompensierte Signale (SKλl bis SKλδ) abgegeben werden.1. Arrangement for channel-specific dispersion compensation of a wavelength division multiplex (WDM) signal, in which this is broken down into individual channel signals (SKI to SK8), which are individually compensated, characterized in that a common dispersion compensator (DCFO) is provided, which the WDM -Signal (Sλl-8) is supplied that a wavelength demultiplexer (2) is provided, to which the partially compensated WDM signal (STλl-8) is fed, which is divided into individual partially compensated channel signals (STλl to STλ8) that to the outputs of the wavelength demultiplexer (2) an opto-electrical converter (Wl to W8) and a filter (Fl to F8) connected downstream for residual compensation are switched on, so that compensated signals at outputs (AI to A8) (SKλl to SKλδ) are given.
2. Anordnung nach Anspruch 1 , d a d u r c h g e k e n n z e i c h n e t , daß elektrooptische Wandler (Wl, W8) vorgesehen sind, die die teilkompensierten Kanalsignale (STλl bis STλ8) in elektrische Digitalsignale umsetzen, die digitalen Filtern (Fl, F8) zugeführt werden.2. Arrangement according to claim 1, d a d u r c h g e k e n n z e i c h n e t that electro-optical converters (Wl, W8) are provided, which convert the partially compensated channel signals (STλl to STλ8) into electrical digital signals, the digital filters (Fl, F8) are supplied.
3. Anordnung nach Anspruch 1, d a d u r c h g e k e n n z e i c h n e t , daß elektrooptische Wandler (W4) vorgesehen sind, die die teilkompensierten Kanalsignale (STλl bis STλ8) in elektrische Analogsignale umsetzen, die mit analogen Bauelementen realisierten Filtern (F4) zugeführt werden.3. Arrangement according to claim 1, d a d u r c h g e k e n n z e i c h n e t that electro-optical converters (W4) are provided which convert the partially compensated channel signals (STλl to STλ8) into electrical analog signals which are supplied with filters (F4) implemented with analog components.
4. Anordnung nach Anspruch 2 oder 3, d a d u r c h g e k e n n z e i c h n e t , daß Filter (Fl bis F8) zweiter Ordnung vorgesehen sind. 4. Arrangement according to claim 2 or 3, characterized in that filters (Fl to F8) of the second order are provided.
5. Anordnung nach einem der vorhergehenden Ansprüche, d a d u r c h g e k e n n z e i c h n e t , daß als gemeinsamer Dispersionskompensator (DCFO) eine dis- persionskompensierende Faser oder ein breitbandiges gechirp- tes Fasergitter vorgesehen ist.5. Arrangement according to one of the preceding claims, d a d u r c h g e k e n n z e i c h n e t that a dispersion-compensating fiber or a broadband chirped fiber grating is provided as a common dispersion compensator (DCFO).
6. Anordnung nach Anspruch 5, d a d u r c h g e k e n n z e i c h n e t , daß ein gemeinsamer Dispersionskompensator (DCFO) vorgesehen ist, der eine geringfügige Unterkompensation des der einzelnen Kanalsignale bewirkt. 6. Arrangement according to claim 5, so that a common dispersion compensator (DCFO) is provided, which causes a slight undercompensation of the individual channel signals.
PCT/DE2000/000661 1999-03-24 2000-03-02 Device for channel-specific dispersion compensation of a wavelength multiplex signal WO2000057584A1 (en)

Priority Applications (3)

Application Number Priority Date Filing Date Title
JP2000607360A JP2002540676A (en) 1999-03-24 2000-03-02 Apparatus for dispersion-compensating wavelength division multiplexed signal for each channel
AU35507/00A AU3550700A (en) 1999-03-24 2000-03-02 Device for channel-specific dispersion compensation of a wavelength multiplex signal
EP00914055A EP1161804A1 (en) 1999-03-24 2000-03-02 Device for channel-specific dispersion compensation of a wavelength multiplex signal

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Application Number Priority Date Filing Date Title
DE19913374.3 1999-03-24
DE19913374A DE19913374C2 (en) 1999-03-24 1999-03-24 Arrangement for channel-specific dispersion compensation of a wavelength division multiplex signal

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WO (1) WO2000057584A1 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101160757B (en) * 2005-04-28 2012-05-30 斯欧普迪克尔股份有限公司 Common electronic dispersion compensation arrangement for use with multiple optical communication channels

Families Citing this family (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6829549B2 (en) * 2001-12-17 2004-12-07 Nortel Networks Limited Implementation of a post detection chromatic dispersion compensation transfer function
US6775631B2 (en) 2001-12-17 2004-08-10 Nortel Networks Limited Post detection chromatic dispersion compensation
JP2003298516A (en) 2002-03-29 2003-10-17 Fujitsu Ltd Wavelength dispersion compensation apparatus
FR2842676B1 (en) * 2002-07-18 2007-07-20 Cit Alcatel METHOD FOR MAKING AND IMPROVING AN OPTICAL TRANSMISSION LINE AND ASSOCIATED COMPENSATION MODULES
JP4530143B2 (en) * 2004-07-28 2010-08-25 日本電気株式会社 Optical communication apparatus, optical transmission system, and optical transmission method
FR2932932B1 (en) * 2008-06-23 2010-08-13 Draka Comteq France Sa MULTIPLEX WAVE LENGTH OPTIC SYSTEM WITH MULTIMODE OPTIC FIBERS
CN101826921B (en) * 2009-03-06 2014-09-17 华为技术有限公司 Chromatic dispersion gradient compensation method and device

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5430568A (en) * 1992-12-01 1995-07-04 Scientific-Atlanta, Inc. Optical communications system for transmitting information signals having different wavelengths over a same optical fiber
US5642215A (en) * 1994-09-12 1997-06-24 Kokusai Denshin Denwa Kabushiki Kaisha Optical transmission system
DE19602433A1 (en) * 1996-01-24 1997-07-31 Siemens Ag Dispersion compensating circuit arrangement for multiplexed optical transmission system
EP0884867A2 (en) * 1997-06-09 1998-12-16 Nortel Networks Corporation Equalisation, pulse shaping and regeneration of optical signals

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5430568A (en) * 1992-12-01 1995-07-04 Scientific-Atlanta, Inc. Optical communications system for transmitting information signals having different wavelengths over a same optical fiber
US5642215A (en) * 1994-09-12 1997-06-24 Kokusai Denshin Denwa Kabushiki Kaisha Optical transmission system
DE19602433A1 (en) * 1996-01-24 1997-07-31 Siemens Ag Dispersion compensating circuit arrangement for multiplexed optical transmission system
EP0884867A2 (en) * 1997-06-09 1998-12-16 Nortel Networks Corporation Equalisation, pulse shaping and regeneration of optical signals

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101160757B (en) * 2005-04-28 2012-05-30 斯欧普迪克尔股份有限公司 Common electronic dispersion compensation arrangement for use with multiple optical communication channels

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JP2002540676A (en) 2002-11-26
AU3550700A (en) 2000-10-09
DE19913374A1 (en) 2000-10-19
EP1161804A1 (en) 2001-12-12
CN1345491A (en) 2002-04-17

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