WO2010094340A1 - Connexion transversale photonique dotée de compensation de dispersion sélectable - Google Patents

Connexion transversale photonique dotée de compensation de dispersion sélectable Download PDF

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Publication number
WO2010094340A1
WO2010094340A1 PCT/EP2009/052079 EP2009052079W WO2010094340A1 WO 2010094340 A1 WO2010094340 A1 WO 2010094340A1 EP 2009052079 W EP2009052079 W EP 2009052079W WO 2010094340 A1 WO2010094340 A1 WO 2010094340A1
Authority
WO
WIPO (PCT)
Prior art keywords
add
signals
drop
wdm
connect
Prior art date
Application number
PCT/EP2009/052079
Other languages
English (en)
Inventor
Robert Schimpe
Original Assignee
Nokia Siemens Networks Oy
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 Nokia Siemens Networks Oy filed Critical Nokia Siemens Networks Oy
Priority to PCT/EP2009/052079 priority Critical patent/WO2010094340A1/fr
Publication of WO2010094340A1 publication Critical patent/WO2010094340A1/fr

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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
    • H04J14/0201—Add-and-drop multiplexing
    • H04J14/0202—Arrangements therefor
    • H04J14/0213—Groups of channels or wave bands arrangements
    • 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
    • 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
    • H04J14/0208—Interleaved 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
    • H04J14/0209—Multi-stage arrangements, e.g. by cascading multiplexers or demultiplexers
    • 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
    • H04J14/021—Reconfigurable arrangements, e.g. reconfigurable optical add/drop multiplexers [ROADM] or tunable optical add/drop multiplexers [TOADM]
    • 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
    • H04J14/021—Reconfigurable arrangements, e.g. reconfigurable optical add/drop multiplexers [ROADM] or tunable optical add/drop multiplexers [TOADM]
    • H04J14/0212—Reconfigurable arrangements, e.g. reconfigurable optical add/drop multiplexers [ROADM] or tunable optical add/drop multiplexers [TOADM] using optical switches or wavelength selective switches [WSS]
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04J—MULTIPLEX COMMUNICATION
    • H04J14/00—Optical multiplex systems
    • H04J14/02—Wavelength-division multiplex systems
    • H04J14/0221—Power control, e.g. to keep the total optical power constant
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04Q—SELECTING
    • H04Q11/00—Selecting arrangements for multiplex systems
    • H04Q11/0001—Selecting arrangements for multiplex systems using optical switching
    • H04Q11/0005—Switch and router aspects
    • 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
    • H04J14/0204—Broadcast and select arrangements, e.g. with an optical splitter at the input before adding or 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
    • H04J14/0202—Arrangements therefor
    • H04J14/0205—Select and combine arrangements, e.g. with an optical combiner at the output after adding or dropping
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04Q—SELECTING
    • H04Q11/00—Selecting arrangements for multiplex systems
    • H04Q11/0001—Selecting arrangements for multiplex systems using optical switching
    • H04Q11/0005—Switch and router aspects
    • H04Q2011/0037—Operation
    • H04Q2011/0039—Electrical control
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04Q—SELECTING
    • H04Q11/00—Selecting arrangements for multiplex systems
    • H04Q11/0001—Selecting arrangements for multiplex systems using optical switching
    • H04Q11/0005—Switch and router aspects
    • H04Q2011/0037—Operation
    • H04Q2011/0049—Crosstalk reduction; Noise; Power budget

Definitions

  • the invention refers to a photonic cross-connect with selectable dispersion compensation.
  • Dispersion compensation for Wavelength Division Multiplex (WDM) ultra-long-haul network can be optimized for specific modulation formats, e.g. 40Gb/s Differential-Phase-Shift- Keying or On-Off-Keying.
  • the dispersion compensation modules (DC) are placed in the mid-stage of preamplifier and booster amplifier, and thereby are common to all incoming and outgoing channels of a WDM signal for each transmission direction.
  • DC dispersion compensation modules
  • a photonic cross-connect with a receiving part for incoming WDM signals, with a transmitting part for outgoing WDM signals, and with add-drop-facuities, the receiving part of a cross connect section (PXC) having at least two drop outputs for outputting intermediate WDM-drop- signals comprising selected channels of received WDM-signals requiring a similar dispersion post-compensation, at least two drop paths, each connected to an drop output and comprising a wavelength division demultiplexer, whereas at least one drop path comprises a dispersion compensator inserted upstream of the wavelength division demultiplexer.
  • PXC cross connect section
  • the economical advantage is gained by restricting the number of different options of dispersion compensation.
  • the channels of the received WDM signals are selected according to the compensation requirements, combined to intermediate WDM-drop- signals are compensated together.
  • the flexibility for per-channel compensation is restricted for economical reasons.
  • a photonic cross-connect with a receiving part for incoming WDM signals, with a transmitting part for outgoing WDM signals, and with add-drop-facuities, comprising at least two add paths, each connected to an add input of the cross connect section, and comprising a wavelength division multiplexer receiving and combining add chan- nels requiring a similar dispersion pre-compensation to intermediate WDM-add-signals, whereas at least one add path comprises a dispersion pre-compensator inserted downstream the wavelength division multiplexer, and the transmitting part having at least two add inputs receiving said intermedi- ate WDM-add-signals, wherein the transmitting part is designed for selecting add signals of said intermediate WDM- add-signals and outputting WDM signals including the selected add signals. Therefore per-channel selectable pre-compensation is per- formed in the transmitting part with a restricted number of dispersion compensators.
  • the photonic cross-connect can further comprise basic disper- sion compensators arranged upstream of inputs of the receiving part of the cross connect section implemented for basic dispersion compensation of the received WDM signals.
  • the photonic cross-connect should further comprise basic dis- persion pre-compensators arranged downstream of outputs of the transmitting part of the cross connect section implemented for basic dispersion pre-compensation of the transmitted WDM signals.
  • the basic dispersion and basic pre-dispersion compensators are adapted to the transmission lines, while the dispersion compensators in the drop and in the add paths are adapted e.g. to specific needs related to different transmission rates and modulation formats and less dispersion has to be compensated in the add or the drop path.
  • FIG 1 shows a simplified diagram of photonic cross-connect with add-drop-facuities
  • FIG 2 shows an example of an embodiment of the photonic cross-connect with cross-connect-facuities and add-drop- regeneration facilities
  • FIG 3 shows examples of replaceable components. DETAILED DESCRIPTION OF THE INVENTION
  • FIG 1 shows the simplified diagram of a photonic cross- connect according to the invention.
  • the cross-connect-section PXC receives at line inputs a plurality of wavelength division multiplex (WDM) signals WRl - WR3.
  • WDM wavelength division multiplex
  • Each WDM signal consists of a plurality of optical signals with different wavelengths. These signals are often referred to as channels. Here are signals and channels also used as synonyms.
  • Single signals of each WDM signal are individually or as a group forwarded to outgoing WDM signals WTl - WT3 and transmitted at line outputs in other directions. Other optical signals are dropped or new signals are added.
  • the inventive idea is first to separate the incoming channels, second to combine those channels, which are suited for the same mode and/or amount of dispersion compensation (including also no dispersion compensation) to intermediate WDM- drop-signals WIRO, WIRl, WIR2, and third to compensate each intermediate WDM-drop-signal according to dispersion requirements .
  • a simplified add-drop-regenerator-section ADR shows two drop paths and two add paths.
  • a first common dispersion compensator DCRl is used for compen- sating the first intermediate WDM-drop-signal WIRl.
  • the channels of the compensated first intermediate WDM-drop-signal WIRl are separated by a wavelength division demultiplexers DXl and the drop-signals DSl, ..., DFl, ... (only two are shown for clarity reasons) are output to subscribers or to regenerators REGl, ....
  • DX2 DX2, SMR2
  • a second dispersion compensator DCR2 is used for compensating the second intermediate WDM-drop-signal WIR2.
  • the channels are separated by a second wavelength division demultiplexer DX2, and compensated drop signals
  • DS2 ... are transmitted via a switching matrix SMR2 and add- drop-terminals ADT2, ... to subscribers and the drop signals DF2, ... to a further regenerators REG2, ....
  • SMR2 switching matrix
  • ADT2 add- drop-terminals
  • DF2 drop signals
  • REG2 regenerators
  • Basic dispersion compensators DRl - DR3 are arranged upstream of inputs of a receiving part of the PXC. They are used to perform basic dispersion compensation and adapted to the transmission lines.
  • Basic dispersion pre-compensators DTl - DT3 are arranged downstream the line outputs of the transmitting part of the transmitting part of the PXC. These pre-compensators are also adapted to the transmission lines.
  • the pre-compensators DTl - DT3 may be used for pre- compensation of the outgoing signals. But for an optimized performance an adequate dispersion pre-compensation has to be executed also for the outgoing signals.
  • the add signals are combined by multiplexers MXl, MX2 to intermediate WDM-add-signals WITl, WIT2, ... and pre- compensated by dispersion pre-compensators DCTl in the first add path MXl-DCTl and DCT2 in the second add path MX2-DCT2- SMT2 respectively.
  • the second add path includes a switching matrix SMT2 according to the switching matrix in the second drop path allowing high switching flexibility.
  • the pre-compensated WDM-add-signals are fed to add inputs of the PXC. Therefore an outgoing WDM signal can contain forwarded signals without or with regeneration as well as pre_compensated add signals ASl, AS2, .... and also not pre_compensated add signals (FIG 2) .
  • Express channels or express WDM signals within intermediate WDM-drop-signals WIRO may be dispersion compensated by express dispersion compensation units DCE. These dispersion compensation units are also advantageously combined with amplifiers as shown in the drawing.
  • FIG 2 shows a preferred embodiment of the photonic cross- connect comprising in the cross-connect-section PXC a first group of wavelength-selective switches (WSSs) WSRl - WSR3 in an incoming part and a second group WSTl - WST3 in an outgoing part of the PXC to establish photonic cross-connect- facilities and add-drop-functionality .
  • WSSs wavelength-selective switches
  • each WSS WSRl - WSR3 receives one WDM signal WRl - WR3.
  • Cross connect outputs of the WSRl - WSR3 are connected directly to "cross connect inputs" of the wavelength-selective switches WSTl - WST3 of a transmitter part to enable direct cross-connect functionality. Therefore a selectable number of channels of the WDM signals WRl - WR3 can be switched directly to the WSSs WSTl - WST3 at the transmitting section.
  • Each signal distributing WSS WSRl - WSR3 has at least one or more drop outputs.
  • the drop outputs of WSRl - WSR3 are connected to inputs of a first combiner CMl and additional drop outputs of WSR2 and WSR3 are connected to inputs of a second combiner CM2 (or further combiners) .
  • Each WSTl - WST3 of the second group has one or more add in- puts, which are connected to outputs of a first splitter SPl and to outputs of a second splitter SP2 (or further splitters) .
  • CMl and CM2 could be WSSs.
  • SPl and SP2 could be WSS. This replacement does not change the PXC architecture.
  • FIG 2 also shows a special embodiment of the demultiplexer unit DXl.
  • the demultiplexer unit comprises a deinterleaver DI separating the odd and the even channels (standard grid and offset grid channels) . Therefore each group can be dispersion compensated differently by dispersion compensators DCRIl and DCR12 according to the system requirements.
  • a common dispersion compensator DCRl (dashed) can be used if separate compensation is not necessary.
  • Second drop outputs of the WSR2 is directly connected - or connected together with an output of WSR3 via inputs of a second combiner (or architectural equivalent WSS) CM2 (dashed lines) - to the second demultiplexer unit DX2.
  • the second drop path may contain a different DC-unit or - as shown in this figure - even none, if the basic DC compensation is sufficient for the associated channels.
  • the add paths correspond to the drop paths.
  • the first multi- plexer unit MXl comprises two wavelength division sub- multiplexers MXIl and MX12, whose inputs are connected to the add-drop-terminals ADTl, ADT2, ... or to regenerator terminals REGl.
  • the outputs of the sub-multiplexers MXIl and MX12 are connected via dispersion compensators DCTIl and DCT12 to inputs of an interleaver IN, whose output is connected via a first splitter SPl to add-inputs of WSTl - WST3.
  • the second add path comprises the second multiplexer unit MX2, whose inputs are also connected to the add-drop- terminals ADTl, ADT2, ... or to regenerator terminals REGl, REG2.
  • the output of MX2 is directly connected to an add input of WST2 or e.g. via the second splitter SP2 (dashed) con- nected to add inputs of the WST2 and the WST3 respectively.
  • the second drop path contains a different dispersion pre- compensating unit DCT2 or - as shown - even none, if the basic DC compensation is sufficient.
  • the dispersion compensation in the receiver section is carried out advantageously in two steps as mentioned before.
  • An adequate two step dispersion pre-compensation can be executed in the transmitting section.
  • the outputs of the demultiplexers DXl (DXIl, DX12) and DX2 and the inputs of the multiplexers MXl (MXIl, MX12) and MX2 are not only connected to add-drop-terminals ADTl, ADT2, ... but also to regenerator terminals REGl for individual channel compensation. Therefore not only add-drop-functionality but also regeneration is possibly for selected channels.
  • a bidirectional Regenerator terminal can be realized also by back-to- back connection of two Add-drop terminals. E.g. by feeding ADTl (ADT2) signal DSl (DS2) as AS2 (ASl) into ATD2 (ADTl) . More generally the add-drop terminals (ADTl, ADT2, ...) can be the line interfaces of an electrical cross-connect, e.g. an ODU cross-connect.
  • a management system (not shown) is also necessary, which takes care that only channels with similar dispersion and with different wavelengths are selected to form the intermediate WDM signals WIRIl, WIR12, WIR2 and the transmitted WDM signals WTl, WT2, WT3.
  • the dispersion may be calculated or measured and stored in a look-up table for different connections .
  • Additional switching matrices can be inserted in the firth drop path, or in the first add path.
  • Preferentially tunable demultiplexers and multiplexers are employed instead of shown in the second drop and the second ad path.
  • one group of the WSSs in the PXC may be replaced by splitters or combiners.
  • the splitter and combiners in FIG 2 can also be replaced by WSSs.
  • a WSSs (WSRl) can be replaced by a splitter.
  • a WSSs (WST2) can be replaced by a combiner (while in the related receiving part the WSS (WSR2) remains as shown.
  • a selection of replaceable elements is shown in FIG 3.
  • a Splitter SP / combiner CM and multiplexer MUX / demultiplexer DMUX and also a combination of MUX/DEMUX and a switching matrix can be replaced by a WSS, as known to those skilled in the art. Also tunable multiplexers or demultiplexers can be applied.
  • DCRl DCR2 first, second dispersion compensator (RX) DCTl, DCT2 first, second pre-compensator (TX)

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  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Optical Communication System (AREA)

Abstract

La présente invention concerne une connexion transversale photonique dotée d'une partie réception destinée à recevoir des signaux WDM entrants (WR1-WR3) et une partie émission permettant d'émettre des signaux WDM sortants (WT1-WT3), une section de connexion transversale (PXC) dispose d'au moins deux sorties d'extraction permettant d'extraire des signaux d'extraction WDM intermédiaires (WIR1, WIR2) comprenant des canaux sélectionnés de signaux WDM (WR1-WR3) reçus exigeant une compensation de dispersion similaire, et au moins deux chemins d'extraction (DCR1-DX1, DCR2-DX2) comprenant des compensateurs de dispersion (DCR1, DCR2) et au moins deux chemins d'ajout (MX1-DCT1, MX2-DCT2) pour une pré-compensation de signaux d'ajout WDM intermédiaires (WIT1, WIT2) qui sont ajoutés aux signaux WDM émis (WT1-WT3).
PCT/EP2009/052079 2009-02-20 2009-02-20 Connexion transversale photonique dotée de compensation de dispersion sélectable WO2010094340A1 (fr)

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Application Number Priority Date Filing Date Title
PCT/EP2009/052079 WO2010094340A1 (fr) 2009-02-20 2009-02-20 Connexion transversale photonique dotée de compensation de dispersion sélectable

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PCT/EP2009/052079 WO2010094340A1 (fr) 2009-02-20 2009-02-20 Connexion transversale photonique dotée de compensation de dispersion sélectable

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Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20010024544A1 (en) * 2000-03-22 2001-09-27 Tadashi Matsuoka Optical transmission system and optical coupler/branching filter
WO2002013425A1 (fr) * 2000-08-10 2002-02-14 Siemens Aktiengesellschaft Dispositif optique d'insertion-extraction et de compensation de dispersion
US20030058497A1 (en) * 2001-09-27 2003-03-27 Nortel Networks Limited All-optical switching sites for an agile optical network
EP1622298A2 (fr) * 2004-07-28 2006-02-01 NEC Corporation Dispositif de communication optique, système de communication optique et procédé pour la transmission d'un signal optique

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20010024544A1 (en) * 2000-03-22 2001-09-27 Tadashi Matsuoka Optical transmission system and optical coupler/branching filter
WO2002013425A1 (fr) * 2000-08-10 2002-02-14 Siemens Aktiengesellschaft Dispositif optique d'insertion-extraction et de compensation de dispersion
US20030058497A1 (en) * 2001-09-27 2003-03-27 Nortel Networks Limited All-optical switching sites for an agile optical network
EP1622298A2 (fr) * 2004-07-28 2006-02-01 NEC Corporation Dispositif de communication optique, système de communication optique et procédé pour la transmission d'un signal optique

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
AJGAONKAR M ET AL: "Transparent ultra-long-haul DWDM networks with broadcast-and-select OADM/OXC architecture", JOURNAL OF LIGHTWAVE TECHNOLOGY, IEEE SERVICE CENTER, NEW YORK, NY, US, vol. 21, no. 11, 1 November 2003 (2003-11-01), pages 2661 - 2672, XP011103944, ISSN: 0733-8724 *

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