WO1998054854A1 - Modulation format adjusting optical transponders - Google Patents
Modulation format adjusting optical transponders Download PDFInfo
- Publication number
- WO1998054854A1 WO1998054854A1 PCT/US1998/009932 US9809932W WO9854854A1 WO 1998054854 A1 WO1998054854 A1 WO 1998054854A1 US 9809932 W US9809932 W US 9809932W WO 9854854 A1 WO9854854 A1 WO 9854854A1
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- WO
- WIPO (PCT)
- Prior art keywords
- optical
- modulation
- modulation format
- signal
- information
- Prior art date
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Classifications
-
- 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
- H04B10/29—Repeaters
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04J—MULTIPLEX COMMUNICATION
- H04J14/00—Optical multiplex systems
- H04J14/02—Wavelength-division multiplex systems
Definitions
- the invention relates to optical transponders generally and, more particularly, to optical transponders which change the modulation format of incident optical signals.
- optical communication systems are a substantial constituent of communication networks.
- the expression "optical communication system,” as used herein, relates to any system which uses optical signals to convey information across an optical waveguiding medium.
- Such optical systems include, but are not limited to, telecommunications systems, cable television systems, and local area networks (LANs).
- LANs local area networks
- Optical systems are described in Gowar, Ed. Optical Communication Systems. (Prentice Hall, NY) c. 1993, the disclosure of which is incorporated herein by reference.
- Optical transmitters are typically available in a particular modulation format.
- wavelength division multiplexing In some optical systems wavelength division multiplexing (WDM) is employed to increase the capacity of the fiber optic network.
- WDM wavelength division multiplexing
- plural optical channels are carried over a single waveguide, each channel being assigned a particular wavelength.
- U.S. 5,504,609 and serial number 08/624,269 the disclosures of which are incorporated herein by reference, a series of optical remodulators are used to take input signals from various optical transmitters and output the information onto optical channels within the channel plan of a WDM optical system.
- the modulation formats of the optical signals output by the optical transmitters and the remodulators is the same. However, depending upon the type of optical receivers employed and the transmission characteristics of the optical system, it may be desirable to change the modulation format of the optical transmitters to a format which is better suited to transmission in the WDM optical system.
- optical transponders which can change the modulation format of incident optical signals.
- WDM optical communication systems which can receive incoming optical transmitter signals of various modulation formats and place the information onto WDM system optical channels in a different modulation format from that of the transmitter optical signals.
- the present invention provides a modulation format adjusting optical transponder for receiving an incident optical signal of a first modulation format and outputting an optical signal having a different modulation format.
- the transponder includes an optical-to- electrical conversion element configured to receive an information-bearing optical signal having a first modulation format and output an electrical signal corresponding to information from the incident optical signal.
- the transponder includes a laser for outputting an optical carrier signal at a selected wavelength and a modulator communicating with the optical-to-electrical conversion element and with the laser. The modulator places the information from the incident optical signal onto the optical signal output by the laser, creating a modulated optical output signal having a second modulation format different from the first modulation format.
- the optical transponders of the present invention can take optical signals in a common modulation format, such as amplitude modulation, and output optical signals in a power- flat modulation format, such as frequency shift key (FSK) modulation.
- the modulation format adjusting optical transponders of the present invention can be used as remodulators for wavelength division multiplexed optical systems.
- FIG. 1 schematically depicts a modulation format adjusting optical transponder according to the present invention.
- FIG. 2 schematically depicts a wavelength division multiplexed optical communication system employing the optical transponder of FIG. 1 as an optical remodulator.
- FIG. 1 schematically depicts a modulation format adjusting optical transponder 30 according to the present invention.
- Transponder 30 receives an optical signal output by an optical transmitter.
- the input optical signal is converted by optoelectronic converter 32, typically a photodiode, to an electrical signal.
- the resultant electrical signal is amplified by amplifier 34, and routed through clock and data recovery circuit 35. Following retiming, the electrical signal passes to modulator driver 39 which drives modulator 38.
- Transponder 30 includes an optical source, such as laser 36, for delivering a non- information-bearing optical carrier signal to the laser output waveguide.
- laser 36 is a DFB semiconductor diode laser, generally comprising one or more ⁇ l-V semiconductor materials, commercially available from a wide variety of suppliers such as Fujitsu, GEC Marconi, and Hewlett-Packard.
- the laser outputs an optical carrier signal at a particular optical wavelength, ⁇ , (which, in the case of a WDM optical system, is a wavelength corresponding to a demultiplexer wavelength included in a receiving system).
- Laser driver 37 provides the required laser bias current through a suitable power supply (not shown) as well as thermal control of the laser wavelength.
- An optical wave in a single mode fiber of a certain center frequency has three parameters which can continuously vary with time: amplitude, phase (frequency), and state of polarization. What is meant by "modulation format" is that one of these attributes, or a coupled combination of these, is made to vary in accordance with the information being imparted to that optical wave. The other parameters are not constrained to follow the information signal.
- Modulator 38 uses a modulation format different from the modulation format of the optical signal input to optoelectronic converter 32.
- modulation format refers to the variation of one or more optical parameters such as amplitude, phase (frequency), and state of polarization to impart information to a carrier optical signal.
- the incident optical signals are amplitude modulated.
- transponders 30 can employ modulators with power flat modulation formats such as frequency shift key (FSK) or polarization shift key (PolSK) to create optical signals which do not create time-dependent power variations within the optical system.
- FSK frequency shift key
- PolSK polarization shift key
- a particularly preferred modulation format creates a non-zero chirped optical signal, a modulation format which varies both the amplitude and phase of the optical signal.
- incident amplitude- modulated optical signals from optical transmitters can be converted to optical signals with a power-flat modulation format.
- the invention encompasses any transponder which uses a modulator having a modulation format, whether amplitude, frequency, phase, or polarization based (or a combination thereof), which is different from the modulation format of the incident optical signal.
- modulation formats are described in further detail in the Gowar reference, cited above, and in Schwartz, Information. Transmission. Modulation, and Noise. (McGraw-Hill, New York), c. 1990, the disclosure of which is incorporated by reference herein.
- FIG. 2 depicts a wavelength division multiplexed optical communication system 10 employing the modulation format adjusting transponders of FIG. 1 as optical remodulators.
- Optical communication system 10 takes optical transmission signals from diverse optical transmitters and other optical signal sources and maps the signal sources onto a wavelength division optical communication system, i.e., a communication system in which individual optical signals correspond to optical channels within a wavelength division multiplexed optical signal carried on an optical waveguide.
- optical transmitters 20 are used to provide the information that will be carried by the optical channels within the WDM optical system.
- Optical transmitters 20 generally includes a laser, such as a DFB semiconductor laser, and a modulator for creation of an information-bearing optical signal.
- optical signal refers to an optical signal which has been coded with information, including, but not limited to, audio signals, video signals, and computer data, generally through modulation.
- the laser of optical transmitter 10 can be directly modulated. Because some of the transmitters may form part of an existing optical system, a wide variety of transmitters emitting in a broad range of wavelengths can be accommodated in the optical communication system of the present invention, thus ensuring compatibility with currently- deployed transmission equipment. Typical transmitters emit wavelengths ranging from about 1300 to 1600 nm. Transmitters in current optical communication systems and various optical modulation techniques employed therein are described in Gowar, Optical Communication Systems, incorporated by reference above. Optical transmitters suitable for use in the present invention are commercially available from NEC, Fujitsu, Alcatel, and Nortel.
- Optical communication system 10 uses the modulation format adjusting transponders 30 of FIG. 1 as remodulators 130 for receiving the transmitted information- bearing optical signal and outputting an information-bearing optical signal at a WDM
- optical system channel wavelength ⁇ optical system channel wavelength ⁇ ,.
- the subscript j ranges from 1 to 16 for the exemplary
- the optical system of FIG. 1 can also be, for example, 4, 8, or 32 depending upon the capacity needs of the optical route services by the system.
- the wavelengths emitted by the remodulators are selected to be within the 1500 nanometer range, the range in which the minimum signal attenuation occurs for silica-based fibers. More particularly, the wavelengths emitted by the remodulators are selected to be in the range from 1530 to 1560 nanometers. However, other wavelength bands may be selected according to overall system requirements.
- Each optical channel is routed to optical combiner 50 for conveyance to optical waveguide 60.
- Optical combiner 50 is selected from any passive optical component which can combine plural wavelengths into a single output medium. Frequently, optical splitters used to divide a signal among plural outputs are used as optical combiners, operated in reverse fashion from the splitter. Exemplary optical combiners include 1 x N passive splitters available from Corning, Inc., Corning, NY, 1 x N wideband single mode splitters available from IOT Integrator Optik GmbH, Waghausel-Kirrlach, Germany, and fused fiber combiners available from Gould, Inc., Millersville, MD. The combination of channels forms a multiplexed optical signal which is output to waveguide 60.
- Optical waveguide 60 is typically a single-mode optical fiber such as SMF-28, available from Corning, and TRUEWAVE, available from AT&T Corp./Lucent Technologies, and is the principal transmission medium for the optical communication system.
- any optical waveguide which is capable of transporting multiple optical wavelengths can be employed as waveguide 60 in optical system 10.
- Optionally interposed along optical waveguide 60 are one or more optical amplifiers
- Optical amplifiers 70 are selected from any device which directly increases the strength of plural optical signals without the need for optical-to-electrical conversion.
- optical amplifiers 70 are selected from optical waveguides doped with rare earth ions such as erbium, neodymium, praseodymium, ytterbium, or mixtures thereof.
- rare earth ions such as erbium, neodymium, praseodymium, ytterbium, or mixtures thereof.
- Optical amplifiers, their materials , and their operation are further described in Gowar, Ed. Optical Communication Systems, incorporated by reference above and in Desurvire, Erbium-Doped Fiber Amplifiers. (John Wiley & Sons, Inc., NY), c. 1994, and Bjarklev, Optical Fiber Amplifiers: Design and System Applications.
- each channel Following transmission and amplification of the multiplexed optical signals along waveguide 60, each channel must be demultiplexed and routed to the receiver designated for the particular ⁇ j channel.
- the multiplexed signal is input to optical splitter 80 which places a portion of the multiplexed signal onto plural output paths 82.
- Each output path 82 optically communicates with a receiving system 90.
- Optical splitter 80 is selected from any optical device which can divide an input optical signal and place it onto plural output paths. Exemplary splitters include passive optical components such as those components described for use as optical combiner 50.
- Receiving systems 90 typically include wavelength selectors (not shown) for selecting the particular channel, ⁇ j from the multiplexed signal and
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- Electromagnetism (AREA)
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Optical Communication System (AREA)
Abstract
Description
Claims
Priority Applications (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
AU76862/98A AU7686298A (en) | 1997-05-29 | 1998-05-29 | Modulation format adjusting optical transponders |
DE69831941T DE69831941T2 (en) | 1997-05-29 | 1998-05-29 | MODULATION FORMAT ADJUSTING OPTICAL TRANSPONDER |
EP98924772A EP0981869B1 (en) | 1997-05-29 | 1998-05-29 | Modulation format adjusting optical transponders |
CA002291610A CA2291610A1 (en) | 1997-05-29 | 1998-05-29 | Modulation format adjusting optical transponders |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US08/862,930 US6101011A (en) | 1997-05-29 | 1997-05-29 | Modulation format adjusting optical transponders |
US08/862,930 | 1997-05-29 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO1998054854A1 true WO1998054854A1 (en) | 1998-12-03 |
Family
ID=25339770
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/US1998/009932 WO1998054854A1 (en) | 1997-05-29 | 1998-05-29 | Modulation format adjusting optical transponders |
Country Status (6)
Country | Link |
---|---|
US (2) | US6101011A (en) |
EP (1) | EP0981869B1 (en) |
AU (1) | AU7686298A (en) |
CA (1) | CA2291610A1 (en) |
DE (1) | DE69831941T2 (en) |
WO (1) | WO1998054854A1 (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
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WO2013091706A1 (en) * | 2011-12-22 | 2013-06-27 | Telefonaktiebolaget L M Ericsson (Publ) | Muxponder and method of converting a plurality of tributary optical communications signals having a first bit rate into an optical line signal having a second, higher bit rate |
Families Citing this family (35)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6101011A (en) * | 1997-05-29 | 2000-08-08 | Ciena Corporation | Modulation format adjusting optical transponders |
US6583905B1 (en) * | 1998-05-30 | 2003-06-24 | Cisco Photonics Italy S.R.L. | Apparatus and method for reducing SPM/GVD in optical systems |
US6717201B2 (en) * | 1998-11-23 | 2004-04-06 | Micron Technology, Inc. | Capacitor structure |
US6721508B1 (en) | 1998-12-14 | 2004-04-13 | Tellabs Operations Inc. | Optical line terminal arrangement, apparatus and methods |
US7031612B2 (en) * | 2000-07-18 | 2006-04-18 | Multiplex, Inc. | Optical transponders and transceivers |
WO2002037721A1 (en) * | 2000-10-30 | 2002-05-10 | Pharmaseq, Inc. | Method and apparatus for a photo-activated transponder |
US20040197101A1 (en) * | 2001-02-05 | 2004-10-07 | Sasser Gary D. | Optical transceiver module with host accessible on-board diagnostics |
US7346278B2 (en) * | 2001-02-05 | 2008-03-18 | Finisar Corporation | Analog to digital signal conditioning in optoelectronic transceivers |
US7149430B2 (en) * | 2001-02-05 | 2006-12-12 | Finsiar Corporation | Optoelectronic transceiver having dual access to onboard diagnostics |
US7302186B2 (en) * | 2001-02-05 | 2007-11-27 | Finisar Corporation | Optical transceiver and host adapter with memory mapped monitoring circuitry |
US7079775B2 (en) * | 2001-02-05 | 2006-07-18 | Finisar Corporation | Integrated memory mapped controller circuit for fiber optics transceiver |
AU2002257061A1 (en) * | 2001-03-16 | 2002-10-03 | Photuris, Inc. | Wavelength division multiplexed optical communication system having a reconfigurable optical switch and a tunable backup laser transmitter |
CN1596517A (en) * | 2001-03-16 | 2005-03-16 | 福图瑞斯有限公司 | Modular all-optical cross-connect |
US7068948B2 (en) * | 2001-06-13 | 2006-06-27 | Gazillion Bits, Inc. | Generation of optical signals with return-to-zero format |
US6975642B2 (en) | 2001-09-17 | 2005-12-13 | Finisar Corporation | Optoelectronic device capable of participating in in-band traffic |
US6862302B2 (en) * | 2002-02-12 | 2005-03-01 | Finisar Corporation | Maintaining desirable performance of optical emitters over temperature variations |
US7437079B1 (en) | 2002-06-25 | 2008-10-14 | Finisar Corporation | Automatic selection of data rate for optoelectronic devices |
US7486894B2 (en) * | 2002-06-25 | 2009-02-03 | Finisar Corporation | Transceiver module and integrated circuit with dual eye openers |
US7664401B2 (en) * | 2002-06-25 | 2010-02-16 | Finisar Corporation | Apparatus, system and methods for modifying operating characteristics of optoelectronic devices |
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US7230961B2 (en) | 2002-11-08 | 2007-06-12 | Finisar Corporation | Temperature and jitter compensation controller circuit and method for fiber optics device |
EP1475914B1 (en) * | 2003-05-05 | 2006-03-22 | Alcatel | Network element for use in an optical communication network, in particular a DWDM communication network |
US7426586B2 (en) * | 2003-12-15 | 2008-09-16 | Finisar Corporation | Configurable input/output terminals |
JP4284199B2 (en) * | 2004-01-26 | 2009-06-24 | 株式会社日立コミュニケーションテクノロジー | Optical cross-connect device and network management device |
US7373090B2 (en) * | 2004-03-26 | 2008-05-13 | Intel Corporation | Modulator driver circuit with selectable on-chip termination |
US7630631B2 (en) * | 2004-04-14 | 2009-12-08 | Finisar Corporation | Out-of-band data communication between network transceivers |
US7447438B2 (en) * | 2004-07-02 | 2008-11-04 | Finisar Corporation | Calibration of digital diagnostics information in an optical transceiver prior to reporting to host |
US8639122B2 (en) * | 2004-07-02 | 2014-01-28 | Finisar Corporation | Filtering digital diagnostics information in an optical transceiver prior to reporting to host |
US7532820B2 (en) | 2004-10-29 | 2009-05-12 | Finisar Corporation | Systems and methods for providing diagnostic information using EDC transceivers |
US8204374B2 (en) * | 2004-12-10 | 2012-06-19 | Ciena Corporation | Reconfigurable multichannel (WDM) optical ring network with optical shared protection |
US20090245813A1 (en) * | 2008-03-31 | 2009-10-01 | Kitel Technologies Llc | Modulator driver with multi-channel active alignment |
US8159956B2 (en) | 2008-07-01 | 2012-04-17 | Finisar Corporation | Diagnostics for serial communication busses |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0042229A1 (en) * | 1980-06-16 | 1981-12-23 | The Post Office | Digital transmission systems |
EP0477699A2 (en) * | 1990-09-14 | 1992-04-01 | Fujitsu Limited | Optical communication system |
GB2254746A (en) * | 1991-04-12 | 1992-10-14 | Northern Telecom Europ Ltd | Optical transmitter |
US5504609A (en) * | 1995-05-11 | 1996-04-02 | Ciena Corporation | WDM optical communication system with remodulators |
Family Cites Families (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0102815B1 (en) * | 1982-09-02 | 1989-04-26 | BRITISH TELECOMMUNICATIONS public limited company | Optical communication |
JPH06224882A (en) * | 1992-10-03 | 1994-08-12 | Canon Inc | Optical fsk receiver and optical fdm-fsk transmission system using the same |
DE69434078T2 (en) * | 1993-03-11 | 2005-11-03 | At & T Corp. | Optical network with remote terminal query and optical network unit that transforms wavelengths |
DE4333405A1 (en) * | 1993-09-30 | 1995-04-06 | Siemens Ag | Method for re-adjusting a frequency or phase modulation shift of frequency or phase-modulated transmitted light |
US5483372A (en) * | 1994-11-29 | 1996-01-09 | International Business Machines Corporation | Single and multichannel transmission over long distances using repeated level-crossing remodulation |
US5726784A (en) * | 1995-05-11 | 1998-03-10 | Ciena Corp. | WDM optical communication system with remodulators and diverse optical transmitters |
US5784184A (en) * | 1995-05-11 | 1998-07-21 | Ciena Corporation | WDM Optical communication systems with remodulators and remodulating channel selectors |
US5594384A (en) * | 1995-07-13 | 1997-01-14 | Gnuco Technology Corporation | Enhanced peak detector |
US5625327A (en) * | 1995-07-13 | 1997-04-29 | Gnuco Technology Corporation | Modified Colpitts oscillator for driving an antenna coil and generating a clock signal |
US5960040A (en) * | 1996-12-05 | 1999-09-28 | Raytheon Company | Communication signal processors and methods |
US6101011A (en) * | 1997-05-29 | 2000-08-08 | Ciena Corporation | Modulation format adjusting optical transponders |
-
1997
- 1997-05-29 US US08/862,930 patent/US6101011A/en not_active Expired - Lifetime
-
1998
- 1998-05-29 DE DE69831941T patent/DE69831941T2/en not_active Expired - Fee Related
- 1998-05-29 CA CA002291610A patent/CA2291610A1/en not_active Abandoned
- 1998-05-29 WO PCT/US1998/009932 patent/WO1998054854A1/en active IP Right Grant
- 1998-05-29 EP EP98924772A patent/EP0981869B1/en not_active Expired - Lifetime
- 1998-05-29 AU AU76862/98A patent/AU7686298A/en not_active Abandoned
-
2000
- 2000-03-06 US US09/519,828 patent/US6256127B1/en not_active Expired - Lifetime
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0042229A1 (en) * | 1980-06-16 | 1981-12-23 | The Post Office | Digital transmission systems |
EP0477699A2 (en) * | 1990-09-14 | 1992-04-01 | Fujitsu Limited | Optical communication system |
GB2254746A (en) * | 1991-04-12 | 1992-10-14 | Northern Telecom Europ Ltd | Optical transmitter |
US5504609A (en) * | 1995-05-11 | 1996-04-02 | Ciena Corporation | WDM optical communication system with remodulators |
Non-Patent Citations (1)
Title |
---|
KIKUSHIMA ET AL: "SUPER-WIDE-BAND OPTICAL FM MODULATION SCHEME AND ITS APPLICATION TO MULTICHANNEL AM VIDEO TRANSMISSION SYSTEMS", IEEE PHOTONICS LETTERS, vol. 8, no. 6, June 1996 (1996-06-01), pages 839 - 841, XP002080940 * |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2013091706A1 (en) * | 2011-12-22 | 2013-06-27 | Telefonaktiebolaget L M Ericsson (Publ) | Muxponder and method of converting a plurality of tributary optical communications signals having a first bit rate into an optical line signal having a second, higher bit rate |
US9490931B2 (en) | 2011-12-22 | 2016-11-08 | Telefonaktiebolaget Lm Ericsson (Publ) | Muxponder and method of converting a plurality of tributary optical communications signals having a first bit rate into an optical line signal having a second, higher bit rate |
Also Published As
Publication number | Publication date |
---|---|
EP0981869A1 (en) | 2000-03-01 |
US6256127B1 (en) | 2001-07-03 |
EP0981869B1 (en) | 2005-10-19 |
US6101011A (en) | 2000-08-08 |
AU7686298A (en) | 1998-12-30 |
CA2291610A1 (en) | 1998-12-03 |
DE69831941D1 (en) | 2005-11-24 |
DE69831941T2 (en) | 2006-05-24 |
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