WO2005025094A1 - 光送信器 - Google Patents
光送信器 Download PDFInfo
- Publication number
- WO2005025094A1 WO2005025094A1 PCT/JP2003/010856 JP0310856W WO2005025094A1 WO 2005025094 A1 WO2005025094 A1 WO 2005025094A1 JP 0310856 W JP0310856 W JP 0310856W WO 2005025094 A1 WO2005025094 A1 WO 2005025094A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- signal
- differential
- phase
- optical
- output
- Prior art date
Links
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
- H04B10/50—Transmitters
- H04B10/501—Structural aspects
- H04B10/503—Laser transmitters
- H04B10/505—Laser transmitters using external modulation
-
- 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
- H04B10/50—Transmitters
- H04B10/501—Structural aspects
- H04B10/503—Laser transmitters
- H04B10/505—Laser transmitters using external modulation
- H04B10/5055—Laser transmitters using external modulation using a pre-coder
-
- 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
- H04B10/50—Transmitters
- H04B10/508—Pulse generation, e.g. generation of solitons
-
- 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
- H04B10/50—Transmitters
- H04B10/516—Details of coding or modulation
- H04B10/5162—Return-to-zero modulation schemes
-
- 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
- H04B10/50—Transmitters
- H04B10/516—Details of coding or modulation
- H04B10/548—Phase or frequency modulation
- H04B10/556—Digital modulation, e.g. differential phase shift keying [DPSK] or frequency shift keying [FSK]
- H04B10/5561—Digital phase modulation
Definitions
- the present invention relates to an optical transmitter applied to an optical transmission system using an optical fiber as a communication line.
- EDF E Electronic Doubled Fiber Amplifier
- the transmission speed per channel must be increased and the effective use of the amplification band (wavelength multiplexing interval) Narrowing) and extension of the relay interval have been required.
- DPSK differential phase shift keying modulation method
- DPSK Di I rerential Ph.D.
- DPSK Di I rerential Ph.D.
- a phase change between information data sequences generated from on / off binary signals is differentially encoded, and DC light is phase-modulated. For example, if there is no phase change between data (ie, the phase change is "0"), the "ON" signal If there is a phase change between the pulses (that is, the phase change is “ ⁇ ”), a differential sign signal is generated as an “off” signal.
- a signal obtained by performing (0, ⁇ ) phase modulation based on the “on” and “off” of the differentially coded signal using a phase modulator is referred to as an NRZ (No n-Re tur n-t). oZ ero) —DPSK modulation method. '
- the transmitting end converts a phase change between information data sequences generated from a binary signal of “on” or “off” into a differential code signal obtained by performing a differential code.
- Phase modulation of continuous (CW) light is a phase change between information data sequences generated from a binary signal of “on” or “off” into a differential code signal obtained by performing a differential code.
- the receiving end generates a differentially encoded signal from the DPSK signal, and decodes the original data signal from the differentially encoded signal. More specifically, at the receiving end, a self-delay interference detector equipped with a 1-bit delay interferometer, two photodetectors, a discriminator, etc. extracts a data signal by signal processing called self-delay detection. .
- this self-delay interference detector two photodetectors are switched and processed according to the phase of the interference result in the one-bit delay interferometer. Specifically, when the phase difference of the detection signal detected by the 1-bit delay interferometer is “0”, the detection signal is processed by one of the photodetectors, and when the phase difference is “ ⁇ ”, the other photodetector is processed. Processes the detection signal. Furthermore, the signal processed by either one of the photodetectors is used as an inverted output, and the detection signals of both are input to the subsequent classifier to extract the data signal. That is, in this detector, processing is performed by different photodetectors according to the phase of the interference result. Therefore, it has the feature that it can obtain twice the receiving sensitivity as compared with the conventional modulation method, on / off keying modulation (binary amplitude modulation).
- the DPSK modulation method which provides twice the receiving sensitivity compared to the on-off keying modulation method used in conventional optical transmission systems, has the potential to realize long-distance transmission in high-speed optical communication. Modulation method.
- the DPSK modulation method includes the NRZ—DPSK modulation method and the NRZ (1)
- an optical transmission device that further converts the DSPK signal into an RZ (Return-Zero) signal by performing intensity modulation, and performs signal transmission using the RZ-DPSK signal.
- Patent Document 1 states that, in a linear repeater system in which a 1.3 um zero-dispersion fiber transmission line is dispersion-compensated for each repeater section, the RZ signal has a regenerative repeater distance approximately three times larger than the NRZ signal at 40 Gbit / s It is predicted by simulation that the degree of expansion can be increased.
- Patent Document 1 experimentally shows that in a 10_Gbit / s, 8-wavelength WDM transmission system, the power per channel of an RZ signal can be increased as compared with an NRZ signal. It is clear that what is described in Non-Patent Document 2 is described.
- Non-Patent Document 3 reports that long-distance transmission of 5200 km was achieved using the RZ_DP SK modulation scheme.
- Patent Document 1
- Patent Document 2
- Patent Document 1 discloses that the bandwidth required for the electric circuit is 2 compared to the case where the NRZ electric signal is handled in the electric domain. He pointed out that it was necessary to double the speed and it was difficult to increase the speed.
- generating an RZ signal in the electrical domain means that the circuit size of the optical transmitter itself can be reduced, and that the stability of equipment and the advantages of cost can be used. Advantages.
- the electric N An RZ-DPSK signal is generated by phase-modulating the RZ-DP SK signal with an optical phase modulator and intensity-modulating the phase-modulated signal with an optical intensity modulator.
- an extra circuit in this case, an optical phase modulator
- I do I do.
- Patent Document 1 in the conventional method of amplifying an RZ electric signal as it is, when a capacitive coupling type driving circuit is used, a DC level fluctuation of a driving waveform occurs due to a fluctuation in a mark ratio of a signal, and an output dynamic range of the driving circuit is generated. It is pointed out that the control circuit must be approximately twice or more, and a control circuit that compensates for the bias point of the optical intensity modulator that fluctuates according to the mark ratio by the mark ratio is required.
- the present invention has been made in view of the above circumstances, and an optical transmitter for performing optical transmission using an optical RZ-DPSK signal performs optical modulation using an electric RZ-DP SK signal.
- the purpose of the present invention is to provide an optical transmitter with reduced circuit scale and excellent equipment stability and cost. Disclosure of the invention
- An optical transmitter includes a differential encoder that generates a differentially encoded signal based on a data signal, and a differential encoder that generates a differentially encoded signal based on the differentially encoded signal output from the differential encoder.
- An RZ encoder that generates an electric RZ differential signal that is an RZ (Return to Zero) signal in the electric domain; and an optical RZ—DP SK (D) that is an RZ signal in the optical domain based on the electric RZ differential signal.
- Aro ifferentia 1 Phase Shutter Keying Mach-Zehnder interferometer-type intensity modulator that generates a signal.
- a differentially encoded signal based on the data signal is generated by the differential encoder, and is an RZ (Return to Zero) signal in the electric domain based on the differentially encoded signal.
- An electric RZ differential signal is generated by an RZ encoder, and based on the electric RZ differential signal, an optical RZ—DP SK (Differential Phase Shift Ke ying) signal, which is an RZ signal in the optical domain, is generated.
- an optical RZ—DP SK Different Phase Shift Ke ying
- FIG. 1 is a block diagram illustrating a configuration of an optical transmitter according to an embodiment of the present invention.
- FIG. 2 is a configuration example of a Mach-Zehnder interferometric optical modulator of the optical transmitter illustrated in FIG.
- FIG. 3 is a block diagram showing a detailed configuration of a main part of the optical transmitter shown in FIG. 1, and
- FIG. 4 is a modulation / demodulation process of an RZ-DP SK signal according to the present invention.
- FIG. 5 is an explanatory diagram showing a process of generating an optical RZ-DPSK signal from two RZ differential signals.
- FIG. 1 is a block diagram showing a configuration of an optical transmitter according to an embodiment of the present invention.
- the optical transmitter shown in FIG. 1 includes a light source 1, a Matsuhatsu-Donda interferometer type intensity modulator 2, a differential encoder 3, and an RZ encoder 4.
- An optical fiber line 6 is connected to the Matsuha Gender interferometer type intensity modulator 2 of the optical transmitter.
- a differential encoding device 3 uses an input data signal of f [Gbit / s] to generate two differential signals (a positive-phase signal D and a negative-phase signal E (D Generates an inverted signal)) and outputs it to the RZ encoder 4.
- the RZ encoder 4 has two AND circuits, and one of the AND circuits receives the positive-phase signal D output from the differential encoder 3 and the clock signal, and the other AND circuit The circuit receives the inverted-phase signal E output from the differential encoder 3 and the clock signal.
- FIG. 2 is a schematic diagram showing a configuration example of a Matsuhatsu-Donda interferometric optical modulator among the optical transmitters shown in FIG.
- a Mach-Zehnder interferometer-type optical modulator is used as an optical intensity modulator, but the Mach-Zehnder interferometer-type intensity modulator 2 of the present invention comprises an interferometer as shown in FIG. That can independently modulate (control) the phase of each optical path By using this, it is possible to function as a light intensity modulator capable of performing a differential operation.
- the data input terminals 17 and the inverted data input terminal 18 receive two binary data signals whose phases are inverted from each other.
- the peak-to-peak voltage of each signal is the same as that of the Mach-Zehnder interferometer type intensity modulator 2. What is necessary is just to set to a half wavelength voltage.
- FIG. 3 is a block diagram showing a detailed configuration of a main part of the optical transmitter shown in FIG. 1, and FIG. 4 is a timing chart for explaining modulation / demodulation processing of an RZ-DPSK signal according to the present invention. It is.
- the states at the respective portions of the alphabet symbols A to H shown in the diagram of FIG. 3 correspond to the waveforms indicated by the alphabet symbols A to H of FIG. 4, respectively.
- the differential encoder 3 includes a 1-bit delay circuit 31, an exclusive OR circuit 32, and a differential circuit 33
- the RZ encoder 4 includes AND circuits 4 1, 4 It has two.
- an output of an exclusive OR circuit 32 (hereinafter, referred to as “O”) to which a data signal (A) and an output from a 1-bit delay circuit (hereinafter, referred to as “delay circuit output”) (B) are inputted.
- (C) is input to the differential circuit 33.
- the output of the positive-phase differential signal (D), which is the inverted output of the differential circuit 33, is input to the AND circuit 41 of the RZ encoder 4 and also to the 1-bit delay circuit 31.
- the negative-phase differential signal (E) which is the non-inverted output of the differential circuit 33, is input to the AND circuit 41 of the RZ encoder 4.
- the inverted output of the differential circuit 33 is referred to as a positive-phase differential signal
- the non-inverted output is referred to as a negative-phase differential signal, for convenience.
- the interpretation of the "1" level or "0" level in the electrical domain and the interpretation of the "1" level or "0” level in the optical domain can be realized in a mutually consistent manner. Then, the positive and negative phases of the differential signal may be determined.
- the positive-phase differential signal (D) and negative-phase differential signal (E) output from the differential circuit 33 are input to the logical AND circuits 41 and 42, respectively, and synchronized with the clock signal input.
- the positive-phase RZ differential signal (F) and the negative-phase RZ differential signal (G ) Is output to the Matsuhatsu-Donda interferometer type intensity modulator 2.
- the Matsuhatsunda interferometer-type intensity modulator 2 generates an optical RZ-DPSK signal using the positive-phase RZ differential signal (F) and the negative-phase RZ differential signal (G).
- the input data signal (A) is, for example, a bit string of “00000100 01 10”.
- the initial state of the exclusive OR circuit output (C) is 0, the first bit of the 1-bit delay circuit output (B) is at the "1" level.
- the exclusive OR circuit output (C) becomes the output of the exclusive OR of the data signal (A) and the delay circuit output (B), and is at the “1” level.
- the positive-phase differential signal (D) is at the "0" level, which is the opposite phase to the exclusive-OR circuit output (C), while the negative-phase differential signal (E) is the exclusive-OR circuit output.
- "1" is the same phase as (C).
- the positive-phase differential signal (D) and the negative-phase differential signal (E) are input to AND circuits 41 and 42, respectively, and the positive-phase RZ differential signal (F) and the negative-phase RZ differential synchronized with the clock signal are inputted.
- Each signal (G) is generated.
- An optical RZ-DPSK signal (H) is generated based on the positive-phase RZ differential signal (F) and the negative-phase RZ differential signal (G).
- the optical RZ-DPSK signal (H) is a continuous pulse train of light intensity, but is modulated by the negative-phase RZ differential signal (G) and the positive-phase RZ differential signal (F). In this case, the relative phase is modulated at 0 and ⁇ , respectively.
- the original data signal can be obtained by intensity-modulating the phase difference between adjacent bits, as in a general optical DPSK signal. .
- FIG. 5 is an explanatory diagram showing a process of generating an optical RZ-DPSK signal from two RZ differential signals.
- the Mach-Zehnder interferometer type The DC bias point is used as the valley (extinction point) of the transmission characteristics for the light transmission characteristics of modulator 2, and two RZ differential signals (positive-phase RZ differential signals) are applied to two electrodes (electrode 1 and electrode 2). And negative-phase RZ differential signal).
- the light intensity is a continuous pulse train, but since the relative phase changes by ⁇ at the valley of the transmission characteristics, the relative phase is modulated to 0 / ⁇ by applying two R ⁇ differential signals.
- a differentially coded signal based on the data signal is generated by the differential coder, and the differentially coded signal is generated based on the differentially coded signal.
- An electrical RZ differential signal which is an RZ (Return to Zero) signal in the electrical domain, is generated by an RZ encoder, and based on the electrical RZ differential signal, an optical RZ signal, which is an RZ signal in the optical domain, is generated.
- the DP SK (Differentia 1 Phase Shift Keying) signal is generated by the Mach-Zehnder interferometer-type intensity modulator (2), the circuit scale can be reduced, the equipment stability can be increased, or Has an effect that it can contribute to cost reduction.
- a positive-phase differential signal which is an inverted output of an exclusive-OR output of a delayed output obtained by delaying its own output by one bit and a data signal, and an exclusive-OR output
- An electrical RZ-DP SK signal in the electrical domain is generated by using the negative-phase differential signal that is the non-inverted output of the positive-phase RZ differential that is output in synchronization with the clock signal.
- RZ differential signal in the electrical domain consisting of two signals: a signal and a negative-phase RZ differential signal that is output in synchronization with the clock signal.
- the present invention is useful for an optical transmitter constituting an optical transmission system using an optical fiber as a communication line.
Landscapes
- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Optics & Photonics (AREA)
- Optical Communication System (AREA)
- Optical Modulation, Optical Deflection, Nonlinear Optics, Optical Demodulation, Optical Logic Elements (AREA)
- Digital Transmission Methods That Use Modulated Carrier Waves (AREA)
Abstract
Description
Claims
Priority Applications (5)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2005508732A JP4554519B2 (ja) | 2003-08-27 | 2003-08-27 | 光送信器 |
US10/562,147 US7809281B2 (en) | 2003-08-27 | 2003-08-27 | Optical transmitter |
PCT/JP2003/010856 WO2005025094A1 (ja) | 2003-08-27 | 2003-08-27 | 光送信器 |
DE60322977T DE60322977D1 (de) | 2003-08-27 | 2003-08-27 | Optischer sender |
EP03818524A EP1659710B1 (en) | 2003-08-27 | 2003-08-27 | Optical transmitter |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
PCT/JP2003/010856 WO2005025094A1 (ja) | 2003-08-27 | 2003-08-27 | 光送信器 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2005025094A1 true WO2005025094A1 (ja) | 2005-03-17 |
Family
ID=34260069
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/JP2003/010856 WO2005025094A1 (ja) | 2003-08-27 | 2003-08-27 | 光送信器 |
Country Status (5)
Country | Link |
---|---|
US (1) | US7809281B2 (ja) |
EP (1) | EP1659710B1 (ja) |
JP (1) | JP4554519B2 (ja) |
DE (1) | DE60322977D1 (ja) |
WO (1) | WO2005025094A1 (ja) |
Cited By (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2006020324A (ja) * | 2004-06-30 | 2006-01-19 | Lucent Technol Inc | Crz−dpsk光信号発生のための方法と装置 |
JP2006251570A (ja) * | 2005-03-11 | 2006-09-21 | Nec Corp | 光送信器及び位相変調方法 |
JP2006345416A (ja) * | 2005-06-10 | 2006-12-21 | Nec Corp | 光送信システムおよび光送信方法 |
US7501914B2 (en) | 2004-04-28 | 2009-03-10 | Mitsubishi Electric Corporation | Bias circuit |
US7885550B2 (en) | 2003-11-27 | 2011-02-08 | Xtera Communications Ltd. | Method and apparatus for producing RZ-DPSK modulated optical signals |
JP2011040881A (ja) * | 2009-08-07 | 2011-02-24 | Hitachi Ltd | 光送信器 |
US8295715B2 (en) | 2008-04-14 | 2012-10-23 | Fujitsu Limited | Optical receiver and optical phase control method thereof |
Families Citing this family (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE10329459A1 (de) * | 2003-07-01 | 2005-01-20 | Marconi Communications Gmbh | Sender für ein optisches Nachrichtensignal |
KR100584433B1 (ko) * | 2003-11-25 | 2006-05-26 | 삼성전자주식회사 | 차등 편광 변조 방식의 광전송 시스템 |
US7466926B2 (en) * | 2004-05-28 | 2008-12-16 | Alcatel-Lucent Usa Inc. | Method and apparatus for RZ-DPSK optical signal generation |
US7447386B2 (en) * | 2006-02-23 | 2008-11-04 | Magiq Technologies, Inc | Cascaded modulator system and method for QKD |
US8204386B2 (en) * | 2007-04-06 | 2012-06-19 | Finisar Corporation | Chirped laser with passive filter element for differential phase shift keying generation |
CN101150370A (zh) * | 2007-04-12 | 2008-03-26 | 中兴通讯股份有限公司 | Rz-dpsk调制光信号产生装置及方法 |
JP5264521B2 (ja) * | 2009-01-16 | 2013-08-14 | 三菱電機株式会社 | 光送信器 |
JP2011022479A (ja) * | 2009-07-17 | 2011-02-03 | Mitsubishi Electric Corp | 多値光送信器 |
US8325410B2 (en) * | 2009-08-19 | 2012-12-04 | Jds Uniphase Corporation | Modulation system and method for generating a return-to-zero (RZ) optical data signal |
US9252889B2 (en) * | 2011-11-03 | 2016-02-02 | Mellanox Technologies Denmark Aps | Fast optical receiver |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2000106543A (ja) * | 1998-07-29 | 2000-04-11 | Nippon Telegr & Teleph Corp <Ntt> | 光伝送装置 |
JP2000156665A (ja) * | 1998-11-19 | 2000-06-06 | Nippon Telegr & Teleph Corp <Ntt> | 光伝送方法、光送信装置および光伝送システム |
JP2001147411A (ja) * | 1999-09-27 | 2001-05-29 | Alcatel | 光変調器 |
Family Cites Families (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5543952A (en) * | 1994-09-12 | 1996-08-06 | Nippon Telegraph And Telephone Corporation | Optical transmission system |
DE69940873D1 (de) * | 1998-07-29 | 2009-06-25 | Nippon Telegraph & Telephone | Optisches Übertragungssystem |
US6535316B1 (en) * | 1999-08-13 | 2003-03-18 | Lucent Technologies Inc. | Generation of high-speed digital optical signals |
EP1128580B1 (en) * | 2000-02-28 | 2010-08-18 | Nippon Telegraph And Telephone Corporation | Optical transmission method, optical transmitter and optical receiver |
JP3625726B2 (ja) | 2000-03-06 | 2005-03-02 | 日本電信電話株式会社 | 光伝送装置および光伝送システム |
US20030156774A1 (en) * | 2002-02-15 | 2003-08-21 | Jan Conradi | Unipolar electrical to bipolar optical converter |
JP3975810B2 (ja) * | 2002-04-05 | 2007-09-12 | 株式会社日立製作所 | 光片側サイドバンド送信器 |
WO2003092237A1 (en) * | 2002-04-23 | 2003-11-06 | Quellan, Inc. | Combined ask/dpsk modulation system |
GB0327605D0 (en) * | 2003-11-27 | 2003-12-31 | Azea Networks Ltd | Method and apparatus for producing chirped RZ-DPSK modulated optical signals |
-
2003
- 2003-08-27 US US10/562,147 patent/US7809281B2/en active Active - Reinstated
- 2003-08-27 EP EP03818524A patent/EP1659710B1/en not_active Expired - Fee Related
- 2003-08-27 JP JP2005508732A patent/JP4554519B2/ja not_active Expired - Fee Related
- 2003-08-27 WO PCT/JP2003/010856 patent/WO2005025094A1/ja active IP Right Grant
- 2003-08-27 DE DE60322977T patent/DE60322977D1/de not_active Expired - Lifetime
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2000106543A (ja) * | 1998-07-29 | 2000-04-11 | Nippon Telegr & Teleph Corp <Ntt> | 光伝送装置 |
JP2000156665A (ja) * | 1998-11-19 | 2000-06-06 | Nippon Telegr & Teleph Corp <Ntt> | 光伝送方法、光送信装置および光伝送システム |
JP2001147411A (ja) * | 1999-09-27 | 2001-05-29 | Alcatel | 光変調器 |
Non-Patent Citations (1)
Title |
---|
See also references of EP1659710A4 * |
Cited By (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US7885550B2 (en) | 2003-11-27 | 2011-02-08 | Xtera Communications Ltd. | Method and apparatus for producing RZ-DPSK modulated optical signals |
US7501914B2 (en) | 2004-04-28 | 2009-03-10 | Mitsubishi Electric Corporation | Bias circuit |
JP2006020324A (ja) * | 2004-06-30 | 2006-01-19 | Lucent Technol Inc | Crz−dpsk光信号発生のための方法と装置 |
JP4668701B2 (ja) * | 2004-06-30 | 2011-04-13 | アルカテル−ルーセント ユーエスエー インコーポレーテッド | Crz−dpsk光信号発生のための方法と装置 |
JP2006251570A (ja) * | 2005-03-11 | 2006-09-21 | Nec Corp | 光送信器及び位相変調方法 |
JP2006345416A (ja) * | 2005-06-10 | 2006-12-21 | Nec Corp | 光送信システムおよび光送信方法 |
JP4687262B2 (ja) * | 2005-06-10 | 2011-05-25 | 日本電気株式会社 | 光送信システムおよび光送信方法 |
US8295715B2 (en) | 2008-04-14 | 2012-10-23 | Fujitsu Limited | Optical receiver and optical phase control method thereof |
JP2011040881A (ja) * | 2009-08-07 | 2011-02-24 | Hitachi Ltd | 光送信器 |
Also Published As
Publication number | Publication date |
---|---|
US7809281B2 (en) | 2010-10-05 |
JP4554519B2 (ja) | 2010-09-29 |
JPWO2005025094A1 (ja) | 2006-11-16 |
EP1659710A4 (en) | 2006-11-29 |
EP1659710B1 (en) | 2008-08-13 |
DE60322977D1 (de) | 2008-09-25 |
EP1659710A1 (en) | 2006-05-24 |
US20060245763A1 (en) | 2006-11-02 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
EP1612972B1 (en) | Method and apparatus for generating CRZ-DPSK optical signals | |
US7116917B2 (en) | Optical transmitter and optical transmission system | |
JP4558271B2 (ja) | 光通信の改良または光通信に関連した改良 | |
WO2005025094A1 (ja) | 光送信器 | |
EP1519500A1 (en) | System and method for optically labeled packet transmission | |
JP4695500B2 (ja) | 信号再生装置,光受信装置および信号処理方法 | |
JP4941852B1 (ja) | 疑似リターントゥゼロ変調のための装置 | |
US7277647B2 (en) | System and method of optical transmission | |
JP2008066849A (ja) | 光送信機およびその駆動方法 | |
WO2006085826A1 (en) | Optical msk data format | |
JP3371857B2 (ja) | 光伝送装置 | |
EP1601122A1 (en) | Method and apparatus for RZ-DPSK optical signal generation | |
US8687970B2 (en) | Modulator and demodulator for a differential optical modulation format with eight phase changes | |
US7280767B1 (en) | Half rate precoded data RZ transmitter | |
EP1411656A2 (en) | Optical duobinary carrier-suppressed RZ transmission system | |
JP2004312678A (ja) | デュオバイナリ光伝送装置 | |
JP2006251570A (ja) | 光送信器及び位相変調方法 | |
EP1716650B1 (en) | System for generating optical return-to-zero signals with alternating bi-phase shift | |
JP2004254242A (ja) | 光送信機および光送信装置 | |
JP4104999B2 (ja) | 光送信器、光受信器、光伝送システムおよび光伝送方法 | |
Shao et al. | Staggered differential phase-shift keying format with RZ or CSRZ clock for 100Gbit/s transmission |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AK | Designated states |
Kind code of ref document: A1 Designated state(s): JP US |
|
AL | Designated countries for regional patents |
Kind code of ref document: A1 Designated state(s): AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IT LU MC NL PT RO SE SI SK TR |
|
121 | Ep: the epo has been informed by wipo that ep was designated in this application | ||
WWE | Wipo information: entry into national phase |
Ref document number: 2005508732 Country of ref document: JP |
|
WWE | Wipo information: entry into national phase |
Ref document number: 2003818524 Country of ref document: EP |
|
WWE | Wipo information: entry into national phase |
Ref document number: 2006245763 Country of ref document: US Ref document number: 10562147 Country of ref document: US |
|
WWP | Wipo information: published in national office |
Ref document number: 2003818524 Country of ref document: EP |
|
WWP | Wipo information: published in national office |
Ref document number: 10562147 Country of ref document: US |
|
WWG | Wipo information: grant in national office |
Ref document number: 2003818524 Country of ref document: EP |