公开(公告)号：JP2001111151A

公开(公告)日：2001-04-20

申请号：JP2000249209

申请日：2000-08-21

Applicant: LUCENT TECHNOLOGIES INC

Inventor： FEULNER MATTHIAS RICHARD ,  HUNZIKER GUIDO HERMANN ,  TEICHMANN BERND ,  WERNER DIETER ,  ZHOU JIANHUI

IPC: H01S3/10 ,  H01S3/06 ,  H01S3/13 ,  H01S3/131 ,  H04B10/17 ,  H04B10/29 ,  H04J14/00 ,  H04J14/02

Abstract: PROBLEM TO BE SOLVED: To provide a device and its method for keeping constant relatively a gain per channel of an optical channel in an optical amplification WDM system even when an input intensity of an optical amplifier changes. SOLUTION: A gain of an optical amplifier is controlled by controlling a pumping intensity amount to be supplied to the optical amplifier as a function of a change of an optical input intensity to be measured in a feed forward monitoring route. The pumping intensity amount is adjusted according to a proportional relationship with respect to the measured input intensity. The pumping intensity is directly controlled, so that the gain of the optical amplifier is controlled in a time scale of less than microsecond from a detection of a change of the input intensity. Furthermore, a gain per channel in the amplified WDM signal is kept relatively constant irrespective of the change of the input intensity of the optical amplifier, thereby reducing substantially an intensity deflection in an optical channel in which the WDM signal is left behind.

公开(公告)号：JP2000089179A

公开(公告)日：2000-03-31

申请号：JP20552399

申请日：1999-07-21

Applicant: LUCENT TECHNOLOGIES INC

Inventor： DORSCHKY CLAUS ,  HAUNSTEIN HERBERT ,  TEICHMANN BERND

IPC: G02F1/01 ,  H04B10/50 ,  H04B10/508 ,  H04B10/516 ,  H04B10/04 ,  H04B10/06 ,  H04B10/142 ,  H04B10/152

Abstract: PROBLEM TO BE SOLVED: To enable the automatic phase matching of input signals when there is a temperature change or aging of component elements by analyzing a modulation PTZ signal generated for the purpose of phase deviation of one of the input signals and phase matching of the input signals, thereby subjecting the input signals to phase matching. SOLUTION: A signal generator 11 generates an auxiliary signal which is supplied to the input C of a voltage control oscillator 2. Next, the RTZ signal RZ is modulated by a modulator 4. The periodic phase deviations lower average output power. The output signal (O) of the modulator 4 is supplied to a coupler 5. The coupler 5 couples and outputs the light signal having part of the energy of the output signal (O). The light signal which is coupled and outputted is supplied to an optical converter 6 and is converted to an electric signal. The electric signal is coupled to a low-pass filter 7. This low-pass filter 7 allows the passage of only the low-frequency signal. Consequently, the generated signal is mixed with the auxiliary signal of the signal generator 11 by a multiplier 8 and the demodulation of the generated signal is induced.

公开(公告)号：DE60019212D1

公开(公告)日：2005-05-12

申请号：DE60019212

申请日：2000-08-14

Applicant: LUCENT TECHNOLOGIES INC

Inventor： FEULNER MATTHIAS RICHARD ,  HUNZIKER GUIDO HERMANN ,  TEICHMANN BERND ,  WERNER DIETER ,  ZHOU JIANHUI

IPC: H01S3/10 ,  H01S3/06 ,  H01S3/13 ,  H01S3/131 ,  H04B10/17 ,  H04B10/29 ,  H04J14/00 ,  H04J14/02 ,  H01S3/067 ,  H01Q1/24

Abstract: In an optically amplified wavelength division multiplexed (WDM) system having a WDM signal comprising a plurality of optical channels, the per-channel gain of the optical channels is kept relatively constant despite changes in input power at the optical amplifier (101), such as when individual optical channels of the WDM signal are added and dropped. More specifically, gain of an optical amplifier (101) is controlled by controlling the amount of pump power (110) supplied to the optical amplifier as a function of changes in input power which are measured in a feed-forward monitoring path (130, 140). The amount of pump power for effecting gain control is adjusted according to a scaled relationship to the measured input power of the optical amplifier. By controlling the pump power (by 120) directly in response to changes in input power, gain of the optical amplifier can be controlled within a sub-microsecond time scale from the time that a change in input power is detected. Moreover, by maintaining relatively constant per-channel gain in an amplified WDM signal despite changes in input power at the optical amplifier, power excursions are substantially reduced in surviving optical channels of the WDM signal, i.e., those at the output of the optical amplifier.

公开(公告)号：CA2254544C

公开(公告)日：2002-04-16

申请号：CA2254544

申请日：1998-11-26

Applicant: LUCENT TECHNOLOGIES INC

Inventor： TEICHMANN BERND ,  BODE DIRK ,  ZHOU JIANHUI

IPC: H04J14/00 ,  H04B10/07 ,  H04B10/29 ,  H04B10/294 ,  H04J14/02 ,  H04B10/17

Abstract: The present invention relates generally to the field of optical transmission and particularly to a method and a system for controlling optical amplification in wavelength division multiplex optical transmission. WDM systems currently under development will have eighty or more channels, i.e. modulated optical signal s with different wavelengths (known as Dense Wavelength Division Multiplexing, DWDM). These DWDM systems are demanding optical amplifiers which, especially considering the cascadation of a plurality of optical amplifiers along the transmission path of the DWDM system, have only very limited tolerances in certain parameters. Among these parameters gain flatness and gain tilt are o f special importance. The present invention discloses a method and a system which make use of auxiliary optical signals having a given power level which is equal for all auxiliary signals. Differences in the power levels of the auxiliary signals after optical amplification are used for the control of the optical amplifiers of the WDM system.

公开(公告)号：DE69838127D1

公开(公告)日：2007-09-06

申请号：DE69838127

申请日：1998-01-27

Applicant: LUCENT TECHNOLOGIES INC

Inventor： BODE DIRK ,  ZHOU JIANHUI ,  TEICHMANN BERND

IPC: H04J14/00 ,  H04J14/02 ,  H04B10/07 ,  H04B10/29 ,  H04B10/294

Abstract: The present invention relates generally to the field of optical transmission and particularly to a method and a system for controlling optical amplification in wavelength division multiplex optical transmission. WDM systems currently under development will have eighty or more channels, i. e. modulated optical signals with different wavelengths (known as Dense Wavelength Division Multiplexing, DWDM). These DWDM systems are demanding optical amplifiers which, especially considering the cascadation of a plurality of optical amplifiers along the transmission path of the DWDM system, have only very limited tolerances in certain parameters. Among these parameters gain flatness and gain tilt are of special importance. The present invention discloses a method and a system which make use of auxiliary optical signals having a given power level which is equal for all auxiliary signals. Differences in the power levels of the auxiliary signals after optical amplification are used for the control of the optical amplifiers of the WDM system.

公开(公告)号：CA2254544A1

公开(公告)日：1999-07-27

申请号：CA2254544

申请日：1998-11-26

Applicant: LUCENT TECHNOLOGIES INC

Inventor： TEICHMANN BERND ,  ZHOU JIANHUI ,  BODE DIRK

IPC: H04J14/00 ,  H04B10/07 ,  H04B10/29 ,  H04B10/294 ,  H04J14/02 ,  H04B10/17

Abstract: The present invention relates generally to the field of optical transmission and particularly to a method and a system for controlling optical amplification in wavelength division multiplex optical transmission. WDM systems currently under development will have eighty or more channels i. e. modulated optical signals with different wavelengths (known as Dense Wavelength Division Multiplexing DWDM). These DWDM systems are demanding optical amplifiers which especially considering the cascadation of a plurality of optica l amplifiers along the transmission path of the DWDM system have only very limited tolerances in certain parameters. Among these parameters gain flatness and gain tilt are of special importance. The present invention discloses a method and a system which make use of auxiliar y optical signals having a given power level which is equal for all auxiliary sign als. Differences in the power levels of the auxiliary signals after optical amplifica tion are used for the control of the optical amplifiers of the WDM system.

公开(公告)号：DE69838127T2

公开(公告)日：2008-05-15

申请号：DE69838127

申请日：1998-01-27

Applicant: LUCENT TECHNOLOGIES INC

Inventor： BODE DIRK ,  ZHOU JIANHUI ,  TEICHMANN BERND

IPC: H04J14/00 ,  H04J14/02 ,  H04B10/07 ,  H04B10/29 ,  H04B10/294

Abstract: The present invention relates generally to the field of optical transmission and particularly to a method and a system for controlling optical amplification in wavelength division multiplex optical transmission. WDM systems currently under development will have eighty or more channels, i. e. modulated optical signals with different wavelengths (known as Dense Wavelength Division Multiplexing, DWDM). These DWDM systems are demanding optical amplifiers which, especially considering the cascadation of a plurality of optical amplifiers along the transmission path of the DWDM system, have only very limited tolerances in certain parameters. Among these parameters gain flatness and gain tilt are of special importance. The present invention discloses a method and a system which make use of auxiliary optical signals having a given power level which is equal for all auxiliary signals. Differences in the power levels of the auxiliary signals after optical amplification are used for the control of the optical amplifiers of the WDM system.

公开(公告)号：DE69801663D1

公开(公告)日：2001-10-18

申请号：DE69801663

申请日：1998-10-13

Applicant: LUCENT TECHNOLOGIES INC

Inventor： MOELLER LOTHAR BENEDICT ERHARD ,  TEICHMANN BERND

IPC: H04B10/564 ,  H04J14/00 ,  H04J14/02 ,  H04B10/152

Abstract: The present invention generally relates to the field of optical transmission and particularly to a method and an apparatus for controlling the optical power of an optical transmission signal in wavelength division multiplex optical transmission system (WDM system). It is known to add one additional channel to the optical transmission signal of WDM systems, for controlling the power of the optical transmission signal. The optical power of the control channel is controlled to keep the total optical power of the optical transmission signal constant, e. g., if a channel of the optical transmission signal fails, the optical power of the control channel is increased. After surpassing a certain power level the optical signal of the control channel is reflected form the optical fibre because of a non linear effect known as Stimulated Brillouin Scattering (BSS). The present invention avoids this disadvantage by spreading the power density spectrum of the optical control signal.

公开(公告)号：CA2315989A1

公开(公告)日：2001-02-25

申请号：CA2315989

申请日：2000-08-14

Applicant: LUCENT TECHNOLOGIES INC

Inventor： FEULNER MATTHIAS RICHARD ,  ZHOU JIANHUI ,  WERNER DIETER ,  HUNZIKER GUIDO HERMANN ,  TEICHMANN BERND

IPC: H01S3/10 ,  H01S3/06 ,  H01S3/13 ,  H01S3/131 ,  H04B10/17 ,  H04B10/29 ,  H04J14/00 ,  H04J14/02

Abstract: In an optically amplified wavelength division multiplexed (WDM) system having a WDM signal comprising a plurality of optical channels, the per- channel gain of the optical channels is kept relatively constant despite changes in input power at the optical amplifier, such as when individual optical channels of the WDM signal are added and dropped. More specifically, gain of an optical amplifier is controlled by controlling the amount of pump power supplied to the optica l amplifier as a function of changes in input power which are measured in a feed-forward monitoring path. The amount of pump power for effecting gain control is adjusted according to a scaled relationship to the measured input power of t he optical amplifier. By controlling the pump power directly in response to changes in input power, gain of the optical amplifier can be controlled within a sub- microsecond time scale from the time that a change in input power is detected. Moreover, by maintaining relatively constant per-channel gain in an amplifi ed WDM signal despite changes in input power at the optical amplifier, pow er excursions are substantially reduced in surviving optical channels of the WD M signal, i.e., those at the output of the optical amplifier.

公开(公告)号：DE60019212T2

公开(公告)日：2006-03-09

申请号：DE60019212

申请日：2000-08-14

Applicant: LUCENT TECHNOLOGIES INC

Inventor： FEULNER MATTHIAS RICHARD ,  HUNZIKER GUIDO HERMANN ,  TEICHMANN BERND ,  WERNER DIETER ,  ZHOU JIANHUI

IPC: H01S3/10 ,  H01Q1/24 ,  H01S3/06 ,  H01S3/067 ,  H01S3/13 ,  H01S3/131 ,  H04B10/17 ,  H04B10/29 ,  H04J14/00 ,  H04J14/02

Abstract: In an optically amplified wavelength division multiplexed (WDM) system having a WDM signal comprising a plurality of optical channels, the per-channel gain of the optical channels is kept relatively constant despite changes in input power at the optical amplifier (101), such as when individual optical channels of the WDM signal are added and dropped. More specifically, gain of an optical amplifier (101) is controlled by controlling the amount of pump power (110) supplied to the optical amplifier as a function of changes in input power which are measured in a feed-forward monitoring path (130, 140). The amount of pump power for effecting gain control is adjusted according to a scaled relationship to the measured input power of the optical amplifier. By controlling the pump power (by 120) directly in response to changes in input power, gain of the optical amplifier can be controlled within a sub-microsecond time scale from the time that a change in input power is detected. Moreover, by maintaining relatively constant per-channel gain in an amplified WDM signal despite changes in input power at the optical amplifier, power excursions are substantially reduced in surviving optical channels of the WDM signal, i.e., those at the output of the optical amplifier.