公开(公告)号：CA2315989C

公开(公告)日：2004-10-05

申请号：CA2315989

申请日：2000-08-14

Applicant: LUCENT TECHNOLOGIES INC

Inventor： HUNZIKER GUIDO HERMANN ,  FEULNER MATTHIAS RICHARD ,  ZHOU JIANHUI ,  WERNER DIETER ,  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 fe ed- 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 detecte d. 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：DE60001444T2

公开(公告)日：2003-11-20

申请号：DE60001444

申请日：2000-09-11

Applicant: LUCENT TECHNOLOGIES INC

Inventor： DENKIN NATHAN MYRON ,  FEULNER MATTHIAS RICHARD ,  MA JIONG ,  WERNER DIETER ,  ZHU MING JUAN

IPC: H01S3/10 ,  H01S3/06 ,  H04B10/02 ,  H04B10/17 ,  H04B10/18 ,  H04B10/29 ,  H04J14/00 ,  H04J14/02

Abstract: An apparatus and method are described for controlling response to power transients in an optically amplified wavelength division multiplexed (WDM) network when WDM optical channels are added and dropped, during network reconfigurations, during failure events, and so on. In one embodiment, a variable bandwidth filter circuit operates at a first prescribed bandwidth during a first time period tau 0 to detect a change in signal power (i.e., power transient) caused by a transient event, and operates at a second prescribed bandwidth that is less than the first prescribed bandwidth after the first period of time elapses, e.g., tau 0 + INCREMENT tau , to substantially suppress low level signal variations, such as remnants of the power transient. In this way, the power transient related to the actual transient event will be preserved to trigger control circuitry, e.g., amplifier gain control based on input power changes, while the remnants will be filtered out to prevent unwanted responses by the control circuitry, e.g., remnants misinterpreted as actual transient events.