Alloptical gaincontrolled lumped Raman fibre amplifier - PowerPoint PPT Presentation

1 / 17
About This Presentation
Title:

Alloptical gaincontrolled lumped Raman fibre amplifier

Description:

Vg(?), (?) and ?(?) is the frequency dependent group velocity, fiber background ... Different degree. of clamping. All-optical gain-controlled lumped Raman ... – PowerPoint PPT presentation

Number of Views:64
Avg rating:3.0/5.0
Slides: 18
Provided by: janr6
Category:

less

Transcript and Presenter's Notes

Title: Alloptical gaincontrolled lumped Raman fibre amplifier


1
All-optical gain-controlled lumped Raman fibre
amplifier
  • Miroslav Karásek
  • Jirí Kanka
  • Pavel Honzátko
  • Jan Radil

2
All-optical gain-controlled lumped Raman fibre
amplifierOutline
  • Transient effects in Raman fibre amplifiers
  • Numerical simulations
  • Experimental verification
  • Conclusions

3
All-optical gain-controlled lumped Raman fibre
amplifier Transient effects in Raman fibre
amplifiers
  • Optical amplifiers saturate on the total power
    basis
  • Channel addition/removal or transmission of
    packets in burst mode would result in output
    power fluctuations in other channels
  • Some measurements must be taken to eliminate
    unwanted output power fluctuations
  • Several schemes has been suggested for gain
    stabilization of EDFAs
  • For lumped Raman fibre amplifiers, the
    all-optical gain-clamping technique can be used

4
All-optical gain-controlled lumped Raman fibre
amplifierNumerical simulations
  • Propagation of signals, pumps and spectral
    components of amplified spontaneous emission
    (ASE) is described by the following partial
    differential equation

5
All-optical gain-controlled lumped Raman fibre
amplifierNumerical simulations
  • The above equation represents a set of partial
    differential equations for down-stream and
    up-stream propagating optical powers P(z,t,?),
    P-(z,t,?) contained in frequency slot ?? and
    describe their evolution in space (along the
    fibre axis), z and time t
  • P(z,t,?), P-(z,t,?) represent the down-stream
    signals Ps(z,t,?s), up-stream pumps P-p (z,t,?p)
    and down-stream and up-stream ASE spectral
    components P?ASE(z,t,?)
  • Vg(?), ?(?) and ?(?) is the frequency dependent
    group velocity, fiber background loss, and the
    Rayleigh back scattering coefficient
  • gR(?-?) is the Raman gain coefficient between
    waves with frequency ? and ?, Keff and Aeff

6

All-optical gain-controlled lumped Raman fibre
amplifierNumerical simulations
Schematic diagram for numerical simulations.
Boundary conditions for signals, pumps, and ASE
components
7
All-optical gain-controlled lumped Raman fibre
amplifierNumerical simulations
Simulation data DCF - OFS EWBDK1360 L16km, D
-1260ps/nm Pp0(1445nm)800mW 8 WDM channels
starting at 1543nm 1nm spacing, Ps0
-12dBm/channel
Net gain at 1543nm as a function of input power
8
All-optical gain-controlled lumped Raman fibre
amplifierNumerical simulations
Output power variation at 1543nm Unclamped
regime
9
All-optical gain-controlled lumped Raman fibre
amplifierNumerical simulations
Output power variation at 1543nm clamped regime
10
All-optical gain-controlled lumped Raman fibre
amplifierNumerical simulations
Time evolution of lasing power at 1551nm
11
All-optical gain-controlled lumped Raman fibre
amplifierNumerical simulations
Different degree of clamping
12
All-optical gain-controlled lumped Raman fibre
amplifierExperiment
Experimental set-up
13
All-optical gain-controlled lumped Raman fibre
amplifierExperiment
Spectral dependence of net gain
14
All-optical gain-controlled lumped Raman fibre
amplifierExperiment
Net gain at 1538nm as a function of input power
15
All-optical gain-controlled lumped Raman fibre
amplifierExperiment
Output power fluctuation at 1540nm with and
without AOGC
16
All-optical gain-controlled lumped Raman fibre
amplifierConclusions
  • Surviving channel power fluctuations in lumped
    RFA have been investigated both theoretically and
    experimentally
  • It has been shown, that when sufficient lasing is
    allowed, steady-state surviving channel power
    fluctuations may be completely eliminated
  • Remaining power surges are about 8 times lower
    than the steady-state power excursions without
    AOGC

17
All-optical gain-controlled lumped Raman fibre
amplifier
  • Thank you for your attention!
Write a Comment
User Comments (0)
About PowerShow.com