Electronic Dispersion Compensation Utilising Full Optical Field Estimation

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Electronic Dispersion Compensation Utilising Full
Optical Field Estimation
Mary McCarthy, Andrew D. Ellis Photonic
Systems Group, Tyndall Institute/Dept of
Physics, University College Cork, Ireland.
mary.mccarthy_at_tyndall.ie
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Outline

• Review of electronic dispersion compensation
  (EDC)
• Passive optical field detection
• Simulation results
• Conclusions

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Dispersion Compensation
Transmitter
Modulation formats
Predistortion techniques
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Principle of operation

• Imaging of optical signal in electrical domain
• Frequency sensitive filter
• Asymmetrical Mach-Zehnder interferometer
• Biased at Quadrature (approx. linear response wrt
  frequency)
• Total output is proportional to incident to
  amplitude

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Optical field detection reconstruction
Legend Received signal Upper photodiode Lower
photodiode Reconstructed signals
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Numerical simulations

• 4.5dB noise figure
• 20 dB span loss
• (fixed OSNR)
• 6 spans each of 0-100km

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Dispersion Compensation Results
EAM 0 km
EAM 600 km
EAM 600 km compensated
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Practical implementations

• Modelling implementation limitations
• Amplifier saturation
• Removing division
• Implementing continuously tuneable dispersive
  transmission line?
• Wavelength dependency?

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Conclusions

• Proposed and simulated novel technique for
• DCF free transmission
• At least 600km _at_ 10.7 Gbit/s
• Suitable for Metro Networks
• Receiver based
• Adaptive
• Compatible with existing transmitter
• DSP or analogue implementations