MultiWavelength Optical Networks

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Multi-WavelengthOptical Networks
Eric T. Hennessey
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Introduction

• Nortel Networks
• Why Optical Networks?
• Principles of Operation
• Dense Wavelength Division Multiplexing
• Complications
• Mid-Span Access Equipment
• My Role

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Definitions

• DWDM
• Dense Wavelength Division Multiplexing
• Many signals on one fibre
• 20,643,840 telephone conversations!
• OADM
• Optical Add/Drop Multiplexer
• Signal routing at the optical level

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Optical Links

• From network node to network node
• One signal 10 Gigabits per second

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DWDM Illustrated
Optical Nodes
Data Sites
Optical Coupler
Optical Amplifier
129,024 telephones
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Electromagnetic Spectrum

• Visible Blue Band
  Red Band
• 400-700 nm 1527-1543 nm 1547-1561 nm

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Signal Quality

• Optical Signal to Noise Ratio
• Optical Spectrum Analyzer

Optical Signal
Noise Floor
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Optical Spectrum Analyzer
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Complications

• Optical Fibre Power Loss!
• absorption in fibre material
• Amplifiers Noise!
• natural decay of erbium ions

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Signal Degradation Illustrated
Optical Signal
First Noise Floor
Noise Floor
Optical Amplifier
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OADM Sites
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OADM Illustrated
Optical Fiber
1557.36nm
1555.75nm
OADM Sites
1535.04nm
1533.47nm
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OADM Illustrated
Optical Fiber
1557.36nm
1555.75nm
OADM Sites
1535.04nm
1533.47nm
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OADM Illustrated
Optical Fiber
1557.36nm
1555.75nm
OADM Sites
1535.04nm
1533.47nm
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OADM Illustrated
Optical Fiber
1557.36nm
1555.75nm
OADM Sites
1535.04nm
1533.47nm
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OADM Illustrated
Optical Fiber
1557.36nm
1555.75nm
OADM Sites
1535.04nm
1533.47nm
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OADM Illustrated
Optical Fiber
1557.36nm
1555.75nm
OADM Sites
1535.04nm
1533.47nm
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My Role

• Construct 32 Wavelength Networks
• Signal Quality Observations
• Different Equipment
• Different Configurations
• Systems Resource

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Conclusion

• The Purpose
• The Function
• Dense Wavelength Division Multiplexing
• Mid-Span Access
• Issues
• The Task