2015 06 23 super optical layer wdm nice 2015

© 2015 Xtera Communications, Inc. Proprietary & Confidential 1

Super Optical Layer Enabled by 16QAM and Raman Technologies

Bertrand Clesca – Head of Global Marketing – Xtera Communications23 June 2015

Next Generation Optical Networking 2015 (22-25 June 2015 – Nice, France)


Content:

• Why Long Spans Matter • Recent Technical Improvements

Enabling Longer Span (and Reach)• Example of Implementation• Raman Amplification, Key Enabler for 16QAM


Why Long Spans Matter


• Very meshy network with a lot of traffic locations

• Fibers owned, plenty of dark fibers available

Traditional Telecom Network


• Very sparse network with very few traffic locations long reach

• Fiber leased, but large pipes needed between few sites

• Technical/commercial benefits from site skipping long spans

Data Center Operator Network


• Technical + commercial innovations

• Instead of having back-to-back terminal equipment in red sites, long span capabilities enable to deploy optical line amplifiers in red sites or to skip some of these red sites.

Backhaul Networks for Subsea Cable Systems

London

Dublin


• Network made of leased fibers with few traffic locations

• Sparse population distribution and power availability issues long spans

Emerging Region Network


• Optical networks built over power grids

• By design, the fiber is routed to the foot of the transmission tower at very few locations long spans

OPGW Network


• Example in Papua New Guinea: Long spans imposed by the location of the liquid gas fields and plants

• Valid also for off-shore (and onshore in Middle East) oil rigs

Oil & Gas Industry’s Network

Hides GasConditioning

Plant

Kopi Scraper

266 km

Port Moresby

436 km

LNG plant


• New types of telecom networks with very few traffic locations– New players

– DC/PoP-to-DC/PoP network with subsea piece in the middle

• Deserts, mountains, rain forest or tundra are all examples of areas where intermediate amplifier sites can be prohibitively expensive to build, power, maintain and keep secure.

– Telecom networks in emerging countries with sparse populations distribution

and power availability issues

– Optical networks built over power grids

– Oil & gas industry

Why Long Spans Matter?


Recent Technical ImprovementsEnabling Longer Span (and Reach)


Optical Transmission Over Long SpanToo High Power: Nonlinear Limitation

Input eye diagram(NRZ signal)

Output eye diagram

Distance

Per

channel pow

er

pro

file

Nonlinear limitation

Amplifier power boost

Fiberattenuation

Pulsecompression(or distorsion)


Optical Transmission Over Long SpanToo Low Power: Noise Limitation

Opticalamplifier noise


Output eye diagram

Distance

Per

channel pow

er

pro

file


Fiberattenuation

Noise limitation


Optical Transmission Over Long SpanLimitations on Both Sides


Output eye diagram

Per

channel pow

er

pro

file

Nonlinear limitation


Noise limitation

Fiberattenuation

Pulsecompression(or distorsion)

Opticalamplifier noise

Distance


Optical Transmission Over Long SpanRaman Enabler: Line Fiber Becomes An Amplifier

Distance

Per

channel pow

er

pro

file

Fiberattenuation

Backward gain

Forward gain

BackwardRamanpumping

ForwardRaman

pumping

Adequate eye opening for proper signal detection


Output eye diagram


[Capacity – Reach] in Unrepeatered Links


Raman-Assisted TransmissionFor Multi-Span Transport

DistancePer

channel pow

er

pro

file

Lower limit: Optical noise accumulation

Upper limit: Nonlinear distortions

Highpeak-to-peakpowerexcursion

EDFA chain

A B C D E F

Powerboost

Fiberattenuation

Much lessbreathing

Higher noise performance

Raman chain

Lower non-linearity

A

Backward Raman pumping Forward Raman pumping

Fiber attenuation

Distributed Ramangain

B C D E F

Discreteamplifier


Raman-Assisted TransmissionFor Multi-Span Transport – All-Distributed Raman

DistancePer

channel pow

er

pro

file

Lower limit: Optical noise accumulation

Upper limit: Nonlinear distortions

Highpeak-to-peakpowerexcursion

EDFA chain

A B C D E F

Powerboost

Fiberattenuation

Further lessbreathing

Higher noise performance

All-distributed Raman chain

Lower non-linearity

A D

Backward Raman pumping Forward Raman pumping

Distributed Ramangain

Fiberattenuation

B C E F

Loss due to Raman amplifierinsertion loss


Example of Implementation


Power GridsInfrastructure Suitable for Optical Networks

• OPGW cable between transmission towers

• Not a telco network:– Long distances

between intermediate

ODF sites






ODF sites

– Telecom sites maybe

off the power grid






ODF sites

– Telecom sites maybe

off the power grid

Very long spans


TIM BrasilLong Links with Ultra-Long Spans on OPGW Cables

1,161 kmlink

Amazonas Project: 2,266 km network(1,835 km OPGW cable

infrastructure)

ManausGopa

Macapá

Belem

JurupariFortaleza

Salvador

Tucuruí

Puerto Velho

Cuiabá

1,010 kmlink

1,645 kmlink

TIM BrasilLong Links with Ultra-Long Spans on OPGW Cables


Ultra-Long Spans in 2,266 km Amazon Network(Highest Span Loss: 63 dB)

ROADM

43 km13.9 dB

237 km53.8 dB

278 km63.1 dB

ILAILA ROADM

142 km34.6 dB

ILA

138 km33.1 dB

235 km53.5 dB

ILAVilla

Camburão

ROADM

183 km46.1 dB

141 km33.9 dB

157 km37.2 dB

ILAILA ILA

91 km23.8 dB

ILA

229 km52.8 dB

ROADM

239 km54.2 dB

110 km27.2 dB

ROADM

ILA ILA

43 km13.9 dB

ManausTIM

Terra SantaManausRod Lexuga

Silves Oriximiná

MacapáTIM

Jurupari

Macapá Sub Laranjal do Jari

Gopa XinguTucuruí Pacaja Vitória do Xingu

Coreamplifier

Backward spanextension module

Forward spanextension module

G.652fiber span


• Wise RamanTM solution backed by:– An unrivalled 17 years of tremendous and unique R&D experience

– An unparalleled 11 years of commercial deployments worldwide

• Wise RamanTM solution covers all the aspects of optical networks relying on Raman amplification:

– Modeling

– Photonics

– Link engineering

– Network design

– Hardware

– Firmware

– Software

– Network management

Not simply the addition of third-partyRaman pump modules to EDFA amplifiers that were designed for stand-alone usage!

Wise RamanTM By Xtera

Raman amplifier controller is key, and quite different from EDFA controller.


Raman Amplification,Key Enabler for 16QAM


100/200/400G Implementations

Polarization Multiplexing(PM)

Multi-level modulationformat

25 Gbaud opto-electronics

Dual-carrierimplementation

N-level modulation format + Coherent detection + Digital signal processing

25 Gbaud 200 Gbit/s100 Gbit/s

16QAM200GPM-16QAM

I

Q

1011

1010

1101

1111

1001

1000

1100

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0010

0000

0100

0101

0011

0001

0110

0111


QPSK100GPM-QPSK

00

I

Q

10

1101

l

400 Gbit/s


16QAM400GDC-PM-16QAM

I

Q

1011

1010

1101

1111

1001

1000

1100

1110

0010

0000

0100

0101

0011

0001

0110

0111

≈ 50 GHz

(or narrower)


• Higher OSNR requirement

• Higher sensitivity on fiber nonlinearities

Practical reach in real network environment with EDFA-based equipment: 600 km.

• 400G or 1T channels are made, today, on the combination of2 or 5 x 200G PM-16QAM carriers.

• Higher-end line equipment is required to extend the optical reachof PM-16QAM carriers.

16QAM Challenges


16QAM200GPM-16QAM

I

Q

1011

1010

1101

1111

1001

1000

1100

1110

0010

0000

0100

0101

0011

0001

0110

0111


[Capacity – Reach] Metric Enabled byXtera’s Wise RamanTM in Terrestrial Networks

240 x 100G• 100 nm spectrum• PM-QPSK 100G carriers with

50 GHz channel spacing• 2 bit/s/Hz spectral efficiency

120 x 400G• 100 nm spectrum• PM-16QAM 200G carriers

spaced 50 GHz apart• 4 bit/s/Hz spectral efficiency

160 x 400G• 100 nm spectrum• PM-16QAM 200G carriers

spaced 37.5 GHz apart• 5.3 bit/s/Hz spectral efficiency

16QAM on more than 2,000 km of aged terrestrial fiber (0.28 dB/km)


[Capacity – Reach] Metric Enabled byXtera’s Wise RamanTM in Terrestrial Networks


Innovative Supplier Of Long-Haul Optical

Transmission Infrastructure

Aerial

Terrestrial

Submarine

2015 06 23 super optical layer wdm nice 2015

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