Presentation of the test results of 40/100Gb transponders over 4000 Km Submarine Cable.

1. 125-Gb/s CP-QPSK Field Trial over 4108 km of
Installed Submarine Cable
Vladimir Veljanovski1, Vincent Sleiffer2, Dirk van den Borne1, Joe Capasso3,
Hayri Kuluslu3, Jose Seixas3, Volker Schramm3, Alexander Tschersich1,
Rogerio Nogueira4, Natasa Pavlovic4, Kristofer Ivarson3, Stefan Spaelter1,
Huug de Waardt2
1: Nokia Siemens Network GmbH & Co. KG, Munich, Germany (vladimir.veljanovski@nsn.com).
2: COBRA institute, Eindhoven University of Technology, Eindhoven, The Netherlands.
3: Nokia Siemens Networks US LLC., Iselin, NJ, USA.
4: Nokia Siemens Networks Portugal SA., Lisbon, Portugal.
1 © Nokia Siemens Networks Dirk van den Borne / 16-12-2010

2. Motivation
A decade ago, many 10G optimized submarine networks have been deployed to
fuel the traffic growth of the emerging Internet.
Transponder technology has progressed immensely over the last 10 years,
cumulating in 40G /100G polarization-multiplexed BPSK/QPSK solutions.
This opens up the possibility of extending the life time of deployed submarine
cables through an increase of the design capacity by a factor of 4x / 10x, delaying
the B$ investment in new cable deployments.
The goal of this field trial is to demonstrate the feasibility of a capacity
upgrade to 100G line rates over ultra long-haul deployed submarine cable.
2 © Nokia Siemens Networks Dirk van den Borne / 16-12-2010

3. Submarine Cable
Submarine network deployed in 2001
Cable segment: Boca Raton, USA –
San Juan, Puerto Rico.
Distance: 2054 km (uni-directional)
or 4108 km (bi-directional).
Spans: 36 spans with a typical span
length of 57 km.
Dispersion map: Hybrid map with a
combination of NZDSF with D = -2ps/nm/km
and NDSF with D = 20ps/nm/km, the zero
dispersion wavelength of the segment is at
1550 nm.
3 © Nokia Siemens Networks Dirk van den Borne / 16-12-2010

4. Terminal equipment setup
Segment H
Loading channels
40G CP-QPSK channels have a 1.5 dB
lower channel power compared to the
100G CP-QPSK channel under test.
Transmitter-side optical spectrum
4 © Nokia Siemens Networks Dirk van den Borne / 16-12-2010

5. 40G CP-QPSK over 4108 km
Transmission performance of 40G CP-QPSK transponders over the 4108-km
long submarine link.
Significant impact of inter-channel nonlinear impairments.
Worse performance in the middle of the transmission band. Measured Q-margin is approx.
1.8 dBQ for the center channel, >2 dBQ for the other channels under test.
13 13
12 12
11 11
10 10
Q [dB]
Q [dB]
9 9
~1.8dB
8 8
FEC threshold FEC threshold
7 Single Ch. 7 192.55 THz
100 GHz WDM 193.15 THz
6 50 GHz WDM 6 194.25 THz
5 5
-12 -10 -8 -6 -4 -2 0 -12 -10 -8 -6 -4 -2
Channel input power [dBm] Channel input power [dBm]
5 © Nokia Siemens Networks Dirk van den Borne / 16-12-2010

6. 100G CP-QPSK over 2054 km
Measured Q-factor as a function of the input power per channel and optical
pre-compensation at 193.15 THz (middle of the band).
Small impact of inter-channel nonlinearities, and both single channel and WDM
configurations show close to the same performance.
Approximately 3 dBQ margin for all configurations.
11 11
Single channel 100GHz WDM
100GHz WDM
10 50GHz WDM 10
9 9
Q [dB]
Q [dB]
~3dB
8 8
7 7
FEC threshold FEC threshold
6 6
-12 -10 -8 -6 -4 -2 0 -3000 -2000 -1000 0 1000 2000
Channel input power [dBm] Pre-compensation [ps/nm]
6 © Nokia Siemens Networks Dirk van den Borne / 16-12-2010

7. 100G CP-QPSK over 4108 km
Measured Q-factor as a function of the input power per channel and optical
pre-compensation at 193.15 THz (middle of the band).
More pronounced performance difference between single channel and 50GHz channel
spacing.
Measured Q-margin is 0.9 dB for 100 GHz spacing, and 0.6 dB for 50GHz channel spacing.
9 9
8 8
FEC threshold
7 FEC threshold 7
Q [dB]
Q [dB]
0.6dB
6 6
5 Single channel 5
100GHz WDM Single channel
50GHz WDM 100GHz WDM
4 4
-12 -10 -8 -6 -4 -2 0 -3.000 -2.000 -1.000 0 1.000 2.000
Channel input power [dBm] Pre-compensation [ps/nm]
7 © Nokia Siemens Networks Dirk van den Borne / 16-12-2010

8. Submarine Cable
Cable segment: San Juan, Puerto Rico
to Fortaleza, Brazil. Puerto Rico
Distance: 9392 km (bi-directional).
Brazil
Segment G
Segment H
Rx spectra after 9392 km San Juan
8 © Nokia Siemens Networks Dirk van den Borne / 16-12-2010

9. 40G CP-BPSK over 9392 km
Measured Q-factor as a function of the input power per channel and optical
pre-compensation at 193.15 THz (middle of the band).
Measured margin of 3.6 dB for single-channel transmission, and 2.2 dB for 50GHz
channel spacing.
11 11
Single Channel Single Channel
10 50GHz WDM 10 50GHz WDM
9 9
Q [dB]
Q [dB]
8 8
7 7
2.2dB FEC threshold
6 6
FEC threshold
5 5
4 4
-12 -10 -8 -6 -4 -2 0 -3000 -2000 -1000 0 1000 2000
Channel input power [dBm] Pre-compensation [ps/nm]
9 © Nokia Siemens Networks Dirk van den Borne / 16-12-2010

10. Summary & Conclusions
This field trail demonstrates the feasibility of upgrading existing submarine
cables with state-of-the-art 40G/100G coherent transponder technology.
Successful demonstration of 100G CP-QPSK transmission over 4108 km of
legacy submarine cable.
Ultra long-haul transmission of 40G CP-BSK over 9392 km of legacy
submarine cable.
Demonstrate compatibility of co-propagating 100G and 40G CP-QPSK
channels over same fiber.
Existing submarine links can be upgraded to 100G line rates, thereby
significantly extending their design capacity and delaying the need for
new cable deployments!
10 © Nokia Siemens Networks Dirk van den Borne / 16-12-2010

11. THANK YOU!
11 © Nokia Siemens Networks Dirk van den Borne / 16-12-2010