Towards Terabit Optical Networks
Júlio César R.F. de Oliveira, Ph.D
Optical Systems Manager, CPqD
Summary
Optical Transmission – 100G, 400G, ..... , NxTb/s
Optical Networking – Amps., ROADMs, Controlability
Microelectronics for Coherent Transmission (ASIC DSP/OTN)
Integrated Photonics (Modulators, Receivers, Monitors,...)
Conclusions
28-Gbaud
QPSK
Modulation
Format
Number
Subcarriers
Baud Rate
(Gbaud)
2 4 16
14
28
32
1
2
8
10
28-Gbaud
16QAM
100G
28-Gbaud
16QAM
200G 400G
28-Gbaud
16QAM 28-Gbaud
QPSK
1T
112 Gb/s
QP
SK
16
QA
M
448 Gb/s
16
QA
M
224 Gb/s
16
QA
M
1.12 Tb/s
Toward Terabit Systems
QP
SK
QP
SK
1.12 Tb/s
448-Gb/s dual-carrier PDM-16QAM
25GHz
56GHz
112GHz
56GHz
35GHz
25GHz Pre-filtering
35GHz spacing
between the two
carriers
75GHz
Two 50% RZ carriers
Occuping a
112 GHz grid
Two 50% RZ carriers
occuping a 75GHz grid
112GHz
Higher performance, spectral efficiency
and filtering robustness
448-Gb/s dual-carrier PDM-16QAM
Higher performance, spectral efficiency
and filtering robustness
Mux
PRBS
PDM-QPSK Modulator
EDFA 3 dB PBC
PDM Emulator
Pulse
Carver
5x1
Odd
50
km
50
km
50
km
50
km
EDFA EDFA EDFA EDFA
EDFAEDFA
26
km
SW 13 dB
SW 2
Pol.
Div.
Hyb.
90°
Ort
ho
no
rma
liza
tio
n
De
ske
w
Po
lariza
tio
n D
em
ux
Ca
rrie
r R
eco
ve
ry
De
mo
du
latio
n
Offline DSP
WSS
(e)
LO
Clo
ck R
eco
ve
ry
SC
OP
E (
40
-GS
/s)
3 dB
Mux
PRBS
PDM-QPSK Modulator
EDFA 3 dB PBC
PDM Emulator
Pulse
Carver
5x1
Even
Wa
ve
Sh
ap
er
CD
Co
mp
en
sa
tio
n
RZ-PDM-16QAM Eye
RZ-16QAM Eye
(b)
Pol. Incidence
angle of 26.5°
(a)
(c) (d)Modulation Format DP-16QAM
Carriers 2
Baud rate 28 G
SE 5.6 b/s/Hz
Grid 75 GHz
Reach 678 km
Optical Superchannel: 1.12-Tb/s
1000 km of
optical fiber!
Features
Baud rate 28 Gb/s
Modulation RZ-PDM-16QAM
Total bit rate 1 Tb/s
Bit rate per carrier 224 Gb/s
Carrier spacing 35 GHz
Spectral Efficiency
6 b/s/Hz
Spectral Occupancy 175 GHz
Reach 1000 km
Feasible application Metropolitan Networks
Modulation
Format
Number
Subcarriers
Baud Rate
(Gbaud)
2 4 16
14
28
32
1
2
8
10
100G
28-Gbaud
16QAM
200G 400G
28-Gbaud
16QAM
1T
OFDM has been also investigated…
12.5-Gbaud
QPSK
12.5-Gbaud
16QAM
Tx
Rx
Comb
Gen.
Key-module: Comb Generator
Stable
Equilized-Power
Broadband
450 Gb/s CO-OFDM DP-QPSK (9 carriers)
Comb-generator
After 226km After 2260km After 3840 km
Modulation Format DP-QPSK
Carriers 9
Baud rate 12.5 G
SE ~4 b/s/Hz
Grid 112.5 GHz
Reach 3840 km
400-Gb/s CO-OFDM DP-16QAM (4 carriers)
Feedback – comb generator
Features
Baud rate 12.5 GBd
Modulation PDM-16QAM
Total bit rate 400-Gb/s
Bit rate per carrier 100-Gb/s
Carrier spacing 12.5-GHz
Spectral Efficiency
6.4 b/s/Hz
Spectral Occupancy 62.5-GHz
Reach 450 km
Feasible application Metropolitan Networks
Flexible-Transmitter for Terabit applications
3 Carriers Test Features
Feasible
application
Metropolitan
Networks
Long-Haul
Networks
Modulation RZ-PDM-16QAM RZ-PDM-QPSK
Baud rate 28 Gb/s 28 Gb/s
Bit rate per
carrier 224 Gb/s 112 Gb/s
Total bit rate 672 Gb/s 336 Gb/s
Carrier spacing 33.6 GHz 30.8 GHz
Spectral
Efficiency 6.25 b/s/Hz 3.41
Spectral
Occupancy 100.8 GHz 92.4 GHz
Reach 900 km 4900 km
3 Carriers
Transmission
Evaluation
-Quasi-Nyquist spacing
- Upgradable transmitter;
- DSP-Tx free;
- Reach adaptable
Field Trials: Terabit systems
Giga Network Setup
Terabits CO-OFDM DP-QPSK 12.5 GBaud RF
Sinusoidal
33 dBm
AM PM PM
Phase
shiftPhase
shift
Phase
shift
17 dBm
Pol.
rotator
12 dBm
27 dBm 27 dBm
15 dBm 2 dBm
Flexigrid WSS
12.5 GHz
AM: Amplitude Modulator
PM: Phase Modulator
23 CO-OFDM
Carriers
1551 nm
PM EDFA
23 dBm18 dBm
Pol.
rotator
CW
Laser
RF
Sinusoidal
33 dBm
AM PM PM
Phase
shiftPhase
shift
Phase
shift
17 dBm
Pol.
rotato
r
12 dBm
27 dBm 27 dBm
15 dBm
12.5 GHz
AM: Amplitude Modulator
PM: Phase Modulator
1551 nm
PM EDFA
23 dBm18 dBm
CW
LaserPol.
rotator
3 dB3 dB
Flexigrid WSS
Flexigrid WSS
Pol.
rotatorPol.
rotator
Modulation Format DP-QPSK
Subcarriers 23
Baud rate 12.5 G
SE 3.5 b/s/Hz
Grid 300 GHz
Reach 4520 km
Modulation Format DP-QPSK
Subcarriers 45
Baud rate 12.5 G
SE 3.65 b/s/Hz
Bandwidth 575 GHz
Reach 338 km (GIGA)
High Speed DAC 34GS/s High Speed DAC 65GS/s
Digital (Pre)Filtering
34GS/s DAC (N-QAM) - 2012
16-QAM
256-QAM 64-QAM
QPSK
65GS/s DAC (N-QAM) - 2013
QPSK 16QAM 32QAM 64QAM
65GS/s Nyquist Filtering Results (Preliminar)
CPqD Coherent Transmission Evolution
100 Gb/s 200 Gb/s 400 Gb/s 1 Tb/s ... 2 Tb/s
Transmission Results summary (CPqD)
Bit rate [Gb/s] Modulation Carriers Baud rate [GBd] SE [b/s/Hz] Reach [km] Capacity [Tb/s]
112 PDM-QPSK 1 28 2.1 3200 Long-H
224 PDM-16QAM 1 28 4.2 680 Metro/Long-H
400 PDM-16QAM 4 12.5 6.4 450 Metro/Long-H
448 PDM-16QAM 2 28 5.6 680 Metro/Long-H
450 PDM-QPSK 9 12.5 3.36 3840 Long-H
1120 PDM-16QAM 5 28 6 1000 Long-H
1120 PDM-QPSK 10 28 3.41 450 Metro/Long-H
1150 PDM-QPSK 23 12.5 3.5 4520 Long-H
2250 PDM-QPSK 45 12.5 3.65 338 (GIGA) Metro/Long-H
100G Coherent Optical Module
Network Monitoring
Cognitive
Management and Control
Central
Office
Understanding the network
Adding intelligence to the network
...
HNLF EDFA/Raman AMP
Raman Pump
GMPLS Control Plane
- Network Registration -Topolgy Discovery - Route wavelength Assingment (RWA);
Tx/Rx
Degree 1
Degree 2
Degree 3 Degree n
RO
AD
M
Tx/Rx
RO
AD
M
Read Monitoring
Cognitive/Smart Processing
Self-Configurable/
Cognitive
WDM Network
Network actuation
TDCM TPMD
- Network Monitoring (OLMP): - Input/Output Power - Channel Power - OSNR - BER (Pre and Post FEC) - Chromatic Dispersion - PMD
Authonomic Networks
Optical Networking Testbed (Logical Layer)
TODAY
• SDN + GMPLS optical network concept
• Network monitor/process/control algorithms
to enable smart optical network;
• Adaptive and cognitive EDFA;
• Network Discovery and Abstraction;
Further Works
• Adaptive and Cognitive ROADMs
• Optical Network Auto- Alignment
• UNI-C and UNI-N
• Automatic Fault Restoration
• Fault Prediction
• Spectrum defragmentation
• Hitless networks
• Integration with OTN-S
Optical Networking Testbed (Physical Layer)
Laboratorial Testbed
Testbed Topology
Developed Line Cards
(HW/FW)
In-Band OSNR Monitor (Pol. Diversity & Interferometric)
Filter
50GHz
PBS DSP
Driver
Tx
EDFA
SMF
TAP Rx
SMF
EDFA
τ
OSNR Monitor
CD = 0 ps/nm & DGD = 0 ps CD = 750 ps/nm & DGD = 45 ps ECOC2013 Submitted
Adaptive and Cognitive Optical Network Algorithms
Adaptive EDFA (PTL in submission)
• EDFA Noise Figure and Flatness
operation point optimization on-line
Cognitive EDFA without
launch power (LP)
BER ok ?
Cognitive EDFA with
launch power (LP) 1
All BER
ok ? LP2 = LP1++
END
END
-2 dBm (16-QAM)
0 dBm (CO-OFDM)
2 dBm (16-QAM)
4 dBm (CO-OFDM)
Cognitive EDFA (OFC2013)
• Adaptive EDFA + Channels BER history to
adjust best launch power (error free for att. 6 dB)
Fail
OK
Fail
OK
Fail
OK
Fail
OK OK
OK
OK OK
BER
reduction
¹Cog. action transient time
² Attenuation event Occur
With cog.
(new Gains)
Without
cognition
(same gain) ¹
²
Line card development
Optical Amplifiers
(Optimized)
• EDFA
• Raman Amp.
• Hybrid Amp.
C/L Band
Routing and Monitoring
• PLC and WSS ROADMs;
• Optical Channel Monitoring ;
• CDC Multi-Cast-Switch;
Tech.
Transfer
2013 - ASIC DSP
ASIC DSP - (BPSK/QPSK/16-QAM)
ASICs DSP – Microelectronic Flow
Logic Synthesis (Test case 1)
Physical Synthesis results Test case 1 (auto FP&R)
ASIC OTN 100G
Framer / Deframer
OTU-4
Map
per
s/ D
emap
ers
(SD
H /
FC
/ G
bE
/ OT
N)
Inte
rfac
e 1
Inte
rfac
e 2
Mux / Demux
FEC
EFEC
OTN Processor
ASIC OTN
OTN – GbE – SDH – FC
OTN
100 Gbit/s
ASIC OTN
Integrated Photonics
- Chip in fabrication (MPW Si run)
- Components and Devices
- Coherent DP-QPSK Modulators
- Coherent Receivers
- OSNR in-band monitor
- PSGC (Pol. Splitter)
- Grating, resistors, PDs, ...
Integrated Photonics (PSGC – CPqD Design)
Electric Field Amplitude Distribution
60 mm
33 mm
Integrated Photonics (Packaging)
CPqD Strategy – Towards Terabit Optical Netwoks
Design and packaging
coherent linecard critical
components
Cognitive Optical Networks
(GMPLS/SDN, Amps,
ROADMs, Monitoring)
100 Gb/s 200 Gb/s
400 Gb/s 1 Tb/s
Coherent transmission
evolution towards NxTb/s
Focus on
INDUSTRY
(Products)
Conclusions
- Fast evolution on optical transmission due to coherent, 100G is a reality, 400G will be the
next step and 1T technologies are feasible in lab. right now
- Coherent evolution demands new technological domain (DSP, microelectronics, integrated
photonics) and generates high dependence in transmitters critical components (ASICs,
Mod./Rx), that require massive investments, CPqD with governamental and industry support
are developing this systems and components to enable the growth of national WDM systems
-Optical networks evolution trough Hybrid Amplifiers, ROADMs, Control Plane and
Monitoring are under fast development
- The evolution of optical communications are critical to world wide interconnect and plays a
key social role in any country in the world, this field are under continuous evolution with a
fast established cycle between R&D and market, enabling the broadband evolvution in a
sustainable way!!!!!!
Acknowledgements
Thank You!
www.cpqd.com.br