1. Josep Prat Universitat Politècnica de Catalunya (UPC) Barcelona
EU-Japan Workshop, Brussels 18-April Research on Next Generation Optical Access Networks
Josep Prat
Universitat Politècnica de Catalunya (UPC) Barcelona

2. Optical access evolution
WDM -
PON
xWDM
CAPACITY, cost (per user)
ngPON 1
ngPON 2, 3 ..
FTTH
WDM-PON
ultra-dense WDM-PON E (OFDM) / Coh 1G
100M
FTTH-PtP
WDM&TDM-PON
HFC
FTTH
XG/G/E-PON
xDSL
10M
ADSL
TIME
POTs
2008
2013
ACCORDANCE
SARDANA
COCONUT
EU projects:
EUROFOS NoE
MUSE IP
ALPHA IP
OASE IP
DISCUS IP

3. PON Optical spectrum possible bands for ngPON3 (with compatibility) :
FSAN-ITU Estandards: ?
1260
1270
1280
1290
1300
1310
1320
1330
1340
1350
1360
G-PON
upstream
XG-PON
1480
1490
1500
1510
1520
1530
1540
1550
1560
1570
1580
1590
1600
1610
G-PON
downstream XG
Video
NG2 10 10
possible bands for ngPON3
(with compatibility) :
40 nm
Video: IP
EDFA
Low loss fiber
High availability of comp.
40 nm / 6.25 G = 800 channels !!
CAPACITY x 100 !!

4. E/O BW & power Efficiency
Statistical WDM multiplexing
Time-switched phase diversity&modulation
1000%
EF = Rb / BWD
RoF
OFDM
Electrical Spectrum Efficiency
ud-WDM
100%
10%
WDM/TDM
GPON 1%
XG-PON
0.1%
PowerComsp.:
= a C Vd2 fr + Io 10Vt/S Vd
x Activity %
0.01%
0.1% 1%
10%
100%
Optical Spectrum Efficiency

5. PON alternatives GPON XGPON TWDM-PON cUDWDM-PON WDM-PON SCM/OFDM-PON
Aggregate BW
2.5/1.25
10G/2.5
40G/10G
>40G
Depends on type
Good if combined with WDM
Granularity
(min BW/user)
1 AWG port assigned
N subcarriers
1G-10G Good if +TDM
Complexity, cost
Tunable TRX ONUs
Up-stream or tunable laser
Upstream, PAPR, optical amplif. or coherent
Coherent RX, random/tunable lasers ?
Energy efficiency
BWuser / G
BWuser / G
If ONU only handles assign. subc.
User rate = line rate
Optical spectrum efficiency
Good if combined with WDM or coherent
Power budget
best
Incremental scalability (n.,BW)
Limited by device, AWG, or RBS
Compatibility
AWG
Sensitivity issue
Wireless
Splitter if coherent det.

6. SARDANA project
Scalable Advanced Ring-based passive Dense Access Network Architecture”
Activity: ICT Network of the Future Grant agreement n.: (SARDANA) STREP: , 2.6 MEuro
Participant name
Short name
Country 1
Universitat Politecnica de Catalunya
UPC
Spain 2
France Telecom / Orange FT
France 3
Tellabs
TELLABS
Finland 4
Intracom S.A. Telecom Solutions
IntraCOM
Greece 5
Instituto de Telecomumicações IT
Portugal 6
High Institute of Communication and Information Technology
ISCOM
Italy 7
Research and Education Laboratory in Information Tech.
AIT 6

7. SARDANA architecture def.
Resilient trunk
Fully passive
Hybrid:
WDM Metro ring
TDM Access trees
Cascadable remote nodes
New adoption of remotely-pumped amplification
Colourless ONU
RSOA
Tunable laser
10G-2.5G (1G-100Mb /user)
100 Km
1000 users
Multi-operator
Based on xGPON, but transparent.
IP trafic
SARDANA PON

8. SARDANA inter-operability & multi-operability

9. 3 testbed demonstrations
Stakeholder demo in Espoo (Finland) in October 2010 (integration and tests)
Field trial in Lannion (France), in January over the metropolitan 12x 18 Km ring cable
Public demo at the Exhibit of FTTH Council Europe 2011, in Milan in February 2011.

10. ACCORDANCE STREP project
A Converged Copper-Optical-RaDio OFDMA-based Access Network with High Capacity and FlExibility
Objectives
Consortium
Definition of a novel Access Network architecture achieving convergence among heterogeneous technologies (optical, wireless, copper).
Propose low-cost, low-complexity concepts to achieve ultra high data rates in the access network (up to 100Gbps aggregate and more than 10Gbps in each segment).
Introduction of flexible bandwidth allocation concepts using dynamic FDM and OFDM sub-carrier assignment.
Provision of smooth migration from and coexistence with legacy access solutions.
Demonstration of the ACCORDANCE concepts using experimental test beds.

11. OFDM-PON (ACCORDANCE STREP project)
Envisioned Converged Network Architecture
Integrated
DEMO

12. Indicative experimental results by ACCORDANCE partners:
OFDM-PON system
OLT
ONU
Indicative experimental results by ACCORDANCE partners:
R. Schmogrow et al., “101.5 Gbit/s Real-Time OFDM Transmitter with 16QAM Modulated Subcarriers” , OFC’11
OFC’13: P. Schindler et al. OW1A.5

13. Flexible BW Allocation to deal with:
the Power difference between (ONU1-ONU2)
for proper detection at BER=10-3, leaving ONU1 with B(Q)PSK modulation 50 40 30 20 10
ONU2 BW occupation [%] 50 40 30 20 10
ONU2 BW occupation [%] f e d c b a
(the mod. Index is kept, hence for lower amount of subcarriers, the ratio between levels increases allowing to have higher SNR → relaxing the receiver sensitivity) a b c d e f
The high BW granularity allows OFDMA to deal with differential link loss among users.

14. Example of ACCORDANCE MAC Scheduling
Various options possible:
Multiple subcarriers per ONU (hybrid OFDMA/TDMA)
Multiple ONUs per subcarrier (TDMA)
PHY/MAC Cross-layer optimization
Use of Adaptive Subcarrier Modulation (ASM)
Use a different m-QAM for each ONU based on transmission performance
MAC takes into account different bitrates for a subcarrier each time, depending on the allocation
Lower delay for same traffic, i.e. capacity is effectively increased

15. COCONUT project: Coherent UD-WDM
Can we improve the spectral efficiency in both optical&electrical domains?
and the BW?
and optical fine granularity ?
and the Power budget?
Proposal: Coherent UD-WDM with random-wavelength DFB lasers

16. COCONUT
COst-effective COhereNt Ultra-dense-WDM-PON for lambda-To-the-user access
STREP , ICT Objectives 1.1 a) b)
1st-Nov + 36 months
Coordinator:
SSupSA (Ernesto Ciaramella)
Vice-coordinator: UPC (Josep Prat)
GOAL: efficient lTTH
1G-to-the-Home + 10G-to-the-Antenna
By: ultra-dense WDM-PON, by:
Statistical WDM multiplexing
Simplified coherent transmission
10th Concertation Meeting, October 2012

17. What Ligh Source at Home for WDM ?
Requirements:
All the same : colourless (wavelength agnostic)
for feasible provisioning and high volumes fabrication
Broadband: > 1GBit/s
Possible solutions:
Tuneable laser : still expensive and non-repetible
Reflective SOA, wavelength remodulation: limited perform.
Random-wavelength laser !?
Statistical multiplexing
CO adapts to ONU
Benefit of chaos ..!

18. Wavelength contention statistics
Grid= 6.25GHz
Total BW = 30nm
Uniform laser statistical distribution
Max. N. users = 600
Thermal 2nm (DFB)
(Results 1000 times aver.)
With thermal tuning
Without thermal tuning
~ 1 ONU in 512 to replace
Spectral efficiency:
Periodical allocation: 16 %
Statistical allocation: 14%

19. NGPON2/3 arch. features comparison
XG-PON
TWDM
WDM/TDM-PON
OFDM-PON **
UD-WDM
Aggregate BW
10 GBit/s
40 GBit/s
320 GBit/s
GBit/s x8
512 GBit/s
User data*
MBit/s
MBit/s
50M-1G Bit/s
100 MBit/s
1 GBit/s
Bit rate
GBit/s
ONU Elec. BW
kHz - 10GHz
kHz - 10GHz
Fi – Fi+50MHz
MHz - 1 GHz
Elec.Spectrum Eff.(up)
0.5% 1%
0.5% - 10%
< 200%***
< 200%
Number of users 32
128
512
Wavelength Channels
1-2
4-8
1-8
Wavelength Spacing -
100 GHz
GHz
>50 GHz
GHz
Optical Spectrum Eff. (up)
10%
20-40%
1% - 20% %
Passive distance reach
20 km
20 Km
60 km
100 km
COST (per user, 1G, relative) 1 2
3 – 0.8
26 - 1
10 – 0.8
ENERGY C. (per user, relative)
2 – 0.8
10 – 0.7
Added features
compatibility
protection, metro-access converg.
wired&wireless convergence, SC-DBA
user independency
splitter
Issues
Tunable ONU
Colourless ONU, Optical remote pump power
Up-stream OBI, PAPR, Sensitiv.
Wavel.tuning,
polarization
(typical-mean values) * Symmetrical PON; ** 16QAM; *** Only odd carriers used.

20. Possible colaboration research topics
Definition of requirements, test of solutions and standardization steps towards NGPON3, implementing the concept of lambda-to-the-home lTTH
from 100 Mb  to 10 Gb to each home or antenna site
Development of low cost phase-modulated lasers for elastic coherent udWDM-PON.
Global Convergence of udWDM wired access, wireless and metro networks, in physical, MAC and control plane layers
current collaboration between NEC and Accordance/AIT
All optical processing with OCDMA multiplexing, transmission and GMPLS routing
topic in joint research by NICT, RomaTre, Aveiro Univ.
Extension of the concepts and techniques to smaller ranges:
CORE -> ACCESS -> LOCAL WIRED AND WIRELESS

21. THANKS! Acknowledgements:
European 7th Framework Programme project SARDANA (
European 7th Framework Programme project ACCORDANCE (
European 7th Framework Programme Network of Excellence EUROFOS (
European 7th Framework Programme project COCONUT (