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Page 2Copyright © Infineon Technologies 2008. All rights reserved. 2009/09/29
Infineon Wireline Communication
! ADSL/VDSL! Network
Processor! VoIP! Ethernet! WLAN! DECT modems
Carrier Access(CA)
Voice Infrastructure
(VI)Customer Premises
Equipment(CPE)
! ADSL/SHDSL/VDSL! Access Network Processors! Voice/VoIP
! T/E Carrier! HDLC! ATM/IP! ISDN! DECT
DSL CPEHome Network
IP-DSLAM/ MSAN
Cellular Backhaul
Page 32009/09/29 Copyright © Infineon Technologies 2008. All rights reserved.
Broadband Infrastructure Drivers for 2009/10
IPTV/Video enters growth stage1
NGN deployments starting2
3 Mobile broadband drives investment in backhaul network
Broadband white spots drive investment for rural areas
4
Page 4Copyright © Infineon Technologies 2008. All rights reserved. 2009/09/29
Next Generation Network (NGN)
DSLAM
INTERNET
Customer Premises
Splitter
CPE
Copper Line
VOICE
TV
Next Generation Network (NGN)
All-IP
" Drivers for Telecom Operators:
# Reduction of network elements
# Real estate and OPEX
# Flexible service bundling
" Deployment Concepts:
# All-Digital DSL + multiservice CPE
# FTTx + multiservice MDU/ONT
" Operator Requirements:
# Maintain Quality-of-Service level
# Reuse of network test and customer support infrastructure
" Technology Requirements:
# Transition to VDSL2 / GPON
# Integrated MELT + DSL
# Decentralized Voice aggregation
Key Elements of NGN
DSLAM
INTERNET
Customer Premises
Splitter
CPE
Copper Line
Splitter
VOICE
TVCable/Satellite/DVB-T
POTS
Traditional Network Architecture
ATM
Page 5Copyright © Infineon Technologies 2008. All rights reserved. 2009/09/29
Future Challenges for DSL Systems …
Line Management /
Testing
reduced
Power Consumption
increased
Stability
increased
Datarate
Page 6Copyright © Infineon Technologies 2008. All rights reserved. 2009/09/29
Agenda
" Introduction xDSL
" Datarate Increase – Vectoring
" Stability Improvement – Retransmission / Virtual Noise
" Line Testing – Metallic Access Line Testing (MELT)
" Power Consumption
Page 8Copyright © Infineon Technologies 2008. All rights reserved. 2009/09/29
xDSL Technology Overview
" DS data rate
" US data rate
" Typ. loop length
" Layer 2 Transp.
" Typ. Deployment
" Max. Signal BW
" Modulation DS
" Modulation US
" Transmit Power
" Coding
" POTS / ISDN
ADSL /ADSL2
16 Mbps
1~3 Mbps
12…20 kFt
ATM(Eth)
Ex, Cab
1.1 MHz
DMT 256
DMT 32/64
20.5 dBm
RS/Trellis
Overlayed/Splitter
100 Mbps
100 Mbps
3...12 kFt
Eth, (ATM)
Ex, Cab, Bl.
30 MHz
DMT 4096
DMT 4096
20.5 dBm
RS/Trellis
Overlayed/ Splitter
VDSL2
5.7 Mbps
5.7 Mbps
24 kFt
Eth,ATM,TDM
Ex
1.4 MHz
PAM 16/32
PAM 16/32
14.5 dBm
Trellis
Inband
SHDSL ADSL2+
28 Mbps
1~3 Mbps
12…20 kFt
ATM(Eth)
Ex, Cab
2.2 MHz
DMT 512
DMT 32/64
20.5 dBm
RS/Trellis
Overlayed/Splitter
Page 9Copyright © Infineon Technologies 2008. All rights reserved. 2009/09/29
Insertion loss of Twisted-Pair Cable
0 1 2-60
-50
-40
-30
-20
-10
0
f / MHz
dB
0 5 10 15 20 25 30-120
-100
-80
-60
-40
-20
0TP100 (-) TP1 (- -)
f / MHz
dB
0.2 km0.5 km1.0 km1.5 km2.0 km
kmMHzdB 18),(aTP100
lflf ⋅⋅≈
Cable: AWG-26 (0.4 mm)
Page 102009/09/29 Copyright © Infineon Technologies 2008. All rights reserved.
VDSL2 Downstream PerformanceMbps 8b=998-M2xB, 17a=998-M2xB+DS 12…17MHz
8b DS WN17a DS WN8b DS 12 Self17a DS 12 Self
500m 1000m
2000m
8,4Mbps
160,00
140,00
120,00
100,00
80,00
60,0050MBit/s
40,00
24MBit/s20,00
0,002743 m305 610 914 1219 1524 1829 2133 24380
AWGN @ -140 dBm/Hz
Page 112009/09/29 Copyright © Infineon Technologies 2008. All rights reserved.
VDSL2 Upstream PerformanceMbps 8b=998-M2xB, 17a=998-M2xB+DS 12…17MHz
305 610 914 1219 1524 1829 2133 2438 2743 m
20,00
40,00
8b US WN17a US WN8b US 12 Self17a US 12 Self
500m
20MBit/s
1000m
2000m
0,75Mbps
70,00
60,00
50,00
30,00
6MBit/s 10,00
0,000
AWGN @ -140 dBm/Hz
Page 12Copyright © Infineon Technologies 2008. All rights reserved. 2009/09/29
xDSL Deployment Scenarios
CentralOffice
F/O FeedDSLAM
Residential
Business
Residential
ONTF/O
FTTC
F/O
Business / Residential /
MxU
Cabinet Residential
ONU
F/O
ONT
F/O
NT
NT
MxU
FTTB
FTTCab
FTTEx
VDSL2
xDSL
xDSL
VDSL2
Page 13Copyright © Infineon Technologies 2008. All rights reserved. 2009/09/29
Down 1 Up 1 Down 2 Up 2Up
0ADSL
ADSL2+
Down / UpDown 2
25 138 3000 5100 12000
f (kHz)
30000
-60
-50
-40
Deployment from Cabinet / MDU
Deployment from Exchange/ Cabinet/ FTTN
7050 880
PS
D (d
Bm
/Hz)
ADSL / VDSL2 Transmit PSD VDSL2
Profile 12 ProfilVDSL2
e 17VDSL2
Profile 30VDSL2 � Profile 8
176000
" All DMT based xDSL flavours use Frequency Division Duplexing
" VDSL2 uses several profiles depending on deployment scenario
Page 142009/09/29 Copyright © Infineon Technologies 2008. All rights reserved.
Mixed Deployment Central Office / Cabinet
For the ADSL service, VDSL2 looks like „just another ADSL“► powerful PSD Shaping in 138kHz...2.2MHz range► crosstalk of VDSL2 = crosstalk of ADSL
+⋅+−≤
)()(
1log10)()()( 10refdist
refmainmainADSLDPBO fa
fafafPSDfPSD
�boost mode�
ADSL Data Rates not affected by VDSL2 deployment
VDSLCabinet
VDSLCPE
ADSLCPE
ADSLCO
USDS
2.2MHz 2.2MHz
DSUS
2.2MHz
DSUS
FEXT
2.2MHz
US DS
2.2MHz
US
Page 15Copyright © Infineon Technologies 2008. All rights reserved. 2009/09/29
Reference System: 72 Channel ADSL2+ IP-DSLAM
Digital Frontend
PCB layers: 8No. of components: 4470 No. of pins: 24176No. of nets: 4237No. of through holes: 5734Min. trace width: 120 umTotal trace length: 192.6 m
Network Processor
Analog Frontend
Page 16Copyright © Infineon Technologies 2008. All rights reserved. 2009/09/29
Datarate Increase: Vectoring
Page 17Copyright © Infineon Technologies 2008. All rights reserved. 2009/09/29
Scenario
" Telephone lines are deployed in large cable bundles
" Crosstalk is the dominant noise source in most deployment scenarios
" Crosstalk can be distinguished:
# NEXT – Near End Crosstalk
# FEXT – Far End Crosstalk
# Self and Alien Crosstalk
Page 18Copyright © Infineon Technologies 2008. All rights reserved. 2009/09/29
Measured Crosstalk Channel
104
105
106
107
-160
-140
-120
-100
-80
-60
-40
-20
0Measured single channel and crosstalk channel transfer functions
f [Hz]
|Hij|2 [d
B]
Direct channel |Hii|2
104
105
106
107
-160
-140
-120
-100
-80
-60
-40
-20
0Measured single channel and crosstalk channel transfer functions
f [Hz]
|Hij|2 [d
B]
Direct channel |Hii|2
17.6 MHz
Crosstalk channels |Hij|2, ≠i j
Parameter:
Number of cables: 20Cable length: 1 kmDiameter: 0.4 mm
FEXT is the dominant crosstalk for ADSL and VDSL2 systems
Page 19Copyright © Infineon Technologies 2008. All rights reserved. 2009/09/29
common processing of several lines with the purpose of cancelling self-crosstalk
Definition:
1. NEXT Avoidance
# VDSL2 uses Frequency Division Duplexing
# Synchronized Digital Duplexing (same Cyclic Extension, Clock, Timing Advance and DMT symbolstart for all lines in a loop)
2. FEXT Cancellation:
# estimation of FEXT channels; single pointof processing for all channels required
# upstream: CO-only realization; cancellation
# downstream: communication of error information from CPE to CO; pre-distortion
Two-step Approach:
Vectoring – Basic Principles
Page 20Copyright © Infineon Technologies 2008. All rights reserved. 2009/09/29
Infineon Vectoring Solution
" Data is passed in the frequency domain (before IFFT) to the Vector Engine
" FEXT Precoder performs linear precoding
" In upstream, data is passed after the FFT to the Vector Engine
" Vinax Data Frontend (DFE) performs VDSL2 Processing
" Vectoring Engine performs Crosstalk-Cancellation
" Control- / Synchronization split between Vectoring Engine / Vinax
" Maximum Number of Lines only limited by Vectoring Engine
Vectoring Engine
Highspeed IF
Highspeed IF
VINAX Rev. 2/3
Highspeed IF
VINAX DFE
Analog Frontend / LineSystem
Interface(Backplane)
Mapper #0
FEXTPrecoder
IFFT #0
IFFT #1
IFFT #N
Mapper #1
Mapper #N
Vector Engine
VINAXDatapump
VINAXDatapump
Vectoring Solution: System Partioning:
Page 21Copyright © Infineon Technologies 2008. All rights reserved. 2009/09/29
Infineon Vectoring Solution (Demonstrator)
DSP Module
Vectoring EvaluationBoard
Vectoring Adapter Board Rev1.3
Vectoring Controller Board with FPGA
Demonstration System based on actual IFX VDSL2 Chipset available
Page 22Copyright © Infineon Technologies 2008. All rights reserved. 2009/09/29
Performance – Downstream Measurement
" 16 Channel Vector System @ 300m
" Datarates:
# single line: 103.9 Mbit/s
# Vectoring: 100.8 Mbit/s
# w/o Vectoring: 47.9 Mbit/s
0 500 1000 1500 2000 2500 3000 3500 4000 45000
10
20
30
40
50
60
70SNR Plot - Line # 5
SN
R [d
B]
Toneindex
single linewith Vectoringw/o Vectoring
Datarate improvement of more than 100% achievable
Page 23Copyright © Infineon Technologies 2008. All rights reserved. 2009/09/29
Performance – Upstream Measurements Average SNR improvement over all used carriers
0
5
10
15
20
25
1 2 3 4 5 6 7 8 9 10 11 12Channel
dB
Test Conditions:
" 12 VDSL2 channels in Showtime
" VDSL2, Profile 17a + US0
" 150m PE0.35 cable @ DTAG Labs
Datarate improvement over all used carriers
0
10
20
30
40
50
60
70
1 2 3 4 5 6 7 8 9 10 11 12Channel
data
rate
[Mbp
s]
with DSMw/o DSM
US SNR measurements, 150m, 0.35mm
0
10
20
30
40
50
60
0 5 000 10 000Carrier [kHz]
SNR
[dB
]
Ch1 of 12 Ch with DSMCh1 of 12 Ch w/o DSMCh1 only
Page 24Copyright © Infineon Technologies 2008. All rights reserved. 2009/09/29
Standardization
" Consent for ITU Standard g.vector is planned for next week
" Comment resolution of standard will require some more month –expected publication: Spring / Summer 2010
Status:
" Crosstalk estimation based on pilot symbol sequences
" Joining Procedure:
# Allows seamless joining of new line to an active vectoring group
" Backchannel Definition:
# Quantized slicer errors of pilot symbols are reported from CPE to CO
Major Agreements:
Page 25Copyright © Infineon Technologies 2008. All rights reserved. 2009/09/29
Challenges for commercial deployments …
" Cable bundles consists of 100 to 500 lines – depending on operator / deployment scenario
" Operator are not able to sort lines according to crosstalk
" Lines are connected to several linecards – data needs to be exchanged between linecards
" Alien crosstalk or non-vectored systems will reduce performance increase
Network Topology:Coefficient Memory Size (Profile 17)
0,00
100,00
200,00
300,00
400,00
500,00
600,00
16 32 48 64 80 96 192
Number of Lines
Coef
ficie
nt M
emor
y [M
Byt
es]
MAC Operations
0
100
200
300
400
500
600
700
16 32 48 64 80 96 192
Number of Lines
GM
ACs " Required computational and memory
resources increase quadratic with the number of supported lines
" Coefficient memory size and memory access becomes the main bottleneck of an architecture
Complexity:
Page 26Copyright © Infineon Technologies 2008. All rights reserved. 2009/09/29
Smoothness of Crosstalk Coefficients
" Crosstalk Coefficients are slowly changing (“smooth”) over frequency
" Smoothness will be utilized for large vectored systems:
# Coefficient Memory:
Storing coefficient matrices for every nth carrier - other coefficient matrices will be interpolated
# Backchannel:
Slicer error values are only reported for every nth carrier
" Utilizing smoothness makes systems for more than 100 lines realistic
0 2 4 6 8 10 12 14 16-1
-0.8
-0.6
-0.4
-0.2
0
0.2
0.4
0.6
0.8
1Crosstalk Coefficients (Victim #0, Disturber #1)
Frequency [MHz]
Nor
mal
ized
Am
plitu
de
real partimaginary part
Page 27Copyright © Infineon Technologies 2008. All rights reserved. 2009/09/29
Robustness Increase: Virtual Noise / Retransmission
Page 28Copyright © Infineon Technologies 2008. All rights reserved. 2009/09/29
Triple-Play Requirements for DSL
" Video / IPTV
# High Data Rate (e.g. HDTV); always guaranteed
# Low Packet-Loss, < 1 / hour
# Small Error Rate
# No retrains
" VoIP
# Low Rate; always guaranteed
# Low Jitter, Low Delay
# No retrains
" Internet Access
# High Data Rate (variable rate acceptable)
# Low to medium delay (gaming)
Video and VoIP applications require higher robustness of the DSL link
Page 29Copyright © Infineon Technologies 2008. All rights reserved. 2009/09/29
Noise Sources" Stationary Noise
# Background Noise
# Crosstalk
" Radio Frequency
Ingress
# AM / Ham Radio ingress
" Impulse Noise
# SHINE – Single High Impulse Noise Event (up to 10 ms):
# REIN – Repetitive Impulse Noise:Impulse Length Inter Arrival Time
protection by „Virtual Noise“
protection by „Retransmission“
Page 30Copyright © Infineon Technologies 2008. All rights reserved. 2009/09/29
Virtual Noise – Basic Idea …
SNR for Bitloading
Noise margin
Background Noise
Tx
Rx
Loop Attenuation
Frequency
Pow
er S
pect
ral D
ensi
ty
Starting Point:Static Noise
SNR for Bitloading
Noise margin
Tx
Rx
Loop Attenuation
Frequency
Pow
er S
pect
ral D
ensi
ty
Background Noise
Dynamic Noiseleading to Retrain
Dynamic Noise (RFI, �)
Frequency
SNR for Bitloading
Noise margin
Tx
Rx
Loop Attenuation
Pow
er S
pect
ral D
ensi
ty
VirtualNoise
Virtual Noise
Background Noise
Dynamic Noise (RFI, �)
Virtual Noise corresponds to frequency specific SNR Margin
Page 31Copyright © Infineon Technologies 2008. All rights reserved. 2009/09/29
Retransmission – basic idea …
¬ Retransmission: another tool for combating infrequent and long impulse noise (SHINE and PEIN)
CO Modem CPE Modem
Buffer-Size determined by► Data-Rate► Round-Trip Delay► Desired Level of Protection
Page 32Copyright © Infineon Technologies 2008. All rights reserved. 2009/09/29
Robustness Features of DSL Systems
11
10
9
8
7
6
5
4
3
2
1
#
complements interleaving/FEC for (REIN), SHINE, PEINRetransmission
Coexistance of VDSL2 and ADSL in same bundle; mixed CO-Cabinet deployments
Downstream PowerBack-Off (DPBO)
Similar Upstream-Rate for all CPEs regardless of loop length
Upstream PowerBack-Off (UPBO)
Mitigate RFI ingress and avoid egressRFI Notching and Mitigation
Change of Data-Rate and Framing / ILV parameters on-the fly as response to changing loop conditions
Online Reconfiguration (SRA...)
Survival of sudden noise without retrainSOS
Conservative bit-loading in expectation of future (virtual) noise sources
Virtual Noise
Doubles INP (alternatively: improves rate for same INP)Erasure Decoding
Better INP for higher Data-Rates/Delays, i.e.ADSL2+ 8ms, INP=16, 16 MBit/s
Extended Interleaving
Better INP for higher Data-Rates, i.e.ADSL2+ 8ms, INP=16, 11 MBit/s
Extended Framing
Forward Error Correction provides baseline INP, i.e. ADSL2+ 8ms, INP=16, 1.5 MBit/s
General Convolutional Interleaving + Reed Solomon Coding
BenefitMeasure
Page 34Copyright © Infineon Technologies 2008. All rights reserved. 2009/09/29
Line Testing Overview
" Possible Tests:
# Detection and Measurement of Foreign Voltages
# Detection of Unbalance about Earth (Resistive Fault to Ground/Battery, Bad isolation Resistance, Capacitive Unbalance)
# Detection of Nonlinear Elements (PPA, Receiver Offhook, xDSL Signature)
# Measurement behind a Splitter (e.g. Ringer Load)
" Applications:
# Test electrical characteristics of line
SELT (Single Ended Line Test) MELT (Metallic Line Test)
" Possible Tests:
# Loop length
# Attenuation
# Achievable Bitrate
# Bridge tap presence and localization
# Quiet Line Noise
# Crosstalk estimation
# RFI Analysis
" Applications:
# Loop pre-qualification (no CPE required)
Page 35Copyright © Infineon Technologies 2008. All rights reserved. 2009/09/29
Evolution towards Next Generations Networks
IntegratedMELT
" On-chip line testing is going to replace MELT test heads
" With the transition towards a single NGN network (PSTN substitution) MELT needs to test, diagnose and locate line impairments on pure DSL lines
" SELT in combination with MELT could complete the line testing & monitoring function
New Test Methodology
DSLAM
AggregationNetwork
Customer Premises
Splitter
CPE
Customer ServiceTest Server, Database and Expert System
TODAYTOMORROW
Local Loop
MDF
…MELT Test
Heads
Splitter
PSTN (Voice)
DIV #
CPE
+ SELT
Page 36Copyright © Infineon Technologies 2008. All rights reserved. 2009/09/29
Efficiency Improvements with New Line Testing
DSLAM
AggregationNetwork
Customer Premises
Customer ServiceTest Server, Database and Expert System
Local Loop
MELT
MDF CPE
TOMORROW
+ SELT
" Same procedure and accuracy in NGN to test, diagnose and locate line impairments
" One line testing for ADSL, VDSL, SHDSL & Voice
" Frequent and parallel testing possible
" Saves splitters, MELT test heads, CO/RT space
" Line testing & wetting with no DSL disturbance
" Reuse of expert system without changes to customer service operations
Benefit
Page 37Copyright © Infineon Technologies 2008. All rights reserved. 2009/09/29
IFX Integrated Line Testing for All Digital Loop
InfineonxDSLAFE Infineon
LD
LD
InfineonLD
LD
MELT
SELT&DELT
InfineonVINETICTM-LTCSmart SLIC®-T
Infineon
MU
X
xDSLAFE
xDSLDFE
Perfect solution in terms of cost, density and reliability
" MELT function will be performed by a chipset solution of a Smart SLIC with inbuilt multiplexer and a Line Test Controller (VINETIC-LTC)
" VINETIC-LTC is able to control up to 128 xDSL ports
" Full MELT capabilities, integrated with DSL on one card at low cost
" Depending on configuration several ports can be tested simultaneously
" One line testing API for ADSL, VDSL, SHDSL
" Wetting current parallel to DSL
" Line testing & wetting with no DSL disturbance
" No mechanical components (relays, switching matrix etc.)
" Minor density impact
Benefit
Page 39Copyright © Infineon Technologies 2008. All rights reserved. 2009/09/29
Motivation
" Increasing number of customers use DSL for “triple play”
" Consequences:
# Higher bandwidth needed to support new services
# “always-on” of equipment is required for some services
Customer:
" Telecom Italia:
# requires more than 2 TWh per year
# roughly 1% of Italia's energy demand
# 2nd largest energy consumer (next to Italian railway)
" European Union:
# expects consumption of 50 TWh in 2015 for Broadband Equipment (corresponds to four modern nuclear power plants)
Operator:
Reduction of power consumption has high priority for operator, system vendor, and chip industry
Page 40Copyright © Infineon Technologies 2008. All rights reserved. 2009/09/29
European Union – Code of Conduct
CoC Version from July 2007" Updated version of CoC
# Technical lead: Swisscom & TI
# Infineon actively involved and contributing
" Status
# in force (1.1.2009)
" References ETSI TS 102 533 for measurement conditions
V3 from
Nov 18th 2008
CoC V3 from 11/08, DSL-CO
Page 41Copyright © Infineon Technologies 2008. All rights reserved. 2009/09/29
Power Consumption
" Linedriver:
# Proper choic of amplifier class can reduce power consumption significantly
# ADSL (Source: Scott Wurcer, ADI):
¬ Class A/B: 710 mW
¬ Class G: 485 mW
¬ Class H: 410 mW
" Semiconductor Technology:
Producing chips in most advanced technology (45nm, 65nm instead of 90nm, 130nm)
" Other topics:
# A/D and D/A Converter
# Digital Filter (Highpass / Interpolation / Decimation) Concepts
Source: Huawei, ITU Contribution C832, Jan. 08
0
500
1000
1500
2000
2500
ADSL VDSL2, Profile 17 VDSL2, Profile 8
Pow
er C
onsu
mpt
ion
[mW
]
Datapump + AFE [mW]
Line Driver[mW]
Options for Power ReductionCoC V3
Limit 2011
Page 42Copyright © Infineon Technologies 2008. All rights reserved. 2009/09/29
Low Power Mode
" VDSL2 has no standardized low power mode
" ADSL low power mode is not widely used because of fluctuating crosstalk
Current Status:
" Several operator and chip manufacturer push for an efficient low power mode
" Debate ongoing about required standard changes and power saving potential of different options
Current Activities:
Page 432009/09/29 Copyright © Infineon Technologies 2008. All rights reserved.
DSL System – today …
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
IP-TVFile Download Internet
0.6 W
0.8 W
1.0 W
1.2 W
1.4 W
0 W
Constant Power-
Consumption regardless of
Traffic!
DATADATA DATADATA DATADATAIDLEIDLEIDLEIDLE
Signal:
Page 442009/09/29 Copyright © Infineon Technologies 2008. All rights reserved.
Vision …
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
IP-TV
DATADATA DATADATA DATADATAIDLEIDLEIDLEIDLEDATADATA DATADATA DATADATAIDLEIDLEIDLEIDLE
Signal:
File Download
Internet
0.6 W
0.8 W
1.0 W
1.2 W
1.4 W
0 W
Low Power Mode
Low PowerMode
Power-Consumption should adapt to Data Traffic!
Page 46Copyright © Infineon Technologies 2008. All rights reserved. 2009/09/29
Future Challenges for DSL Systems …
Line Management /
Testing
- MELT / SELT
Power Reduction Increased Stability
- Virtual Noise
- Retransmission
Increased Datarate
- Vectoring
… several challenges are addressed more innovations needed to fulfill all customer needs /
requirements