Broadband Developments
ISPLC 2005
PCSRG 2005 ISPLC2005
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PLC Generic Model
Backhaul
network
High
Voltage
Xmission
Equipment
pt to multi-pt
CPE
Phone(s)
pt to pt
Fibre
Network
PC
Internet
Medium Voltage Grid
(“Last Mile”)
Low Voltage
(“Last 100m”)
In-Premise
(“Last Inch”)
* CPE - Customer Premise Equipment
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Current Trends: Computing
is ubiquitous and the world
is networked
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Everywhere, There’s Exploding Demand for
Communications Bandwidth
Global Internet
Users
Worldwide Access
Lines
250M
2B
Wireline
Wireless
Cable
1B
1918
1938
1958
1978
1998
Internet Session
20 - 30 minutes
134M
30M
1898
Changing
Traffic Patterns
2018
1994 1998 2001
Voice Call
3 minutes
Average Hold Times
 It
took about a century to install the world’s first 700 million
phone lines
 More than 100 million additional Internet users
will come on-line in 2001
Jen
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Technology
Accelerators
Doubling Time
(months)
9 12
1
Optical Fiber
(bits per second)
18
Silicon computer Chips
Data Storage
(number of transistors)
(bits per square inch)
2
3
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5
5
An Upward Bandwidth Spiral
1800
Costs
Dropping
Bandwidth
Increasing
Applications
Growing
Total % Increase
1600
1400
1200
1000
800
600
400
200
0
1995
1996
1997
1998
1999
2000
2005
Network Traffic (US)
jen
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Broadband Access Market
Broadband Connections by Nation/Technology
At-home Internet users
Nation
T1/
Total
Prediction
Leased
Broadband
2005
Line
Cable Satellite
ADSL
Korea
18.6%
0.1%
38.6%
0
57.3%
U.S.
7.6%
0.5%
2.8%
0.2%
11.1%
Hong
Kong
6.0%
0.9%
1.2%
0
8.13%
Singapore
6.6%
n/a
0.5%
0
7.1%
Taiwan
3.5%
0.1%
2.6%
0
6.2%
France
4.0%
0.3%
1.7%
0
6.0%
Denmark
3.4%
0.0%
2.4%
0
5.8%
Germany
2.7%
0.1%
2.2%
0
5.0%
27.4%
Spain
1.8%
0.2%
1.1%
0
3.1%
21.9%
U.K.
2.3%
0.3%
0.5%
0
3.1%
19.5%
China
0.2%
n/a
0.2%
0
0.4%
53.1%
22.6%
Source: NetValue Prediction: Strategy Analyrics
Internet Penetration (source: NetValue)
Broadband Percentages of Total Penetration
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Commercial Status
SENER
ELFORSK, VATENFALL
NUON
PATTERN
•US
Activities
MVV , PPC
EDF
UNION FENOSA
ENEL
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Worldwide PLC Activities
Island:
LinaNet
Reykjavik Energy
Indianapolis, Boston
Norwegen:
Stadtwerke Bergen
Schweden:
Sydkraft, BirkaEnergi
Finnland – EVU-Verband
China
Provinz Sechuan
UK/SSE
Spanien
Endessa
Portugal
EdP
Italien
Enel
Brasilien:
Copel
Cemig
InfoPaolo
D – RWE, EnBW, MVV, oneline
A - TIWAG, EVN, Stw. Salzburg, EVO
CH - DIAX
Korea
Keyin
Kuwait
ITS
Qatar
Israel
Mainnet,
ITRAN,
Malaysia
elLine
FibreCom
Multimedia-Ministerium
Südafrika
(Siemens)
Argentinien
(ascom)
Chile
(Endesa)
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Pictures ‘PLC around the World’
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Opportunities for Power
Utilities as
Communications
Bandwidth Suppliers
Three broad domains of opportunity



As backbone bandwidth wholesalers
As distribution network “last mile”suppliers
As in-building network suppliers
More than 100Electric Utilities authorized as
Telecom Carriers
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Broadband Access Options
100
Wireless (Time-Space
Processing)
VDSL
Cable
Modem
Bandwidth
10
Wireless
(steerable beam)
ADSL
DSL-Lite
1
Fixed Wireless
(stationary beam)
ISDN
0.1
56K
33.6
28.8
0.01
1988
VF Modem
14.4
1990
1992
1994
1996
1998
2000
2002
2004
2006
Deployment Year
Jen
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Broadband Local Distribution
Technologies: Today’s Contender’s
DSL
Cable
Modems
Fixed
Wireless
(2.4GHz)
Satellite
Cost/mo. Avg.
$60
$45
$145
$65
Installation
Avg.
$30
$250
$1250
$400
Est.
Subscribers
2M
3.4M
140K
750K
Projected
Subs. 2005
12M
14M
1.5M
2.4M
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Standard Communication
characteristics
• Unique frequency specification
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Standard Communication
characteristics
• Unique frequency specification
• Characteristic impedance
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Standard Communication
characteristics
• Unique frequency specification
• Characteristic impedance
• Minimum noise
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Standard Communication
characteristics
• Unique frequency specification
• Characteristic impedance
• Minimum noise
• Constant bandwidth
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Standard Communication
characteristics
• Unique frequency specification
• Characteristic impedance
• Minimum noise
• Constant bandwidth
PCSRG 2005 ISPLC2005
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Standard Communication
characteristics
• Unique frequency specification
• Characteristic impedance
• Minimum noise
• Constant bandwidth
• Standard architecture
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Standard Communication
characteristics
• Unique frequency specification
• Characteristic impedance
• Minimum noise
• Constant bandwidth
• Standard architecture
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Standard Communication
characteristics
• Unique frequency specification
• Characteristic impedance
• Minimum noise
• Constant bandwidth
• Standard architecture
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Leaky cables @1Mhz to 30Mhz
• At these frequencies not all the signal is
transmitted down the cable-it leaks power
• So some of the high frequency signal
emanates as electromagnetic radiation
• Hence power cables can be considered as
linear antennas and
• Low efficiency
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Coupling via the Mains Network
LN
50Ω
50µH
Source
Victim
Attenuation, dB/30m
30
20
10
Distribution network
Mains only
0.1
1
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Frequency MHz
24
Radiated emission
Mains cable
Mains cable
Equip1
Conducted emission
through mains
plc1
Conductio through
earth impedance
Radiated emission cable to cable
Mains
cable
Mains cable
Radiated emission case to case
plc2
External mains interference
Electromagnetic radiated emission
and coupling Interference
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Physical structure
of LV network
Armoured Cable
• Underground & overhead distribution
• Armoured cable
• Conditioning units (CU) may be used
Conditioning Unit (CU)
MV
network
Network
LV network
CU
SUBSTATION
Data
network
Internal
mains
network
LV network
CU
Data port
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Frequency Bands
General Frequency Bands
• 1.6MHz to 30MHz
• Division :Access band 1.6MHz-10MHz
• In-house band 10MHz to 30MHz
• USA variation and extension for Overhead
systems
• Access: 10MHz -80MHz
• In-house: 1.6MHz to 10MHz
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Spectrum & Technologies
30 kHz
300 kHz
3 MHz
MEDIUM
FREQUENCY
LOW FREQUENCY
30 MHz
HIGH FREQUENCY
GROUND WAVE
SKY WAVE
SPACE WAVE
ADSL 25 kHz - 1.1 MHz
VDSL 1.1 - 30 MHz
DPL 1.1 - 30 MHz
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Scope
IONOSPHERE
SKY WAVE
3 - 30MHz
SPACE WAVE
0.1 - 30MHz
Q
GROUND WAVE
0.1 - 3MHz
LONDON
NEAR FIELD
SUBURBAN
RURAL
ROME
G
Average UK ground
0 km
5 km
200 km
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1500 km
29
Established Communication
Services in the 1MHz to 30MHz
•Broadcasting Channels
•Amateur Radio
•Mobile Communications
•Distress frequencies
•Military communications
•Radio astronomy
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Regulatory Landscape for
PLT
ITU
IEC
CISPR
Inter Governmental
organisations
European
Commission
CENELEC
European
Parliament
National Standards
Organisations
CIGRE
IEEE
ETSI
Government
Regulators
Industry
Associations
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IEEE Standards Board -PLT
Committee Structure
• Power Engineering Society
• Communications Society
• Electromagnetic Compatibility Society
• Antennas and Propagation Society
• All are welcome
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Sources of Interference
• Noise caused by impedance mismatch
• Impulse noise ingress from electrical
appliances
• Narrow band ingress from SW broadcast
• Attenuation of the network
• impedance variations
• general interference
• poor power quality
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The problem
• we measure E or H fields at some distance
from a source, but need to know the field
strength value at some other distance
• it is often assumed that fields vary with
distance as 1/r , 1/r2,1/r3,1/r n
– when is this right?
• magnetic field H from infinite straight wire
carrying steady (DC) current does indeed
vary as 1/r
– but our wires are finite in length, and aren’t
carrying DC
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What about real-size, finite dipole?
• for simplicity, most text books derive only far
field for practical antennas, by integrating just
the 1/r terms
• Jordan & Balmain (“Electromagnetic Waves &
Radiating Systems”) do the full solution
(including near-field terms) for arbitrary length
dipole- assumes usual sinusoidal current
distribution
• special case if dipole is half wavelength (or odd
multiple)
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Regulation for Radio
Service Protection
Main goal: Protection of radio services by
 Define radiation limits.
 Same limits for all telecom-products (e.g. xDLS, ISDN, PLC,…)
 Measurement method for in situ measurements
Hence, requirements for new telecommunication equipment are more
stringent than for other equipment (e.g. LAN..)
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Mitigation Methods
• In case of interference complaint, several
actions can be done by the operator:
–Introduce second injection point
–Apply Notches
• Before that – the regulator will evaluate that:
–The complaint by the user is justified
–The user has done all possible to
eliminate the complaint
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Spectral Characteristics of
modern Telecommunications Signals
• Modern telecommunications technologies are digital
technologies.
• OFDM technologies are the majority, but some other
multi-carrier technologies and some spread-spectrum
single-carrier technologies also exist.
• These technologies can be designed in such a way,
that
– the carrier spacing of an OFDM system is much
higher than 10 kHz, and each carrier is modulated
by randomized modulation (e. g. QAM)
– the channel bandwidth of multi-carrier
technologies is very much higher than 10 kHz
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Developments towards the PLT
Standard
• Coexistence between Broadband PLT and Wireless
•
•
•
communications services
Broadband may be assessed as a communication service
causing intentional or unintentional radiation
Intentional radiators use EM waves as a carrier of
information typical of wireless telecommunications
services-Licensing required
An unintentional radiator is primarily a wire-bound
service that generates radiated emission as a secondary
unwanted by-product –Broadband PLT should be treated
as a unintentional radiator wire-line service with
radiated emission treated as a parasitic undesirable
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Broadband PLT And EMC Limits
• If Broadband PLT is unintentional radiator it is
•
•
•
subject to EMC Limits
Two basic EMC StandardsIEC CISPR developed by International
committee’s and generally adopted as national
law
If the laws are not adopted, national regulatory
bodies provide their own legislation
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CISPR 22
• Conducted limits for products:
• Wire-line systems which are:
• DSL systems
• Cable modem systems and
• Broadband PLT systems
• The same standard applies to all three
systems
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IEC CISPR 22 and Broadband PLT
• Broadband PLT requirements close to CISPR22
• CISPR22 specifies limits for information
•
•
•
technology equipment (ITE) and distinguishes
between :
Mains Ports-power supply ports and
Communication ports
However PLT operates with a single port for
mains and data communications- Multipurpose
Port
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Interference Potential of a Port
According to CISPR22
• CISPR22 covers DSL and Cable modem
services
• CISPR22 charter was modified to include
PLT Broadband services and the multipurpose port
• This is a product standard
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CISPR22 Interference potential
assessment
• The interference potential is assessed by connecting the port of the
equipment under investigation to an “Artificial Network” which
represents the real World as closely as possible
• For the telecommunications port a T-shaped impedance stabilization
network known as a T-ISN represents the artificial Network
• For the mains port a V-shaped ISN is used to represent the Artificial
network (V-ISN)
• Measurements based on the T-ISN delivers the asymmetrical voltage
, Uasym which represents the disturbance potential of the
communicating signal
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Limits for Mains and Tele-com Ports
Frequency MHz Mains Port (VISN) QP/dB
(uV)
0.15-0.5
66-56
Telecomm Port
(TISN)QP/dB(uV)
84-74
0.5-5
56
74
5-30
60
74
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Development of M313
• CISPR22 is a product (device) standard
• M313 mandate covers the complete network which
•
•
•
•
means the actual power lines
Also this new law will cover only complaints of
interference
This however does mean that modems causing
interference may be made to be switched off if it is
causing interference to established radio services
The eventual outcome will be a harmonised European
standard
Current proposals from EU countries are wide ranging PCSRG 2005 ISPLC2005
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Radiated
Emission Standard
Radiated
Emission
standard proposals in Europe
90.0
UK MPT1570 (Pk)
Equivalent Electric Field [dBuV/m @ 3m]
80.0
EN55022 Class B (QPk)
(Derived below 30MHz, Pk above 1GHz)
70.0
German NB30 (Pk)
60.0
Norwegian Proposal (Pk)
50.0
PLC Proposal (QPk)
(Derived from FCC limits using 33dB/dec)
40.0
Guelleman Limit (QPk)
30.0
BBC Proposal (Pk)
20.0
10.0
0.0
-10.0
0.01
0.1
1
10
Frequency [MHz]
100
1000
10000
- For comparison purposes limits scaled to 3m using 20dB/dec except PLC proposal 33dB/dec
- For EN55022 the magnetic field is calculated from the telecom port common mode current limit using:
H = I / 2.pi.r where r = 3m
- H-field limits converted to E-field using the far field correction of 51.5 dB
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Summary
• Limits for radiation are still under
•
discussion - EC granted a mandate313 to
ETSI/CENELEC/CEN to develop European
harmonized standard
Main considerations:
– Balance with existing radiation
caused by other systems e.g. LANs
etc.
– Balance should be made between
the protection of the Spectrum and
the introduction of new technologies
and their national economic benefits
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Near and Far Field Radiated Impedance Measurements
10K
Wave
impedance
Ω
Z=(μ/є)½
Electric Field predominates:low current,high voltage radiator
Far Field
1K
Near Field
377
Plane Wave Z=377Ώ
Wave Impedance=E/H
High current,low voltage,low
impedance
100
Magnetic Field
predominates
d<λ/2Π
d >λ/2Π
1
Distance metres
D=λ/2Π
PCSRG 2005 ISPLC2005
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160
140
120
see legend
100
LCL (dB)
impedance (ohms)
80
60
40
20
0
2
2.4
4.8
5.3
7.5
8.3
8.4
10
12.4
15
15.4
18
18.4
21.4
24.5
25.5
27.9
30
frequency (MHz)
PCSRG 2005 ISPLC2005
50
160
140
120
see legend
100
LCL (dB)
impedance (ohms)
80
60
40
20
0
2
2.4
4.8
5.3
7.5
8.3
8.4
10
12.4
15
15.4
18
18.4
21.4
24.5
25.5
27.9
30
frequency (MHz)
PCSRG 2005 ISPLC2005
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LCL and Impedance
Variation in the LCL and Impedance
• Variation in Impedance with LCL may be in phase
•
•
for the Kitchen
However the same relationship for the garage is
not so close
Measuring at different points in the same house
and same wiring does introduce errors leading to
variable LCL and Impedance
PCSRG 2005 ISPLC2005
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Emissions Normalised to 13m
emissions from PLC with 10dBm input
120
emission (dB microvolt/m
100
80
detached house
60
lamp post
house with skeletal wiring
40
20
0
2.3
2.9
4.95
5.42
6.9
8.9
10.9
13
frequency (MHz)
16.5
18.6
19.3
PCSRG 2005 ISPLC2005
20
25
29.5
53
PCSRG 2005 ISPLC2005
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Committee’s and standards to
Monitor
• EMC Directive 89/336/EEC
• General EEC IT committees
• Cenelec SC205A especially WG10-high
frequency committee
• TC210 Cenelec EMC committee
• ETSI PLT covers all broadband issues
• FCC15 for USA Broadband PLT
developments
PCSRG 2005 ISPLC2005
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Key Measurement Parameters
•
•
•
•
•
•
•
•
•
Noise floor for urban, semi-urban and rural
Conducted emission
Common mode emission and electric field
Longitudinal Conversion Loss-LCL
Impedance of line
K factor
Regression and
There inter-relationship in the near and far field
Relationship with single and three phase systems for
Ring Main and Tree& Branch wiring architecture
PCSRG 2005 ISPLC2005
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For Further Information
•
John Newbury
•
Power Communications Research
•
The Open University
•
Manchester , England
•
Tel 44 161 956 6857
• Email j.e.newbury@open.ac.uk
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