1. Broadband Over Power Line
Submitted By:
Veena Radhakrishnan
S7 CSE

2. Outline Of The Presentation.
What is Broad Band Access?
Introduction to BPL.
History of BPL
How Does it Works?
BPL Modems.
Method Of Transmission- OFDM
Types of BPL
Comparison with other technologies.
Limitation
Current Status
Future Scope.

3. What is BroadBand Access?

4. What is BroadBand Access?
High Speed Access to Internet.
Greater than 128Kbps.
Always ON!
Simultaneous up-link and down-link communication.
Made possible by digital modems.
Leading BroadBand Technologies:
xDSL, cable, satellite, ISDN digital modem,

5. INTRODUCTION TO BROADBAND OVER POWERLINES
Broadband alternative for homes & business.
Also known as power line carrier, mains communication, power line telecom (PLT), or power line networking (PLN).
Requires no cabling or infrastructure.
Cost and speed.
Only equipment required: Special modem plugged into electrical receptacle.

6. BRIEF HISTORY OF BPL. PLC has been around for quite sometime.
BPL began at the end of 1990.
The first technique to make use of the power line for control messages was the method - Ripple Control ( Hz,10KW)
1950: at a frequency of 10Hz, 10kW of power, one-way: town lighting, relay remote control.
Mid 1980s: beginning of research into the use of the electrical grid to support data transmission, on bands between Khz, always in a one-way direction .
1997: first tests for bidirectional data signal transmission over the electrical supply network and the beginning of research by Ascom (Switzerland) and Norweb (U.K.)
2000: first tests carried out in France by EDF R&D and Ascom

7. ENABLING TECHNOLOGY Advanced methods for modulating data signals.
Faster Chip set.
Digital equipments to amplify signals.
Equipments to send or bypass signal through transformers.

8. HOW STUFF WORKS ??
Delta
This is the general conceptual arrangement. An Injector serves to provide the main data signal, a Repeater serves to boost the signal at regular intervals due to line noise (similar to Telephone T1 provisions), and an injector r=serves to convey the data across the power transformer to the user(s) as each transformer may feed power to several customers, even though only one may desire the BPL signal.

10. CT COUPLER: CT BRIDGE: BACKHAUL POINT: CT VIEW MANAGEMENT SYSTEM:
routes and controls data traffic between the low and medium-voltage lines.
CT COUPLER:
Couples BPL signal to medium voltage primary lines.
BACKHAUL POINT:
CT VIEW MANAGEMENT SYSTEM:
Network management system that monitors and controls the BPL system.

12. BPL MODEM Use specially designed Silicon Chips.
Capable of handling PowerLine Noise- through use of specially developed modulation technique & adaptive algorithm.
roughly the size of a common
power adapter.
It plugs into a common wall socket.
Ethernet cable running to computer finishes the connection. Wireless versions are also available.

14. Most commonly used Modulation Technique.
METHOD OF TRANSMISSION-OFDM(ORTHOGONAL FREQUENCY DIVISION MULTIPLEXING)
Most commonly used Modulation Technique.
Another technology used is CDMA.
Also called Discrete Multitone Modulation (DMT), is a transmission technique based upon the idea of frequency division multiplexing (FDM) (used in IEEE a).
Comparison to FDM:
Coupling with "Channel Coding“:
almost always used in conjunction with channel coding- an error correction technique, to create coded orthogonal FDM or COFDM .

15. OFDM Contd….. Benefits & Usage: Disadvantages of OFDM:
high spectrum efficiency, resistance against multipath interference (particularly in wireless communications), and ease of filtering out noise .
has high performance.
By combining the OFDM technique with error-correcting codes, adaptive equalization and reconfigurable modulation,
Disadvantages of OFDM:
suffers from time-variations in the channel, or presence of a carrier frequency offset.
tends to have a high peak-to-average power ratio (PAPR)
it is necessary to minimize intermodulation between the sub carriers, which would effectively raise the noise floor both in-channel and out of channel. For this reason circuitry must be very linear

16. TYPES OF BPL
Access BPL.
Utilize the power distribution network, owned, operated and controlled by an electricity service provider.
Use injectors, repeaters and extractors to deliver high-speed broadband services to the end-user.

17. Types Contd.. 2. In-House BPL
Network machines within the building.
Utilize electric power lines not owned, operated or controlled by an electricity service provider, such as the electric wiring in a privately owned building.
Devices are connected to the in-building wiring and use electrical sockets as access points.
designed to provide short-distance communication solutions
Product applications include networking and sharing common resources such as printers.

18. ACCESS BPL
IN HOUSE BPL

19. ISDN Cable Modem DSL BPL
COMPARISON OF POWER LINE COMMUNICATIONS AND OTHER RELEVANT TECHNOLOGIES
ISDN
Cable
Modem
DSL
BPL
Transmission media
Twisted pair
Co axial
Electric lines
Connection
Dedicated
Shared
Availability
On demand
If cable present
Users close to end office
Also available to rural customers
Capacity
128Kbps
100 times greater than twisted pair
1MbpsDownstream19
256KbpsUp stream
45Mbps

20. TECHNICAL CHALLENGES Unpredictable Noise Levels on Power Line.
Attenuation Problem.
Attenuation Problem at Distribution Transformer.
Potentially harmful Radio Frequency interference (RFI).
High Voltage and Fluctuation corrupt Data.
Distribution System.

21. LIMITATIONS
Distances: distance between the customers home& supplying sub-station is a factor in the bit rate available to the user.
Equipment :avg transformer will’t allow the radio frequencies to pass through.
Cost: high capacity back bones.
Competition: Competition from providers such as DSL and Cable ISPs
Security: power lines produce a fair amount of EMI (Electro Magnetic Interference).
Government Regulation :regulations for the use of certain technologies that produce EMI

22. Where Are We Today? 12 – 15 Field tests across the U.S. (At least).
No common standard (Yet!).
City of Manassas first commercial deployment followed by Cinergy.
FCC working on revised rules.
But industry can deploy under existing rules.
Huge potential for last mile broadband service.
Need for more investment dollars and partners.

23. CURRENT STATUS CONTD.. BPL in IRELAND Govt supporting a trail of BPL.
The trials are set to take place in Tuam, Co. Galway with the help from the ESB.
The trials are set to commence in the next few months with homes, schools and businesses connected to the Internet by way of ESB power lines (PLC).

24. CONTD… BPL in US. FCC to measure interference.
FEMA & ARRl expressed concern over unlicensed BPL equipment interfacing with their licensed radio signals.
FCC sees BPL as a potential competitor to DSL.
Current technologies provide BPL to Cincinnati &Rockville, MaryLand
CURRENT Technology- Home Plug -no interference with radio signals
Other ISPs- Earth Link -to test BPL leased from Progress Energy

25. What Needs to Happen Next??
Need for franchise & financial partnerships
Electric Utility Executives must commit to enterprise models & actively support projects
Current roll-outs needs to better publicized
Need for “business certainty” environment

26. FUTURE OF BPL…
Following factors determine whether BPL will succeed in broadband market:
Standardisation of BPL technology.
Cost of BPL.
Interference issues needs.
The marketing of BPL needs to be performed to a high standard.

27. REFERENCE www.nwc.com www.currenttechnologie.com

28. THANK YOU