Broadband Over Power Line

Submitted By: Veena Radhakrishnan

S7 CSE

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.

What is BroadBand Access?

?

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,

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.

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 (100-900Hz,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 5 - 500Khz, 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

ENABLING TECHNOLOGY

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

transformers.

HOW STUFF WORKS ??

Delta

CT BRIDGE: 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.

Broadband Over Power Lines

BPL Injector / Repeater

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.

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 802.11a).

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 .

OFDM Contd….. Benefits & Usage:

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

TYPES OF BPL

1. 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.

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.

ACCESS BPLIN HOUSE BPL

COMPARISON OF POWER LINE COMMUNICATIONS AND OTHER RELEVANT

TECHNOLOGIES

ISDN CableModem

DSL BPL

Transmission media

Twisted pair Co axialCable

Twisted pair Electric lines

Connection

Dedicated Shared 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

1MbpsDownstream19256KbpsUp stream

45Mbps

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.

LIMITATIONS

Distances: distance between the customers home& supplying sub-

station is a factor in the bit rate available to the user. EqEquipmentuipment :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

Where Are We Today?

12 – 15 12 – 15 Field testsField tests across the U.S. (At least). across the U.S. (At least). No No common standardcommon standard (Yet!). (Yet!). City of Manassas first commercial deployment City of Manassas first commercial deployment

followed by Cinergy.followed by Cinergy. FCC working on FCC working on revised rulesrevised rules..

But industry can deploy under existing rules.But industry can deploy under existing rules. Huge potentialHuge potential for last mile broadband service. for last mile broadband service. Need for more Need for more investmentinvestment dollars and partners. dollars and partners.

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).

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

What Needs to Happen Next??

Need for franchise & financial partnershipsNeed for franchise & financial partnerships Electric Utility Executives must commit to Electric Utility Executives must commit to

enterprise models & actively support projectsenterprise models & actively support projects Current roll-outs needs to better publicizedCurrent roll-outs needs to better publicized Need for “business certainty” environmentNeed for “business certainty” environment

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.

REFERENCE

www.nwc.com www.currenttechnologie.com www.powerlinecommunication.com