Up Dated Powerline Communication Seminar Report1

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Seminar Report Powerline Communication 1.0.0 Introduction Connecting to the Internet is a fact of life for business, government, and most households. The lure of e-commerce, video on demand, and e-mail has brought 60 million people to the Internet. Once they get to the Internet, they find out what it’s really like. That includes long waits for popular sites, substantial waits for secure sites, and horrible video quality over the web. Telephone companies have offered high bandwidth lines for many years. For the most part, the cost of these lines and the equipment needed to access them has limited their usefulness to large businesses. The lone exception has been ISDN (Integrated Services Digital Network) which has won over some residential customers. ISDN offers fast Internet access (128k) at a relatively low cost. Dept. of EEE BMSCE, Bangalore 1

Transcript of Up Dated Powerline Communication Seminar Report1

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Seminar Report Powerline Communication

1.0.0 Introduction

Connecting to the Internet is a fact of life for business,

government, and most households. The lure of e-commerce, video on

demand, and e-mail has brought 60 million people to the Internet. Once

they get to the Internet, they find out what it’s really like. That includes

long waits for popular sites, substantial waits for secure sites, and horrible

video quality over the web.

Telephone companies have offered high bandwidth lines for

many years. For the most part, the cost of these lines and the equipment

needed to access them has limited their usefulness to large businesses. The

lone exception has been ISDN (Integrated Services Digital Network) which

has won over some residential customers. ISDN offers fast Internet access

(128k) at a relatively low cost.

Here the solution is Powerline communications (or PLC).

Powerline communications is a rapidly evolving market that utilizes

electricity power lines for the high-speed transmission of data and voice

services.

None of the available Internet access services offer the right

balance of cost, convenience, and speed. Digital Powerline technology

could change all that. It gives customers high speed Internet access through

electrical networks. Lower costs are achieved because the service is

implemented on standard electrical lines. The service is also convenient

Dept. of EEE BMSCE, Bangalore1

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Seminar Report Powerline Communicationbecause it’s already in your home. Internet access through Digital

Powerline would be at (at least) 1Mbps, 20 times faster than a standard

phone/modem connection.

1.1.0 History

The technology has roots going back to the 1940s.It has been

used by power utilities for simple telemetering and control of electrical

equipment in their networks.

What is new is the integration of activities outside the building

with those inside the building at a much higher bandwidth, 2.5 mbps or

higher.

1.2.0 Overview of Technology

PLC works by transmitting high frequency data signals

through the same power cable network used for carrying electricity power

to household users. Such signal cannot pass through a transformer. This

requires devices that combine the voice and data signals with the low-

voltage supply current in the local transformer stations. The signal makes

its way to neighborhoods and customers who could access either it

wirelessly, through utility poles.

Digital Powerline use a network, known as a High Frequency

Conditioned Power Network (HFCPN), to transmit data and electrical

signals. A HFCPN uses a series of Conditioning Units (CU) to filter those

Dept. of EEE BMSCE, Bangalore2

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Seminar Report Powerline Communicationseparate signals. The CU sends electricity to the outlets in the home and

data signals to a communication module or "service unit". The service unit

provides multiple channels for data, voice, etc. Base station servers at local

electricity substations connect to the Internet via fiber or broadband coaxial

cable. The end result is similar to a neighborhood local area network.

1.2.1 The Server

The Digital Powerline base station is a standard rack

mountable system designed specifically for current street electricity

cabinets. Typically, one street cabinet contains twelve base station units,

each capable of communicating over 1 of 40 possible radio channels. These

units connect to the public telecommunications network at E1 or T1 speeds

over some broadband service.

Several options, with different costs, can provide broadband

Internet service to each base station. The simplest solution is connecting

leased lines to each substation. This solution is potentially quite costly

because of the number of lines involved. A wireless system has also been

suggested to connect base stations to the Internet. This option reduces local

loop fees, but increases hardware costs. Another alternative involves

running high bandwidth lines, along side electric lines, to substations.

These lines could be fiber , ATM, or broadband coaxial cable. This option

avoids local loop fees, but is beset by equipment fees. The actual

deployment of Digital Powerline will probably involve a mix of these

alternatives, optimized for cost efficiency in different areas and with

different service providers.

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These base stations typically serve approximately 50

customers, providing over 20 MHz of usable spectrum to near end

customers and between 6 and 10 MHz of useable spectrum to far end

customers. The server operates via IP to create a LAN type environment for

each local service area.

1.2.2 The HFCPN Conditioning Unit

The conditioning Unit (CU) for the Digital Powerline Network

is placed near the electric meter at each customer’s home. The CU uses

band pass filters to segregate the electricity and data signals, which

facilitate the link between a customer’s premise and an electricity

substation.

The CU contains three coupling ports. The device receives

aggregate input from its Network Port (NP). This aggregate input passes

through a high pass filter. Filtering allows data signals to pass to a

Communications Distribution Port (CDP) and a low pass filter sends

electric signals to the Electricity Distribution Port (EDP).

The 50 Hz signal flows from the low pass filter, out of the

EDP and to the electricity meter. The low pass filter also serves to attenuate

extraneous noise generated by electrical appliances at the customer

premises. Left unconditioned, the aggregation of this extraneous noise from

multiple homes would cause significant distortion in the network.

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The high pass filter facilitates two way data traffic to and from

the customer premise. Data signals flow through the CDP to the customer’s

service unit via standard coaxial cable.

1.2.3 Service Unit

The service unit is a wall or table mountable multi-purpose

data communications box. The unit facilitates data connections via BNC

connectors to cable modems and telephone connections via standard line

termination jacks. The service unit provides its own line power for ringing

and contains a battery backup in case of power outage. Alternative

Differential Pulse Code Modulation (ADPCM) is used for speech

sampling. Because Digital Powerline allows for

the termination of multiple radio signals at the

customer premises, the service unit can

facilitate various Customer Premises Equipment

(CPE) simultaneously. In a manner similar to

ISDN, data (computers) and voice (telephones)

devices can coexist without interfering with

each other.

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1.3.0 CASE STUDY

1.3.1 Powerline Trials: Seymour Park Primary School

Digital Powerline

technology was

first tested in a

public setting at

the Seymour Park

Primary School in

Manchester, UK.

Twelve PCs were

connected to a

single Digital Powerline outlet. Dedicated high-speed access to the Internet

turned out to be a great success in the eyes of students and teachers.

Nortel’s Digital Powerline web site quotes Seymour Head teacher, Jenny

Dunn; "The high speed connection really lets us take advantage of the

educational potential of the Internet. With a normal connection the children

could lose interest waiting for pages to download. The new system means

information arrives virtually instantaneously, thereby maximizing teaching

time and keeping children on task. This set is amazingly flexible in

educational terms, and not only gives us the additional medium with which

to improve standards, but prepares us for the National Grid for Learning."

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1.3.2 Powerline Trials: Stanley Road

Following the success at Seymour Park, a more

comprehensive trial was initiated at the Stanley Road electricity substation,

also located in

Manchester. The crux

of this trial was to test

the limits of

Powerline technology

and make sure that it

could meet industry

standards even in worst case scenarios.

The Stanley Road substation was set up to use two distributors

to serve two distinct neighborhoods. Northumberland Close is located 350

meters from the substation and Seymour Close is located 600 meters from

the substation. Fifteen users were chosen between the two neighborhoods

to participate in the pilot program. They received various data and

telephone services as well as remote metering/information services.

Unfortunately, the results of the trial are unobtainable. Nortel

and Nor.Web claim that the results of this trial and similar trials in the

United States are being protected for competitive reasons. The only

indication of the trial’s success is a subjective quote from Nor.Web. The

quote states that "results produced over this period have now proved

conclusively that Nor.Web’s technology provides a commercially viable

alternative to established means of telecommunications delivery to

customer premises."

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1.4.0 Application areas offered by Powerline communications

PLC offers end-users a broad spectrum of applications and

services including broadband Internet access, voice over IP, multimedia

services, telecommunication, home automation and energy

managemen(near energy services). Powerline offers the opportunity for

the PC to be integrated into the household as never before. As part of the

household power grid, PCs could easily be programmed to turn off lights

and control security devices.

1.4.1 Powerline telecommunication

Powerline telecommunications is a rapidly evolving market

that utilises electricity power lines for the high speed transmission of data

and voice services. The especially exciting thing about the potential for

PLT is that it holds the promise of solving the underlying structural

problem confronting the local access market today. PLT can provide the

holy-grail of a much needed, highly elusive, alternative source of

ubiquitous local loops other than the incumbent telco operator, something

we sadly have yet to see happen on a sufficient scale and scope. Indeed,

what make PLT so attractive from a public policy point of view are the

facts that:

The power grid is ubiquitous; it constitutes an existing network

infrastructure to billions of private consumers and businesses

The power grid offers last-mile conductivity

The power grid supports information based services with strong

growth potential.

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Seminar Report Powerline Communication1.4.2 Home Automation

The Home Plug Powerline Alliance (HPA), a U.S. consortium

of 90 members, including such high-tech giants as Cisco, Intel, Motorola,

and Hewlett-Packard is working on technology to link appliances such as

TVs, computers and cookers via the home electrical system.

Appliance makers like Samsung Electronics Co. have been

solidifying cooperation with their technology partners to enable them to

market Internet-controllable home appliances this year. Samsung plans to

set up a “Dream LG” site on its homepage to advertise its Internet-enabled

products to potential customers.

1.4.3 Internet access

Power line communications can also be used to interconnect

home computers, peripherals or other networked consumer peripherals.

Specifications for power line home networking have been developed by a

number of different companies within the framework of the HomePlug

Powerline Alliance, the Universal Powerline Association and the HD-PLC

Alliance.

The Intellon, its PowerPacketTM Powerline networking

chipset, the first product certified as compliant with the HPA’s 1.0

Specification . The chipset allows users to access the Internet and connect

computers and other devices at speeds up to 14 mbps by simply plugging

into power outlets throughout a home or small office.

1.4.4 Power management (near energy services)

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Near energy services are defined as energy services with in the

confines of current business which ads new forms, features and scales.

Examples are remote billing, remote metering, demand side e management

distribution automation and remote control of supply. Advantages of such

system for utilities lie in their potential for cost cutting and improving

customer loyalty

1.5.0 Potential Advantages of Digital Powerline Technology

This telecommunications model has multiple advantages over

others including speed, an established local loop, and dedicated

connections. These advantages make Digital Powerline technology an

attractive alternative for telecommunications systems.

In the Digital Powerline model, small LANs are created; they

terminate at each local electricity substation. These LANs will share a

T1/E1 connection to the Internet, similar to a corporation leasing a T1 line.

Individual users should experience tremendous speed increases over

conventional 28.8kbs or 56kps dialup connections, even at peak usage.

Another inherent advantage to the Digital Powerline model is

the fact that it works well over the existing electric power infrastructure (at

least in the UK, see the Limitations section below). Only the substation

server equipment and customer conditioning/service units need to be

installed in order to establish a Digital Powerline network.

Dedicated, multipurpose communication lines make the

Digital Powerline model an attractive option for the information age. Wide

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Seminar Report Powerline Communicationbandwidth and frequency division multiplexing allow for multiple lines to a

single household. Ideally, an entire family could utilize their own

communication devices simultaneously, whether telephone or PC, without

interrupting one another.

Powerline carry signals for long distances without requiring

regeneration. Their near light speed propagation makes them very powerful

for fast delivery of video and audio data. There is no topology limitation

for power lines.

High transmission rate, right now 3 mbps in uploading and

downloading. The data transmission rate is expected up to 200 mbps in the

future by improving the PLC chip.

Permanent on-line connection with the potential for lower

charges. No need for complicated wiring and additional installations. Move

your computers and appliances where you want. Secure data-encryption.

Lower investment costs compared to those envisaged for other broadband

data access systems.

1.6.0 Potential Extensions to Digital Powerline Technology

There are many possible extensions to the Digital Powerline

model. Those mentioned in reviews and technical journals include "the

wired home" and remote customer information services. Since Digital

Powerline creates a LAN type environment by running IP, people could

theoretically control all of the appliances in their home from their PC or a

remote device. Each home on the neighborhood LAN would operate as a

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Seminar Report Powerline Communicationsub-network of the LAN and each electrical outlet could be treated as a

node on that sub-network.

The Nortel web site predicts, "It could also be feasible to have

an Internet address for every plug in the house, through which you could e-

mail, for example: ‘fridge@home’ and study the picture relayed by the

video camera to see what shopping you require; or you could remotely turn

the lights off and the burglar alarm on using your own password."

Remote services such as remote metering have already been

tested under this model and many more services are possible. Because the

service provider can keep track of electricity and bandwidth usage via the

network, customers will also be able to monitor their usage, reliably predict

billing and keep an eye on household usage (i.e. the teenager’s phone

usage).

1.7.0 Current Limitations of Digital Powerline Technology

1.7.1 Electro-Magnetic Radiation Issues

Powerline solutions, like phone line solutions, are

unintentional radiators. Emissions can potentially cause interference with

radio, television, community antenna television, telephone and DSL

services.

Second generation PLC technologies are using techniques like

OFDM, which substantially reduce the potential of interference to radio

users, thanks to a decrease in transmitted power spectral density. The

OFDM modulation spreads the signal over a very wide bandwidth, thus

reducing the amount on power injected at a single frequency. Field trials of

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Seminar Report Powerline CommunicationPLC technologies carried out during the last 2 years in Europe (Spain,

Italy, Germany), North America, South America (Chile, Brazil) and Asia

(Singapore) have shown that interference with radio users is no longer a

problem for PLC. The same technique explains why current PLC

technology does not affect other appliances in the home.

1.7.2 Addressing issue

As the number of users and devices connected to Power Lines

increases by orders of magnitude, it becomes clear that we cannot satisfy

the demand using IPv4/NAT, at least not without enormous administrative

complexity. A much larger address space is needed to provide end-to-end

connectivity in a simple manner and to allow new applications and services

to work in a transparent manner.

Clearly, the solution of problem is with IPv6, or Next

Generation Internet Addresses (IPNG) unlimited address space of IPv6 is

needed to provide end-to-end connectivity and allow new applications and

services to work in a transparent manner across PLC networks at massive

scale (imagine every power socket in Beijing or Mumbai becoming an

Internet access point!).

1.7.3 Security

The transmission of data over a network that anybody has

access to could also pose a data security problem, however. Tapping the

signal could allow somebody to eavesdrop on communications. Only data

encryption eliminates that problem.

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Seminar Report Powerline Communication1.7.4 Noise interference

Power line networking is also vulnerable to interference from

devices connected to the power infrastructure, such as microwaves and

computers.

This can be solved by either using repeaters or dynamic

change of frequencies.

1.7.5 Regulatory and standardization issues

Powerline's maximum access speed is shared with all users

connected to the same local network station. The more people that are

simultaneously on the Internet, the lower the speed obtained.

Several implementation issues have held back Digital

Powerline in North America and the UK. Respectively, the problems are

the numbers of users per transformer and the size and shape of light poles.

In North America, a transformer serves from 5 to 10

households while in Europe a transformer serves 150 households. Digital

Powerline signals cannot pass through a transformer. Therefore, all

electrical substation equipment needed for Digital Powerline has to be

located after the transformer. Since there are fewer households per

transformer in North America, predicted equipment costs are prohibitive.

However, this conclusion has been debated. Analysts suggest that 100%

subscription rates are possible in the US, and that at such rates Digital

Powerline is profitable. Conventional wisdom suggests that there is a way

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Seminar Report Powerline Communicationto make Digital Powerline profitable in North America, whether it is

through bundling a variety of services or higher fees.

Soon after the first trials of Digital Powerline in the UK, some

unanticipated problems arose. Certain radio frequencies were suddenly

deluged with traffic, making it impossible to transmit on those frequencies.

BBC, amateur radio, and the UK’s emergency broadcasting service were

affected. The apparent culprits were standard light poles. Then it became

clear that by pure chance British light poles were the perfect size and shape

to broadcast Digital Powerline signals. This situation posed problems not

just because of the frequencies involved but also because anyone could

listen in on the traffic. Nor.Web is addressing the problem by proposing to

lease the frequencies involved from their owners and offering amateur

radio operators a new frequency. Negotiations on this topic are currently

taking place in London. The privacy issue has not been fully addressed at

this point, besides suggestions that all sensitive information should be

encrypted.

While the promise of Powerline Telecommunications is great,

it is important for everyone to understand that this technology is in its

infancy and there are several hurdles the Powerline industry is working

hard to overcome to make PLT a true close substitute to the existing

incumbent public switched telephone network (PSTN) in the United States.

Specifically, the main weaknesses of PLT products and services are that:

(a) They are still at the developmental stage;

(b) There is no significant installed customer base to date;

(c) And the distances that Powerline technology can cover are limited.

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Moreover, the industry is working hard to resolve the complex

issues of standardization and interoperability.

1.8.0 The Market for Digital Powerline

Trends in both the electric and telecommunications industry

have lead to a climate where Digital Powerline should be a big player.

These trends include customer demand for affordable and high speed

Internet access, deregulation of electrical utilities, and the repercussions of

a variety of telecommunications legislation.

Customers want cheaper, faster, and more reliable access to

the Internet right now. Not only can Digital Powerline provide that type of

service, but it will be available before other broadband access technologies.

Therefore Digital Powerline has both a time to market and cost advantage.

The utility industry is facing deregulation in North America,

Europe, and some parts of Asia. Deregulation means increased competition

in the slow growing electricity market with little protection for utilities. An

unenviable position indeed. Consequently, many utilities are actively

seeking to diversify into other, more profitable, industries. For many

utilities telecommunications and Internet services have been a sensible

choice. That option can only become more popular as Digital Powerline

matures.

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Digital Powerline offers a deregulated utility several options

and advantages. The utility can either lease the rights to implement Digital

Powerline on its electrical grid or develop the technology itself. The

advantages include the low cost of the local loop, differentiating the utility

from other utilities, and bundling a variety of services.

The most recent telecommunications act has tried to make it

easier for all types of telecommunications firms to sell local services and

long distance services. However, Regional Bells actually have control over

local lines and charge other companies who place calls on their lines. Many

of the larger phone companies have sought to get around these charges by

building or leasing their own networks to connect to local points. Digital

Powerline is an existing network that fits those needs. Expect to see smaller

telecommunications companies partnering with electrical utilities to

provide alternative local phone service.

1.8.1 Who is testing or has tested the technology :

PLC abroad

Proof that the PLC concept works in practice was furnished by

a series of field trials by Main.net of Israel, Ascom of Switzerland and

some other companies in 16 European countries from Portugal to

Scandinavia, as well as in Hong Kong, Korea, India, Singapore and the

Americas. These trials fulfilled all expectations of reliability, functionality

and the practical applications of Powerline communications. The first

installations are now already up and running or about to go live.

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Users in Germany include the electricity companies RWE

Energie Essen and EnBW Energie Baden-Württemberg, while in Spain the

energy and telecoms group Endesa uses PLC technology. Lina.Net of

Iceland, a subsidiary of Reykjavik Energy, has recently begun introducing

PLC technology with the declared objective of providing private

households with fast Internet access over the power grid rather than the

telephone network. In Sweden Sydkraft, one of the leading energy

providers in Scandinavia uses PLC for bridging the last mile as well as for

networking inside buildings.

PLC in USA

Broadband over power lines (BPL), also known as power-line

Internet or powerband, is the use of PLC technology to provide broadband

Internet access through ordinary power lines. A computer (or any other

device) would need only to plug a BPL "modem" into any outlet in an

equipped building to have high-speed Internet access. International

Broadband Electric Communications or IBEC and other companies

currently offer BPL service to several electric cooperatives.

BPL may offer benefits over regular cable or DSL

connections: the extensive infrastructure already available appears to allow

people in remote locations to access the Internet with relatively little

equipment investment by the utility. Also, such ubiquitous availability

would make it much easier for other electronics, such as televisions or

sound systems, to hook up. Cost of running wires such as ethernet in many

buildings can be prohibitive; Relying on wireless has a number of

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Seminar Report Powerline Communicationpredictable problems including security, limited maximum throughput and

inability to power devices efficiently.

But variations in the physical characteristics of the electricity

network and the current lack of IEEE standards mean that provisioning of

the service is far from being a standard, repeatable process. And, the

amount of bandwidth a BPL system can provide compared to cable and

wireless is in question. The prospect of BPL could motivate DSL and cable

operators to more quickly serve rural communities. [1]

PLC modems transmit in medium and high frequency (1.6 to

80 MHz electric carrier). The asymmetric speed in the modem is generally

from 256 kbit/s to 2.7 Mbit/s. In the repeater situated in the meter room the

speed is up to 45 Mbit/s and can be connected to 256 PLC modems. In the

medium voltage stations, the speed from the head ends to the Internet is up

to 135 Mbit/s. To connect to the Internet, utilities can use optical fiber

backbone or wireless link.

Deployment of BPL has illustrated a number of fundamental

challenges, the primary one being that power lines are inherently a very

noisy environment. Every time a device turns on or off, it introduces a pop

or click into the line. Energy-saving devices often introduce noisy

harmonics into the line. The system must be designed to deal with these

natural signaling disruptions and work around them. For these reasons BPL

can be thought of as a halfway between wireless transmission (where

likewise there is little control of the medium through which signals

propagate) and wired transmission (but not requiring any new cables).

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Broadband over power lines has developed faster in Europe

than in the United States due to a historical difference in power system

design philosophies. Power distribution uses step-down transformers to

reduce the voltage for use by customers. But BPL signals cannot readily

pass through transformers, as their high inductance makes them act as low-

pass filters, blocking high-frequency signals. So, repeaters must be attached

to the transformers. In the U.S., it is common for a small transformer hung

from a utility pole to service a single house or a small number of houses. In

Europe, it is more common for a somewhat larger transformer to service 10

or 100 houses. For delivering power to customers, this difference in design

makes little difference for power distribution. But for delivering BPL over

the power grid in a typical U.S. city requires an order of magnitude more

repeaters than in a comparable European city. On the other hand, since

bandwidth to the transformer is limited, this can increase the speed at

which each household can connect, due to fewer people sharing the same

line. One possible solution is to use BPL as the backhaul for wireless

communications, for instance by hanging Wi-Fi access points or cellphone

base stations on utility poles, thus allowing end-users within a certain range

to connect with equipment they already have.

The second major issue is signal strength and operating

frequency. The system is expected to use frequencies of 10 to 30 MHz,

which has been used for many decades by amateur radio operators, as well

as international shortwave broadcasters and a variety of communications

systems (military, aeronautical, etc.). Power lines are unshielded and will

act as antennas for the signals they carry, and have the potential to interfere

with shortwave radio communications. Modern BPL systems use OFDM

modulation, which allows them to mitigate interference with radio services

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Seminar Report Powerline Communicationby removing specific frequencies used. A 2001 joint study by the American

Radio Relay League (ARRL) and HomePlug Powerline Alliance showed

that for modems using this technique "in general that with moderate

separation of the antenna from the structure containing the HomePlug

signal that interference was barely perceptible at the notched frequencies"

and interference only happened when the "antenna was physically close to

the power lines" (however other frequencies still suffer from interference).

1.9.0 Transmitting Radio programs

Sometimes PLC was used for transmitting radio programs

over powerlines. When operated in the AM radio band, it is known as a

carrier current system. Such devices were in use in Germany, where it was

called Drahtfunk, and in Switzerland, where it was called

Telefonrundspruch, and used telephone lines. In the Soviet Union, PLC

was very common for broadcasting since the 1930s because of its low cost

and accessibility. In Norway the radiation of PLC systems from powerlines

was sometimes used for radio supply. These facilities were called

Linjesender. In all cases the radio programme was fed by special

transformers into the lines. To prevent uncontrolled propagation, filters for

the carrier frequencies of the PLC systems were installed in substations and

at line branches.

An example of the programs carried by "wire broadcasting" in Switzerland:

175 kHz Swiss Radio International

208 kHz RSR1 "la première" (French)

241 kHz "classical music"

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274 kHz RSI1 "rete UNO" (Italian)

307 kHz DRS 1 (German)

340 kHz "easy music"

1.10.0 Conclusion

Digital Powerline technology is an exciting alternative to

connecting to the Internet via phone and modem. Though this technology is

not commercially available yet in India and many countries, it should be

available before other broadband technologies due to the relatively low

cost of its local loop. Though wireless connections are a favourate choice,

However, PLC’s high speeds will provide Internet access, video on

demand, local phone, and long distance phone services to customers at

cheaper cost.

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1.11.0 Reference

http://www.powerlineworld.com/powerlineintro.html

http://www.powerlinecommunications.net/

www.powerline-plc.com

www.powerline.com

www.wikipedia.org

O'Neal Jr., J.B. (1986) "The residential power circuit as a

communication medium," IEEE

Trans. on Consumer Electronics, vol.

CE-32, No. 3, pp. 567-577. 

Malek, J.A. & Engstorm, J.R. (1976)

"R.F. impedance of United States

and European power lines," IEEE

Trans. on Elec. Comp., vol. EMC-

18, pp. 36-38. 

CONTENTS

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1.0.0 Introduction 1

1.1.0 History 2

1.2.0 Overview of Technology 2

1.2.1 The Server 3

1.2.2 The HFCPN Conditioning Unit 4

1.2.3 Service Unit 5

1.3.0 CASE STUDY 6

1.3.1 Powerline Trials: Seymour Park Primary School 6

1.3.2 Powerline Trials: Stanley Road 7

1.4.0 Application areas offered by Powerline communications 8

1.4.1 Powerline telecommunication 8

1.4.2 Home Automation 9

1.4.3 Internet access 9

1.4.4 Power management (Near energy services) 9

1.5.0 Potential Advantages of Digital Powerline Technology 10

1.6.0 Potential Extensions to Digital Powerline Technology 11

1.7.0 Current Limitations of Digital Powerline Technology 12

1.7.1Electro-Magnetic Radiation Issues 12

1.7.2 Addressing issue 13

1.7.3 Security 13

1.7.4 Noise interference 13

1.7.5 Regulatory and standardization issues 14

1.8.0 The Market for Digital Powerline 15

1.8.1 Who is testing or has tested the technology? 17

PLC abroad 17

PLC in USA 18

1.9.0 Transmitting Radio programs

1.10.0 Conclusion 20

1.11.0 Reference 21

Dept. of EEE BMSCE, Bangalore24

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Seminar Report Powerline Communication

ABSTRACT

Power Line Communications (PLC) allows transmission of

data over power lines. PLC is potentially the network with the deepest

capillarity in the world, since power lines are almost ubiquitous. Powerline

communications is a rapidly evolving market that utilizes electricity power

lines for the high-speed transmission of data and voice services.

PLC works by transmitting high frequency data signals

through the same power cable network used for carrying electricity power

to household users. Such signal cannot pass through a transformer. This

requires devices ("outdoor devices") that combine the voice and data

signals with the low-voltage supply current in the local transformer stations

to bridge the last mile. In the house, "indoor devices" (adapters) are used in

order to filter out the voice and data signals and to feed them to the various

applications (e.g. PC/Internet, telephone, etc.).

The technology has roots going back to the 1940s. It has been

used by power utilities for simple telemetering and control of electrical

equipment in their networks. What is new is the integration of activities

outside the building with those inside the building at a much higher

bandwidth, 2.5 mbps or higher – this means voice and data transmission via

the mains supply voltage network right through to every power socket in

the building, as well as in the reverse direction at high speed.

Dept. of EEE BMSCE, Bangalore25

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Seminar Report Powerline Communication

ACKNOWLEDGEMENT

The materialization of ideas and views of this seminar has

seen valuable contribution from many friends and well-wishers. I take this

opportunity to thank them all. First of all, I thank Dr. Ravishankar Dixit,

Prof and Head, Department of Electrical and Electronics Engineering,

B.M.S. College of Engineering for giving me this opportunity to present

the seminar. I also thank my teachers who assisted me in this endeavor.

SANTOSH. R

Dept. of EEE BMSCE, Bangalore26