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BROADBAND OVER POWER LINE (BPL)
#1

A SEMINAR REPORT ON
BROADBAND OVER POWERLINE

Submitted by
NITHIN G

DEPARTMENT OF ELECTRONICS AND COMMUNICATION ENGINEERING
SREE CHITRA THIRUNAL COLLEGE OF ENGINEERING, THIRUVANANTHAPURAM

ABTSRACT
Despite the spread of broadband technology in the last few years, there are significant areas of the world that don't have access to high-speed Internet. When weighed against the relatively small number of customers Internet providers would gain, the incremental expenditures of laying cable and building the necessary infrastructure to provide DSL or cable in many areas, especially rural , is too great. But if broadband could be served through power lines, there would be no need to build a new infrastructure. Anywhere there is electricity there could be broadband. Technology to deliver high-speed data over the existing electric power delivery network is closer to reality in the marketplace. Broadband OverPowerline, is positioned to offer an alternative means of providing high-speed internet access, VoicE over Internet Protocol (VoIP), and other broadband services, using medium and low voltage lines to reach customers homes and businesses. By combining the technological principles of radio, wireless networking, and modems, developers have created a way to send data over power lines and into homes at speeds between 500 kilobits and 3 megabits per second (equivalent to DSL and cable). By modifying the current power grids with specialized equipment, the BPL developers could partner with power companies and Internet service providers to bring broadband to everyone with access to electricity


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1. INTRODUCTION

1.1.WHAT IS BPL
Broadband over Power Line (BPL) is a technology that allows voice and Internet data to be transmitted over utility power lines. BPL is also sometimes called Power-line Communications or PLC. Many people use the terms PLC and BPL interchangeably. We chose to use the term broadband over power line for consumer applications. In order to make use of BPL, subscribers use neither a phone, cable nor a satellite connection. Instead, a subscriber installs a modem that plugs into an ordinary wall outlet and pays a subscription fee similar to those paid for other types of Internet service .Here wediscusses two types of BPL: 1) Access BPL, and 2) In-house BPL. Access BPL is a technology that provides broadband access over medium voltage power lines.voltage power lines are the electric lines that you see at the top of electric utility poles beside the roadways in areas that do not have underground electric service. Typically there are three electric lines (called phases A, B and C), each carrying several thousand volts. One phase is usually enough to power the houses on a residential street, two or even three phases can be joined together to power the big electric motors in an industrial or commercial area. In-house BPL is a home networking technology that uses the transmission standards developed by the Home Plug Alliance.


1.2 MAIN COMPONENTS OF BPL SYSYTEM

The Last Mile is the portion of the network that connects end users, such as homes and business, to high-speed services and the Internet. For residential broadband service customers who get cable modem service, for example, the drop wire connecting the interface on a house to cable
company s network and the wire from the interface connecting to the wall plates in the home would all be part of the last mile.

BPL modems use silicon chips designed to send signals over electric power lines, much like cable and DSL modems use silicon chips designed to send signals over cable and telephone lines. Advances in processing power have enabled new BPL modem chips to overcome difficulties in sending communications signals over the electric power lines.

Inductive couplers are used to connect BPL modems to the medium voltage power lines. An inductive coupler transfers the communications signal onto the power line by wrapping around the line, without directly connecting to the line. A major challenge is how to deliver the signal from the medium voltage line to the low voltage line that enters your house, because the transformer that lowers the electric power from several thousands volts down to 220/110 is a potential barrier to the broadband signal.

Router is a device that acts as an interface between two networks and provides network management functions.
Repeater is a physical-layer hardware device used on a network to extend the length, topology or interconnectivity of the physical medium beyond that imposed by a single segment.

Concentrator/Injector is a device that aggregates the end-user CPE data onto the MV (medium voltage) grid. Injectors are tied to the Internet backbone via fiber of T1 lines and interface to the MV power lines feeding the BPL service area.

Carrier-Current System: There are a number of types of BPL systems, using different approaches and architecture. All are Carrier-Current systems, a term used to describe systems that intentionally conduct signals over electrical wiring or power lines.

1.3AN OVERVIEW OF HOW BPL WORKS

At a high-level, a Powerline Telecom network consists of three key segments, the backbone, themiddle mile, and the last mile as shown . The BPL vendors are primarilyseeking to address the last mile segment all the way into the home market.From the end user s perspective, BPL technology works by sending high-speed data alongmedium or low voltage power lines into the customer s home. The signal traverses the networkover medium and low voltage lines either through the transformers or by-passes the transformerusing bridges or couplers. The technology transports data, voice and video at broadband speeds tothe end-user s connection. The user only needs to plug an electrical cord from the BPL modem into any electrical outlet then plug an Ethernet or USB cable into the Ethernet card or USBinterface on their PC. Any Internet Service Provider (ISP) can interface with the BPL networkand provide high speed Internet access. The data signal can also interconnect with wireless, fiberor other media for backhaul and last mile completion. The actual hardware used for thedeployment varies by manufacturer but typically feature some common characteristics.


Fig1.an overview of bpl system
By combining the technological principles of radio, wireless networking, and modems,developers have created a way to send data over power lines and into homes at speeds equivalent to those of DSL and cable. By modifying the current power grids with specialized equipment, the BPL developers could partner with power companies and Internet service providers (ISPs) to bring broadband to everyone with access to electricity.The Internet is a huge network of networks that are connected through cables, computers, and wired and wireless devices worldwide. Typically, large ISPs lease fiber-optic lines from the phone company to carry the data around the Internet and eventually to another medium (phone, DSL or cable line) and into the homes. Trillions of bytes of data a day are transferred on fiber optic lines because they are a stable way to transmit data without interfering with other types of transmissions. The idea of using AC (alternating current) power to transfer data is not new. By bundling radiofrequency (RF) energy on the same line with an electric current, data can be transmitted without the need for a separate data line. Because the electric current and RF vibrate at different frequencies, the two don t interfere with each other. Electric companies have used this technology for years to monitor the performance of power grids. There are even networking solutions available today that transfer data using the electrical wiring in a home or business. But this data is fairly simple and the transmission speed is relatively slow. There are several different approaches to overcoming the hurdles presented when transmitting data through power lines. The power lines are just one component of electric companies' power grids. In addition to lines, power grids use generators, substations, transformers and other distributors that carry electricity from the power plant all the way to a plug in the wall. When power leaves the power plant, it hits a transmission substation and is then distributed to high voltage transmission lines. When transmitting broadband, these high-voltage lines represent thefirst hurdle. The power flowing down high-voltage lines is between 155,000 to 765,000 volts. That amount of power is unsuitable for data transmission. It's too "noisy." Both electricity and the RF used to transmit data vibrate at certain frequencies. In order for data to transmit cleanly from point to point, it must have a dedicated band of the radio spectrum at which to vibrate without interference from other sources. Hundreds of thousands of volts of electricity don't vibrate at a consistent frequency. That amount of power jumps all over the spectrum. As it spikes and hums along, it creates all kinds of interference. If it spikes at a frequency that is the same as the RF used to transmit data, then it will cancel out that signal and the data transmission will be dropped or damaged en rout.

An overview of power line system


Fig 1.1 power line system
BPL bypasses this problem by avoiding high-voltage power lines all together. The system drops the data off of traditional fiber-optic lines downstream, onto the much more manageable 7,200 volts of medium-voltage power lines. Once dropped onto the medium-voltage lines, the data can only travel so far before it degrades .To counter this, special devices are installed on the lines to act as repeaters. The repeaters take in the data and repeat it in a new transmission, amplifying it for the next leg of the journey. In one model of BPL, two other devices ride power poles to distribute Internet traffic. The Coupler allows the data on the line to bypass transformers, and the Bridge , a device that facilitates carrying the signal into the homes. The transformer's job is to reduce the 7,200 volts down to the 240-volt standard that makes up normal household electrical service. There is no way for low-power data signals to pass through atransformer, so you need a coupler to provide a data path around the transformer. With thecoupler, data can move easily from the 7,200-volt line to the 240-volt line and into the housewithout any degradation.
The last mile is the final step that carries Internet into the subscriber's home or office. In the various approaches to last-mile solutions for BPL, some companies carry the signal in with the electricity on the power line, while others put wireless links on the poles and send the data wirelessly into homes. The Bridge facilitates both. The signal is received by a powerline modem that plugs into the wall. The modem sends the signal to your computer. BPL modems use silicon chipsets specially designed to handle the work load of pulling data out of an electric current. Using specially developed modulation techniques and adaptive algorithms, BPL modems are capable of handling power line noise on a wide spectrum.
A BPL modem is plug and play and is roughly the size of a common power adapter. It plugs into a common wall socket, and an Ethernet cable running to your computer finishes the connection. Wireless versions are also available.

Fig 1.2 a bpl modem

2.INDUSTRY STRUCTURE


Electric utilities may not necessarily want to enter the communications business. In fact ,they may want to leave that part of BPL to a partner, perhaps an ISP, a Competitive Local ExchangeCarrier (CLEC), or a long distance company looking for an alternative last mile path to their customers. Current focus of most electric utilities is using BPL for an intelligent electric distribution grid. Power companies have often employed low-speed power line communication for their own internal use to monitor and control equipment in the power grid. This could result in lower electric power costs, less pollution and greater reliability and security, essentially, more intelligent electric power grid.
The Broadband services enabling partners may be in one or more of the delivery segment or role.
:The last mile: This is the portion of the network that connects end users, such as homes and business, to high-speed services and the Internet. For residential broadband service customers who get cable modem service, for example, the drop wire connecting the interface on a house tocable company s network and the wire from the interface connecting to the wall plates in thehome would all be part of the last mile.
The middle mile : This portion of the network consists of high-speed fiber backbones and other middle-mile pipes that connect computers to networks, connect those networks into thecomplex that constitutes the Internet, and deliver traffic among ISPs, content providers, onlineservice companies, and other customers.
Internet service providers (ISPs): These are companies that receive and translate internetbounddata and help customers obtain online information from the Internet.
Content providers : This part of broadband consists of companies that provide information,goods, and services available to consumers through the Internet.These characteristics and distinctions are based on network functionality and the fact that each ofthese categories has its own economic properties with distinct regulatory issues. Currently there isa dearth of competition in the provision of middle -mile services, which means existing providerscan discriminate against their customers. Content providers, on the other hand, raise competitiveissues in terms of their ability or willingness to engage in exclusive contracts for the carrying oftheir content, as well as posing challenges in the area of consumer protection and free speech

The following Figure shows key players interested in BPL, affording utilities theopportunity to structure partnerships to push the technology forward


Fig.2 key players in bpl


3.ADVANTAGES FOR BPL AS AN ACESS TECHNOLOGY


Most stakeholders in BPL industry suggest that BPL could offer a number of significant benefits in the delivery of broadband services to homes and businesses. A number of BPL proponents submit that this technology could increase the availability of broadband and improve the competitiveness of the broadband services market. Many players believe that Access BPL could facilitate the ubiquitous availability of broadband services and bring valuable new services to consumers, stimulate economic activity, improve national productivity, and advance economic opportunity for the American public. The ubiquitous nature of BPL is expected to create theopportunity for providing new and innovative services to virtually any location serviced with electric outlets. The National Telecommunications and Information Administration (NTIA) states that BPL holds great promise as a new source of innovation and competition in the broadbandmarketplace. It believes that BPL has the potential to open new avenues of Internet access, to enable new and expanded services for utility companies, and to create a new platform for furtheradvances in communications technology.

3.1HOMELAND SECURITY AND NETWORK BENEFITS
The benefit is the ability of BPL technology to improve the provision of electric power service and therefore advance homeland security. The BPL technology could also be used toassist the utility companies by adding intelligent capabilities to the electric grid, thereby improving efficiency in activities such as energy management, power outage notification and automated meter reading. As per United Power Line Council (UPLC), Access BPL would allow electric utilities to better monitor and control electric system operations and thereby improve thereliability of their service and reduce costs to consumers. Under the Mission Essential VoluntaryAssets (MEVA) guidelines, utilities are responsible for ensuring secure infrastructure power forfederal facilities, including military bases, and state, city and local government. BPL will alsoenhance security and enable other security applications such as video surveillance consistent with the MEVA guidelines.

3.2 CONSUMER BENEFITS
The supporters of BPL expect it to improve the competitiveness of the market for broadband services. It offers the long sought third wire (other two being telephone and cable) for last-mile delivery of broadband communication services to residences and small businesses. The United
Power Line Council (UPLC) believes that BPL offers a unique opportunity in the broadband marketplace and that there is widespread interest in BPL among utilities. In the areas already served by other broadband providers, BPL will increase competition, which in turn will bring better service and lower prices for consumers.

3.2.1 GEOGRAPHICAL COVERAGE AND AVAILABILITY
It is forecasted that the ubiquitous nature of electric power grid will make it possible for Access BPL systems to bring broadband services to rural and other underserved locations. The American Public Power Association (APPA), for example, states that seventy five percent of its members serve communities with populations less than 10,000, many of which do not have access to broadband. 10 Current Technologies states that technical and economic considerations limit the deployment of cable and DSL. It submits that Access BPL is not constrained by these considerations and can deliver broadband to many of those unserved by other broadband technologies and bring the advantages of the Internet to the people who need them most. Itis also expected that the availability of Access BPL will make it possible for those persons whocurrently do not have access to broadband to better participate and compete in the informationage. The Office of the People s Counsel, District of Columbia (OPC DC) supports the efforts tofacilitate deployment of BPL because it has the potential to improve the District of Columbia stelecommunications landscape for consumers by providing a solution to the digital divide thatcurrently exists in the District of Columbia and to increase the number of broadband service
providers in the District.

3.2.2 A BETTER CONNECTED APPLIANCE

An interesting aspect of BPL is that every electric device is connected to the electric distribution network. Potentially, BPL could let chips in every electric device talk to each other. Of course, a Wi-Fi, Blue Tooth or other wireless chip could be placed in every appliance. But BPL may be a better solution. Those who had PC s before the Internet exploded remember the difference in functionality between a standalone PC and a networked PC. Networking every electric device together over the power lines might result in a similar growth in productivity and convenience for the home and office.


4. APPLICATIONS

Advances in BPL communications over medium technology now allow for high-speed, broadband and low voltage lines yielding potential market opportunities. Using BPL technology theutilities can now offer new facilities-based competition for broadband services and provide high speedaccess to qualified urban, suburban, and rural areas of the country.
BPL can help utilities maximize the value of their existing assets by leveraging the transmission and distribution network infrastructures. The business development managers in utilities, atpresent, are focused on more traditional transition into the market via energy related applicationssuch as Automatic Meter Reading (AMR), demand side management, outage notification,distribution transformer overload analysis, phase loss monitoring, fault characterization, andseveral others.There are a number of applications BPL architecture can help deliver. These applications are shown below


Table no.1 Applications

5 FEASIBILTY ASSESMENT


Several utilities, particularly municipally owned ones, have been running pilots of broadbandservices over fiber to the home (FTTH), and some have moved to full deployment. While BPLhas come a long way in the past two years, some issues, especially the lack of standards for Access BPL , remain unresolved. However, the technologies appear to work well enough toprovide commercial service. In fact, the state of BPL today strikes in many ways resemblances towhat cable modem service was like in 1997. There are several proprietary technologies that work,standards are not yet there, and a pretty significant culture change will have to occur in utilitypersonnel, just as it did for cable.Willingness of utilities to invest in new technologies and take risks, is to some extent, determinedby what constituencies they serve. Historically, it appears that Munis have been quicker toembrace new technology, since they do not have to produce results for shareholders.

5.1 TECHNICAL
Access BPL equipment consists of injectors (also known as concentrators), repeaters, andextractors. BPL injectors are tied to the Internet backbone via fiber of T1 lines and interface to the Medium Voltage (MV) power lines feeding the BPL service area. MV lines, typically carrying 1,000 to 40,000 volts, bring power from an electrical substation to a residential neighbourhood. Low Voltage distribution transformers step down the line voltage to 220/110 volts for residential use. MV power lines may be overhead on utility poles that are typically 10 meters above the ground. Three-phase wiring generally comprises an MV distribution circuit running from a substation, and these wires may be physically oriented on the utility pole in a number of configurations (e.g. horizontal, vertical, or triangular). This physical orientation may change from one pole to the next. One or more phase lines may branch out from the three phase lines to serve a number of customers. A grounded neutral conductor is generally located below the phase conductors and runs between distribution transformers that provide Low Voltage (LV) electric power for customer use. In theory, BPL signals may be injected onto MV power lines between two-phase conductors, between a phase conductor and the neutral conductor, or onto a single phase or neutral conductor .Extractors provide the interface between the MV power lines carrying BPL signals and the households within the service area. BPL extractors are usually located at each LV distribution transformer feeding a group of homes. Some extractors boost BPL signal strength sufficiently allow transmission through LV transformers and others relay the BPL signal around thetransformers via couplers on the proximate MV and LV power lines. Other kinds of extractorsinterface with non-BPL devices (e.g. WiFi, WiMax) that extend the BPL network to the customers premises. For long runs of MV power lines, signal attenuation or distortion through the power line may lead BPL service providers to employ repeaters to maintain the required BPL signal strength and fidelity. Figure illustrates the basic BPL system, which can be deployed in cell-like fashion over a large area served by existing MV power lines.


fig 5.1bpl system in a large area

6 REGULATORY ISSUES AND CHALLENGES
The FCC has implemented new rules after obtaining comments from proponents of the new BPLservice, i.e., electric utilities and BPL vendors, as well as those who might be impacted by theBPL signals. On most electric utility poles below the four electric utility lines there is a lowersegment of the pole where telephone and cable television wires are attached (referred to as thecommunications space). One of the questions the FCC has addressed is whether radiated signalsfrom access BPL systems on the electric power lines would interfere with signals on the cable and telephone lines, and vice versa.Regulations in the BPL arena can broadly be grouped into three categories of issues as shown in the figure. Even though the Telecommunications Act of 1996 mandated that broadband service be widelyavailable in the United States, the actual market for that service today is a duopoly with customers in most jurisdictions connecting to the internet through either their incumbent local exchange carrier (ILEC), which provides broadband service through digital subscriber lines (DSL), or their local cable operator, which provides the service through cable modem. Duopoly does not necessarily provide consumers the opportunity to get the best combination of rates and services, and many now are looking to electric companies as a third competitive provider of broadband.
fig 5.2 regulatory issues

BPL technology provides the opportunity to have true competition for broadband service. Giventhe applications and services it can offer, it is incumbent upon regulators to adopt a uniform set ofrules and regulations that will facilitate the provision of BPL service in the United States whileensuring that public interest concerns are protected . In order to provide broadband access to allAmericans, the FCC and the states are defining and adopting a regulatory scheme that removesunnecessary barriers to market entry and permits electric companies to be competitive in themarketplace.


6.1 INTERFERENCE AND RADIOSTATIC

Powerline system is a type of carrier current system that electric utility companies have traditionally used for protective relaying and telemetry. They operate between 10 kilohertz (KHZ) and 490 KHZ, although today many utilities rely on the 1-30 megahertz (MHZ) bandwidth forBPL transmission. A carrier current system transmits radio frequency energy to a receiver by conduction over the electric power line.
Under Part 15 of the FCC s current rules, which regulate carrier current systems and powerline carrier systems, each is subject to different emission limits. The FCC also limits the amount ofconducted radio frequency (RF) energy that may be injected into a building s wiring by an RF device that receives power from the commercial power source, including carrier current systems that couple RF energy onto the AC wiring for communications purposes. This conducted energy can cause interference to radio communications by two possible paths.
First, the RF energy may be carried through electrical wiring to other devices also connected to the electrical wiring. Second, at frequencies below 30 MHZ, where wavelengths exceed 10 meters, long stretches of electrical wiring can act as an antenna, permitting the RF energy to be radiated over the airwaves. Due to low propagation loss at these frequencies, such radiated energy can cause interference to other services at considerable distances.

6.2 UNIVERSAL SERVICE AND POLE ATTACHMENTS
Currently, all interstate telecommunications, wireless phone, and paging service providers must contribute 6.8 percent of their long distance and international calling revenue to a universal service fund. The fund is designed to provide rural, low income, and other consumers access toadvanced and inter-exchange telecommunications services at reasonably comparable rates charged for similar services in urban areas. The obligation to contribute to the universal fund, if applied to BPL providers, would add to the costs of providing such service.Pole attachments have been an issue since before BPL technology arrived on the scene. Pursuant to the adoption of the Telecom Act, an electric utility had to provide access to its poles if the utility used its poles for any type of communications, including its own to any company requesting access. Under the FCC s rules, where access is mandated, the rates, terms, and conditions of access must be uniformly applied to all telecommunications carriers and cable operators that have or seek access. Utilities may deny access for reasons related to insufficient capacity, safety, reliability and other engineering purposes.

6.3CROSS-SUBSIDIES
Cross-subsidization is a particularly significant concern when a company provides one service in a competitive market, but is a monopoly provider of another service, as is the case with many electric companies. As for BPL technology, the concern is whether electric companies will use earnings or resources from the provision of electric service to subsidize their BPL businesses. Regulators will focus on this issue for two reasons first, such subsidies could provide electric companies with an unfair advantage in the broadband market and, second, needed resources that are diverted away from the provision of electric service could hurt quality of service.

7. FUTURE OF BPL
While in-home BPL is already on the scene with commercial products readily available, proliferation of Access BPL faces a more formidable challenge. RFI concerns are legitimate and specific cases have been documented. Standardization by the IEE for device compliance is critical to avoiding the proliferation of proprietary solutions. Companies manufacturing BPL devices will have to ensure their products meet the revised standards set forth by the FCC, which will increase the cost of the deployment. The electric companies are eager to pursue BPL, envisioning increased services and reduced operating costs as a result of the deployment (Forbes, 2005). Cable and DSL providers will be watching the emerging competition closely and, along with the ARRL, will be eager to ensure the BPL installations are meeting the requirements of the FCC.BPL companies such as Current Technologies Group will continue working with the electricity providers in more trials around the country while continuing to work through issues with RFI. At the same time, the ARRL will continue to monitor and report occurrences of RFI to defend licensed service

8.CONCLUSION
This paper presents BROADBAND OVER POWER LINE ,that is broadband connection through power line,ie the same power line which brings the electricity to our home.This can be a boon for the people in remote areas and especially to our country where ther are a lot f villages because electric line covers over 95% of the land. For that proper awareness must be done and people must be equipped with basic knowledge about computer.This technology is in its budding state and many countries have employed research teams to have a better understanding of this technology. This technology has greater advantages which makes it a blessing for developing countries like ours.
9 REFERENCES
1)Institute of Electrical and Electronics Engineers, Inc. (IEE) (July 2009). Retrieved December 2, 2009 from
http://standards.ieeannouncements/pr_p1675.html

2)IEE (July 2009). Retrieved December 2, 2009 from http://standards.ieeannouncements/pr_BPL.html

3)AARL Worldwide (2009). Retrieved December 2, 2009 from http://p1k.arrl ehare/bpl/WorldwideEx2.html

4)PLCA/UPLC (2009). Retrieved December 2, 2009 from http://uplc.utcfile_depot/0-10000000/0-
10000/7966/conman/Joint+Report+on+PLC.pdf

5)ARRL (2009), Retrieved December 2, 2009 from http://arrl
Box, Gary. Retrieved December 2, 2009 from http://arrltis/info/HTML/plc/files/BPL_paper.pdf

6)Federal Communications Commission, Rules Part 15 (2009). Retrieved December 2, 2009 from
http://fcc.gov/oet/info/rules/part15/part15-91905.pdf
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#2
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Power Line Communications

Presented By:
S.Siddarth IIrd Year CSE B.Santosh IIrd Year IT
Guru Nanak Engineering College

ABSTRACT

Broadband power line (BPL) is the term coined by the FCC for new modems (BPL modems) used to deliver IP-based broadband services on electric power lines. On April 23, 2003, the FCC adopted a Notice of Inquiry (NOI), expressing enthusiasm about the potential of the BPL technology to enable electric power lines to function as a third wire into the home, and create competition with the copper telephone line and cable television coaxial cable line. The FCC said that BPL service can be offered now using BPL modems that comply with existing FCC Rules. However, the FCC also asked whether changes to its rules are needed, either to remove unnecessary barriers to BPL service or to protect other devices from interference from BPL modems. BPL modems use silicon chips designed to send signals over electric power lines, much like cable and DSL modems use silicon chips designed to send signals over cable and telephone lines. Advances in processing power enable new BPL modem chips to overcome difficulties in sending communications signals over the electric power lines that could not be overcome with less computing power. BPL modem speed, like cable and DSL modem speeds, is changing rapidly with each advance in new technology, so it would be difficult to make any generalization here that would be accurate or timely. The FCC NOI discusses two types of BPL, In-house BPL and Access BPL.
Introduction

In-house BPL is a home networking technology that uses the transmission standards developed by the Home Plug Alliance. Products for in-home networking using the electric outlets in your home (or office) are available in stores now. In-house BPL products can comply relatively easily with the radiated emissions limits in Part 15 of the FCC's Rules, because the products connect directly with the low voltage electric lines inside your home or office. In-home networking, while exciting and innovative, is not a major policy concern for the FCC. What the FCC is really wrestling with is how to get broadband Internet access over "the last mile" to the home.
Access BPL is a new technology to carry broadband Internet traffic over medium voltage power lines. BPL modems that electric utilities and their service partners can install on the electric distribution network also are available now. Medium voltage power lines are the electric lines that you see at the top of electric utility poles beside the roadways in areas that do not have underground electric service. Typically there are three electric lines (called phases A, B and C), each carrying several thousand volts. One phase is usually enough to power the houses on a residential street, two or even three phases can be joined together to power the big electric motors in an industrial or commercial area. (You also may see a fourth wire that is the ground wire.)
Inductive couplers are used to connect BPL modems to the medium voltage power lines. An inductive coupler transfers the communications signal onto the power line by wrapping around the line, without directly connecting to the line. A major challenge is how to deliver the signal from the medium voltage line to the low voltage line that enters your house, because the transformer that lowers the electric power from several thousands volts down to 220/110 is a potential road block to the broadband signal. Several methods are now available that successfully solve this problem.
Interference issues between unlicensed devices, including BPL modems, and other electronic devices are governed by Part 15 of the FCC's Rules. All electronic devices sold in the U.S. have to meet FCC radio frequency (RF) emissions limits. When BPL modems are installed on underground electric lines, the communications signal is shielded by the conduit and the earth and as a result is unlikely to cause interference to other communications services. The FCC is more concerned about the interference potential of BPL signals transmitted on exposed, overhead medium voltage power lines.
Public comment responding to the NOI on BPL is invited by the FCC, both from the proponents of the new BPL service, i.e., electric utilities and BPL vendors, as well as those who might be impacted by the BPL signals. For example, on most electric utility poles you will notice that below the four electric utility lines there is a lower segment of the pole where telephone and cable television wires are attached (referred to as the communications space). One of the questions the FCC asks is whether radiated signals from access BPL systems on the electric power lines would interfere with signals on the cable and telephone lines, and vice versa. We can expect a lively debate in the comments filed in response to the NOI on this issue, since the parties involved are competing for the same customers.
A more intelligent electric power grid. Speaking of competitors, why should we care about any of this when 3G wireless cellular telephone networks, wireless in-home networking and Wi-Fi hotspots claim to have the answer to delivering broadband to everyone? Electric utilities are not just looking at BPL as a way of entering the communications business. In fact, they may want to leave that part of BPL to a partner, perhaps an ISP, a CLEC or a long distance company looking for an alternative last mile path to their customers. Electric utilities are interested in BPL because it can give them an intelligent electric distribution grid. This could result in lower electric power costs, less pollution and greater reliability and security.
A better connected appliance. What's interesting about BPL is that every electric device is connected to the electric distribution network. Potentially then, BPL could let chips in every electric device talk to each other. Could we put a Wi-Fi, Blue Tooth or other wireless chip in every appliance? Yes - but BPL may be a better solution. Those who had PC's before the Internet exploded remember the difference in functionality between a standalone PC and a networked PC. Networking every electric device together over the power lines might result in a similar growth in productivity and convenience for your home and office.
Power line communications (PLC), the transmission of high-speed data across the electric power network, has achieved several important milestones since we covered the United Power Line Council (UPLC) annual meeting last year (see WAVE issue 0237). Some of these milestones are positive, such as the first approval of PLC affiliate transaction rules by a state PUC (public utility commission), and some are potentially negative, such as the announcement of an FCC Office of Engineering and Technology (OET) proceeding to investigate PLC interference. On the whole the industry seems to be progressing quickly, with at least two vendors expecting to begin commercial roll-out within six months. But questions still swirl around the business case for wide-scale industry success.
This conference was notable as the first PLC event we have attended that did not kick off with a general tutorial. The organizers assumed that attendees understood the basic technology, and jumped right into updates from the vendors. Also notable was the inclusion of two operational support systems (OSS) vendors in the presentations. These companies provide suites of back-end services such as marketing, provisioning, customer service, and network management. Here was a clear indication that the industry is beginning to seriously consider the implications of rolling out an entirely new network and set of offerings. Because PLC uses existing wires, capital expenses are expected to be low, with operational costs driving expenditures. Controlling those operation costs with good OSS will be the key to a successful roll-out.
During the closing discussion session, Michael Noll, Director of Technology Research at CITI, asked for benchmarks--when should we check back with PLC, to see how it is doing? The panel members agreed on the following benchmarks for the industry:
18 months -- Widespread commercial deployment has begun, to significant numbers of people.
36 months -- PLC acquires its 1 millionth home.
Regulatory

Some of the most important recent PLC developments have been in the regulatory sphere. For the most part PLC has had a low public profile, and with little to no commercial activity yet most regulatory agencies are content to let it develop freely. But now, the FCC is beginning to look closely, as are some states.
At the federal level, the FCC has stated that PLC is a top priority for the OET in 2003, and they continue to be excited about the potential to provide facilities-based competition for the consumer broadband market. The biggest news from the FCC is the OET announcement that they will begin a proceeding this year to investigate any potential for interference by a PLC deployment. This caused enough of a stir that the two major PLC industry groups, the UPLC and Power Line Communications Association (PLCA), jointly filed a report with the FCC before the proceeding was formally announced. They ask the OET to proceed with as much speed as possible, since such an open regulatory issue will likely create uncertainty that could hamper industry growth. Utilities, risk-averse by nature, are unlikely to commit to a large deployment until regulations are stable.
At issue is unintentional radiation created by the PLC signal as it travels over power lines. PLC vendors have been vigilant about FCC Part 15 certification of all their equipment. As an industry, PLC has held that existing Part 15 standards are sufficient to regulate any interference that may be caused. But Alan Scrime, Chief of the Policy and Rules Division at OET, posed this question:
If you are doing everything right, and existing regulations are sufficient, why am I up here asking you questions?
Brett Kilbourne, Director of Regulatory Services for UPLC, had the answer:
Because there are incumbent users [of that spectrum] that you have a duty to protect.
In the PLC band of spectrum, there are established broadcast uses, including amateur radio and military applications such as radar, with which unregulated wire line services such as PLC may not interfere. And while Part 15 explicitly sets limits for point sources of radiation such as pieces of equipment, it does not address interference caused by a network of overhead or underground wires.
Speaking with Alan Scrime after the presentation, he made it clear that the FCC does not know of any PLC interference problems, has no wish to obstruct the growth of the industry. Yet, there is no denying that the heterogeneity of the power network makes it possible that some lines will unintentionally radiate the PLC signal, the cumulative effect of which is unknown. The FCC has no established procedure for measuring this radiation, and no limits to protect incumbent spectrum users. For months, said Alan, PLC vendors and organizations have promised to set up testing sites and report measurements. It has not happened, and with the industry progressing toward commercial deployment the FCC felt compelled to act. The proceeding is expected to begin this month, but has not yet been announced.
At the state level, a regulatory issue that continues to create uncertainty reached a milestone when the Pennsylvania Public Utility Commission (PUC) approved the affiliate transaction rules proposed by Pennsylvania Power and Light (PPL) and their subsidiary PPL Telecom. This was the first PLC proposal to be approved by a PUC. Since most electric utilities are regulated monopolies, there are state regulations governing their relationships with affiliate or subsidiary companies. State PUCs must rule on proposed agreements to ensure that the affiliate compensates the utility for the use of its assets--and that the utility passes any savings to consumers through its rates. While the regulations and disposition of the PUC will vary widely from state to state, this initial positive result will likely have a stabilizing effect as a kind of precedent.
Technology and Trials Updates

These sessions began with a revealing survey of the audience as to what type of company each person represented. The majority were from companies already involved in the PLC industry in some way, as a vendor or consultant. Small handfuls were from the press, government agencies, cable and telecom companies, and the smallest number, two, were there representing utilities interested in PLC. Perhaps the academic setting of the conference had something to do with it, but there did not seem to be a strong indicator of utility interest.
Amperion

Previously focused solely on providing backhaul over MV (medium voltage) power lines, Amperion now has developed and is trialing a Wi-Fi based consumer home solution. The data signal is injected into the MV power line from fiber, then passed from the MV to the LV (low voltage) lines via Wi Fi signaling. This satisfies the safety requirement of American Electric Power (AEP), one of Amperion's customers, that there be no wires connecting the MV to the LV lines around the transformer. This avoids any fault path between the high voltage of the MV regime, and low voltage of the LV regime.
Since, according to Amperion, 95% of people in the US live within 100s of meters of a transformer, they feel that they can use Wi Fi, rather than power lines, to get the signal into the home. In this way the CPE can be any Wi-Fi certified receiver.
Amperion currently is running trials with AEP in Dublin, OH, PPL in Allentown, PA, and a third utility whose name they haven't released yet. Results include MV data rates of 15-24 Mb/s, power line signal propagation good for around 2000 feet before a repeater is necessary, and 3-4 Mb/s per end user (Wi Fi throughput). They claim little latency, even with multiple receivers on the power line.
Install times are between 20 minutes and an hour for the power line equipment. However during the talk Jeff Tolnar, VP Marketing and Business Development for Amperion, mentioned that in the process of installs they had found anomalies in line performance, often requiring some troubleshooting. As the trials develop they are trying to develop the ability to pre-characterize lines. Jeff stated that so far their cost per house passed is between $50 and $150.
Main.net
Main.net is in trials in the US with the utilities Ameren, PPL, in Allentown, Pennsylvania, and APPA, in Manassas, Virginia. Main.net stated that during the last year they have expanded the size of the trials, signed an evaluation agreement with Southern Company, and released their second generation equipment.
Main.net has been very active outside the US as well, reporting activities in more than 40 countries, some with small commercial deployments. In Germany, their Manheim commercial offering with utility MVV now has 2000 homes, with 22,000 predicted by 2005. They expect to have infrastructure in place for 120,000 homes by end of this year. Main.net is also active in several South American countries, as well as India and Indonesia.
The Manassas trial has been active since May 2002, passes over 50 homes, and involves 15 users in homes and businesses. Data rates for users are 300 to 500 kb/sec at 2500 feet of power line. The Allentown trial with PPL passes over 1300 homes and currently involves around 300 homes. They estimated that the cost per house passed is around $160. Main.net has also found inconsistencies and attenuation in the power network, but stated that they are able to deal with them simply by adding repeaters.
Main.net stated that a US customer (most likely PPL) will begin offering commercial PLC service by the second half of this year.
Current Technologies

Joe Cufari, VP of Business Development for Current Communication Services, presented. Current actually has two companies--Current Technologies, which produces the PLC equipment, and Current Services, which creates joint ventures with utilities, and acts as a service provider to the consumers. In this way they hope to cover the range of potential utility customers. They anticipate that some will simply to purchase technology and act as their own service provider, while others will want a turn-key operation that is managed for them. Current also believes that acting as a service provider will make it easier to introduce utility services such as remote management, automated load balancing, and outage detection.
Current has two active trials in the US, with PEPCO in Maryland, and Cinergy in Ohio. Each trial passes more the 500 homes, with around 100 homes total signed up. The bandwidth to each home is between 2 - 4 Mb/sec symmetric. Since July have tested their technology, back office, repair, and support service and feels they are ready to go commercial.
Current has several "hooks" in its systems, looking to the future. First, Joe stated that Current builds its networks to carry voice, by limiting latency to less than 50 msec. Secondly, they will be able to tier service, perhaps at 256 kb/sec, 512 kb/sec, or 1 Mb/sec. Joe predicted cost parameters of $25.95 for 256kb/sec service, and $39.95 for 1.5 Mb/sec service, but they have not started charging yet. Joe stated that the economics work with 1.1 customers per transformer at first, 0.7 customers per transformer as capital costs decline over time.
PPL Telecom

This company provided a utility telecommunications subsidiary point of view. Like most utility telecom subsidiaries, PPL Telecom was built to leverage the extensive investment in fiber that PPL made along their main power networks. PPL Telecom offers fiber-based service to businesses. They believe PLC may be a way for them to leverage the fiber into the consumer market.
PPL Telecom uses both Main.net and Amperion technologies in trials currently. They are now past 1300 homes with Main.net, and several hundred with Amperion. Charles Boddy, Manager of Marketing, stated that implementation of Amperion's Wi-Fi solution has required significant troubleshooting. "Service means in the house, not in the yard."
PPL Telecom aims to provide total service--ISP as well as connectivity. During recent trials, they have focused on engaging their support systems more than testing the technology any further. They feel that these systems are more important than the technology for success, including customer care systems such as customer service, billing, support centers and systems, and fulfillment for equipment orders.
Based on their early trials, the Pennsylvania PUC has accepted their affiliate agreement and they will able to begin paying trials. They will most likely go with Main.net, starting later this year. PPL serves 1.3 million customers with electric power, but technical and economic issues will likely limit any PLC deployment to 700,00 to 800,000 of those.
Charles put it best:
Success is about availability, reliability, customer service, and trust. It's not always about technology.
The Business Case for PLC

As at the last CITI conference, several industry consultants presented analyses of the business case for PLC. Dr. Rahul Tongia of Carnegie Mellon University, and David Shpigler, President of the Shpigler Group, both presented analyses of the expected prices and penetration rates of PLC, in the larger context of the consumer broadband market. How much churn could PLC providers expect? What amount of market share or local penetration will be considered successful? While the numbers were fluid, and caused some heated exchanges, several important points came out of the discussions:
Rahul pointed out that PLC may be suffering from what he called the Parmenides Fallacy--comparing the expected future of PLC service to today's offerings of cable and DSL. But, he pointed that this was dangerous, since both cable and DSL are improving even as PLC is developing. Cable and DSL are likely to have higher performance for lower prices in the future.
David stated that until recently, the PLC industry was being driven by the vendors. Currently he sees that it is starting to change, with some utilities and service providers beginning to actively drive the development of the PLC industry. This is essential, since it will be these two constituencies that will drive consumer deployment and adoption.
Both David Shpigler and Charles Boddy of PPL Telecom emphasized the point that in PLC, operating expenses, not capital expenses, will represent the greatest costs. Recurring fixed costs include utility affiliate payments, upstream network costs, customer care systems, and marketing, all of which must be managed closely to achieve profitability.
The importance of strong management of operating expenses was emphasized by George Grabowich, VP of Business Development at Passport Corporation, and Antonia Townsend, VP of Marketing and Corporate Development at Fine Point Technologies. These are two companies that provide OSS systems to networks, and are looking to get involved with the PLC industry. Both offer a suite of services to utilities or their affiliate PLC service providers, to help manage the ongoing costs involved with rolling out and then managing a telecom network.
So what is the business case for PLC? As articulated during the roundtable discussion that closed the conference, both vendors and at least one utility subsidiary (PPL Telecom) believe that there are significant opportunities for PLC:
In areas that are not currently served, or are underserved by cable and DSL;
In 3rd and 4th tier markets where there may only be one option for broadband;
With people who are unhappy with their current Internet service, dial up or broadband; and
With people who are unhappy with the cost of other broadband services.
Most felt that it was very possible for PLC to co-exist with cable and DSL, and still succeed. As Charles Boddy stated:
I don't have to do it better than the incumbents; I just have to do it profitably.
Standards

Oleg Logvinov, President and COO of Enikia, titled his presentation "Lack of Standards Will Kill This Market." He believes that for PLC to succeed on a large scale, a standard for the interoperability of access equipment must be achieved. This will:
Eliminate uncertainty for utilities, by guaranteeing that they will not get stuck with one proprietary vendor;
Drive competition; and
Help keep operating expenses low.
Currently the only PLC standard is HomePlug, which was designed for in-home use only. Most the vendors are moving toward compatibility with HomePlug on their LV solution, and Current Technologies actually uses HomePlug for the whole LV side of their technology. In a talk after the conference, Oleg emphasized to us that sometimes specialization is good, and that in his opinion the demarcation point should still be the door of the house. HomePlug can provide for in-home interoperability for home networking, and the industry should develop a separate interoperability standard for access equipment. His model was the DOCSIS or Wi Fi programs, including full interoperability testing and certification.
HomePlug is not sitting still either, and the HomePlug Alliance is currently working on the next standard, to be called HomePlug AV. This is another in-home standard, intended to allow consumers to use the power lines in their house to pass audio/visual content around. Their goal is bandwidth greater than 20Mb/sec, with QoS sufficient to pass video or voice without latency or jitter.
Reply

#3


SUBMITTED BY
AKSHAY DHAR
DEPARTMENT OF ELECTRICAL ENGINEERING
MAHANT BACHITTAR SINGH COLLEGE OF ENGINEERING & TECHNOLOGY


[attachment=7933]

ABSTRACT
Over the past few years advances in signal processing technology have enabled the advent of modem chips that are able to overcome the transmission difficulties associated with sending communications signals over electrical power lines. In the United States, this capability has been termed Broadband over Power Lines or BPL. There are two predominant types of BPL communications configurations: Access BPL and In-Home BPL. Access BPL is comprised of injectors (used to inject High Frequency (HF) signals onto medium or low voltage power lines), extractors (used to retrieve these signals) and repeaters (used to regenerate signals to prevent attenuation losses). In addition to taking advantage of the power line infrastructure, In-Home BPL modems utilize the existing house wiring to provision a Local Area Network (LAN) that can be used throughout the home. One of the largest commercial markets for BPL is the ability to provide Internet Services by means of the Transmission Control Protocol/Internet Protocol (TCP/IP) protocols, which can support voice, data, and video services. Another significant benefit of BPL is the ability to employ intelligent power line networks that make use of Supervisory Control and Data Acquisition (SCADA) devices, dynamic provisioning, and other forms of modernized electrical power networks. A SCADA system can save time and money by reducing the need for service personnel to physically visit each site for inspection, data collection, and routine logging or even to make adjustments. The benefits also include the ability for real-time monitoring, system modifications, troubleshooting, increased equipment life, and automatic report generating.
The Federal Communications Commission (FCC) monitors approximately 59,000 frequencies for military, National Security & Emergency Preparedness (NS/EP), and other purposes. A key concern associated with BPL is that coupling of HF signals onto unshielded wiring, such as that used for outdoor power lines, may generate interference signals that could impact licensed services such as amateur radio, or hums . Public safety agencies including fire, police, the Red Cross and other agencies also depend on the use of the special propagation properties found only in the HF radio spectrum. This Technical report examines the architecture and considers possible benefits and concerns of BPL technology with respect to the National Communications System (NCS) and the communication requirements for NS/EP.

INTRODUCTION
Broadband over Power Lines (BPL) is a term used to describe the use of existing electrical lines to provide the medium for a high speed communications network. BPL, also known as Power Line Communications (PLC) is achieved by superimposing the voice or data signals onto the line carrier signal using Orthogonal Frequency Division Multiplexing.
There are two main categories of BPL: in-house and access. In-house BPL is broadband access within a building or structure using the electric lines of the structure to provide the network infrastructure. Home Plug (Home plug, 2005) is an alliance of several vendors of in-house BPL products which has authored a standard for device compliance. Products conforming to the Home Plug standard have been commercially available since 2002. For example, Linksys offers the PLEBR10 (Linksys, 2005), an adapter which connects an existing router (which accepts the in-coming broadband from Cable or DSL) to the electric lines of the house. Other computers in the building can then connect to the network simply by attaching their computer's network card to an adapter (e.g. Linksys PLUSB10) plugged into a wall outlet. Access BPL is the use of the electrical transmission lines to deliver broadband to the home. AccessBPL is considered a viable alternative to Cable or DSL to provide the 'final mile' of broadband to end users. A BPL coupler placed at the pole converts the transmission medium from fiber (originating at the substation) to medium voltage power lines. Broadband signals traverse the medium voltage power lines, bypassing transformers, with repeaters placed every mile along the transmission path. At the final pole, a BPL wireless device can deliver the broadband to home-installed BPL wireless receivers, or, the signal can be sent to the individual homes via the low-voltage electrical lines and made available through any BPL wired receiver.

Executive Summary
Despite the spread of broadband technology in the last few years, there are significant areas of theworld that don't have access to high-speed Internet. When weighed against the relatively small number of customers Internet providers would gain, the incremental expenditures of laying cable and building the necessary infrastructure to provide DSL or cable in many areas, especially rural, is too great. But if broadband could be served through power lines, there would be no need to build a new infrastructure. Anywhere there is electricity there could be broadband. Technology to deliver high-speed data over the existing electric power delivery network is closer to reality in the marketplace. Broadband overPower line is positioned to offer an alternative means of providing high-speed internet access, Voice over Internet Protocol (VoIP), and other broadband services, using medium and low voltage lines to reach customers homes and businesses. By combining the technological principles of radio, wireless networking, and modems, developers have created a way to send data over power lines and into homes at speeds between 500 kilobits and 3 megabits per second (equivalent to DSL and cable). By modifying the current power grids with specialized equipment, the BPL developers could partner with power companies and Internet service providers to bring broadband to everyone with access to electricity. The technology evolution in the next few years is important from a perspective of future competitive position of BPL as new networks are built and alternative technologies emerge. (See Table 3.5 for comparison of access technologies). Fiber and advanced wireless broadband are the new alternative broadband access systems that are most likely to emerge in the next few years. These could also become a part of an integrated BPL system. Federal policy support is also strengthening the potential for BPL deployment. The FCC and others have hailed BPL as a potential third wire that may help increase the availability and affordability of broadband services in a market dominated by digital subscriber line (DSL) and cable modem service. As part of the federal effort to remove barriers to BPL implementation, the FCC issued a change to Part 15 rules for measures to mitigate radio interference caused by broadband over power line. The FCC ruling on October 14, 2004 would essentially help to overcome BPL s potential to cause interference with radio and telecommunications signals. However, a number of jurisdictional and classification issues remain open. For example, are the broadband services offered via BPL considered an information service or a telecommunications service? This has implications since telecommunications services are subject to regulations under the Telecommunications Act of 1996, most notably common carrier requirements. As of October 2004, the FCC has two proceedings that address the issue of broadband regulatory classification: one deal with
cable modem services and another addressing all wire line broadband Internet access services generally. If classified as an information services, BPL service would be free frommany if not all common carrier regulations except, contribution to the universal service fund (USF). Reliability and safety of the power delivery system and provision of quality service are the main concerns for state commissions. In addition, affiliate transaction policies and cross subsidization issues are major concerns. State Commissions are obligated to prevent the unfair use of an asset developed with ratepayer funds for the benefit of shareholders. They are also obligated to ensure that electric utilities do not have an unfair advantage over competitors. Thus several solutions such as creation of unregulated BPL subsidiaries or implementation of accounting rules that guard against cross subsidization may be considered. The state regulators will also need to address rights of way, and access to poles issues. For instance, some municipalities may seek to charge fees for BPL rights of way. Pole attachment rules may also need to be addressed because of potential interference problems. The technical feasibility, the FCC rulemaking mitigating interference and the announcements of the commercial-scale tests of BPL have stimulated considerable interest in BPL among electric utilities, with several now evaluating deployment of BPL. The market trials and commercial deployments will reveal business case attractiveness of BPL compared to established DSL and cable services. However, there is also interest in BPL s potential to serve as a communications system that can support the network management of the power delivery system. The electric utilities will determine if the combined benefits of a system allowing for consumer telecom services, other consumer services, and core utility network communications help make the business model attractive for BPL. Utilities can consider applying three basic simplified business case models:
The Landlord Model leasing the conduit and assets to a third party, probably with amaintenance arrangement
The Developer Model a partnership or contract with an Internet service provider (ISP);the utility builds and owns the infrastructure, and the ISP handles all aspects of marketing, selling to and servicing the customer
The Service Provider Model utility manages the system, including serving as theInternet service provider
Each utility will assess BPL according to its own business objectives, risk tolerance, andprocedures. The factors to evaluate are cost, market size and price, differentiating features of BPL, bundled services and average revenue per user, and the utility applications.


Reply

#4


[attachment=7888]

SUBMITTED BY
AKSHAY DHAR
DEPARTMENT OF ELECTRICAL ENGINEERING
MAHANT BACHITTAR SINGH COLLEGE OF ENGINEERING & TECHNOLOGY.


ABSTRACT

Over the past few years advances in signal processing technology have enabled the advent of modem chips that are able to overcome the transmission difficulties associated with sending communications signals over electrical power lines. In the United States, this capability has been termed Broadband over Power Lines or BPL. There are two predominant types of BPL communications configurations: Access BPL and In-Home BPL. Access BPL is comprised of injectors (used to inject High Frequency (HF) signals onto medium or low voltage power lines), extractors (used to retrieve these signals) and repeaters (used to regenerate signals to prevent attenuation losses). In addition to taking advantage of the power line infrastructure, In-Home BPL modems utilize the existing house wiring to provision a Local Area Network (LAN) that can be used throughout the home. One of the largest commercial markets for BPL is the ability to provide Internet Services by means of the Transmission Control Protocol/Internet Protocol (TCP/IP) protocols, which can support voice, data, and video services. Another significant benefit of BPL is the ability to employ intelligent power line networks that make use of Supervisory Control and Data Acquisition (SCADA) devices, dynamic provisioning, and other forms of modernized electrical power networks. A SCADA system can save time and money by reducing the need for service personnel to physically visit each site for inspection, data collection, and routine logging or even to make adjustments. The benefits also include the ability for real-time monitoring, system modifications, troubleshooting, increased equipment life, and automatic report generating.
The Federal Communications Commission (FCC) monitors approximately 59,000 frequencies for military, National Security & Emergency Preparedness (NS/EP), and other purposes. A key concern associated with BPL is that coupling of HF signals onto unshielded wiring, such as that used for outdoor power lines, may generate interference signals that could impact licensed services such as amateur radio, or hums . Public safety agencies including fire, police, the Red Cross and other agencies also depend on the use of the special propagation properties found only in the HF radio spectrum. This Technical report examines the architecture and considers possible benefits and concerns of BPL technology with respect to the National Communications System (NCS) and the communication requirements for NS/EP.

INTRODUCTION
Broadband over Power Lines (BPL) is a term used to describe the use of existing electrical lines to provide the medium for a high speed communications network. BPL, also known as Power Line Communications (PLC) is achieved by superimposing the voice or data signals onto the line carrier signal using Orthogonal Frequency Division Multiplexing.
There are two main categories of BPL: in-house and access. In-house BPL is broadband access within a building or structure using the electric lines of the structure to provide the network infrastructure. Home Plug (Home plug, 2005) is an alliance of several vendors of in-house BPL products which has authored a standard for device compliance. Products conforming to the Home Plug standard have been commercially available since 2002. For example, Linksys offers the PLEBR10 (Linksys, 2005), an adapter which connects an existing router (which accepts the in-coming broadband from Cable or DSL) to the electric lines of the house. Other computers in the building can then connect to the network simply by attaching their computer's network card to an adapter (e.g. Linksys PLUSB10) plugged into a wall outlet. Access BPL is the use of the electrical transmission lines to deliver broadband to the home. AccessBPL is considered a viable alternative to Cable or DSL to provide the 'final mile' of broadband to end users. A BPL coupler placed at the pole converts the transmission medium from fiber (originating at the substation) to medium voltage power lines. Broadband signals traverse the medium voltage power lines, bypassing transformers, with repeaters placed every mile along the transmission path. At the final pole, a BPL wireless device can deliver the broadband to home-installed BPL wireless receivers, or, the signal can be sent to the individual homes via the low-voltage electrical lines and made available through any BPL wired receiver.

Executive Summary
Despite the spread of broadband technology in the last few years, there are significant areas of theworld that don't have access to high-speed Internet. When weighed against the relatively small number of customers Internet providers would gain, the incremental expenditures of laying cable and building the necessary infrastructure to provide DSL or cable in many areas, especially rural, is too great. But if broadband could be served through power lines, there would be no need to build a new infrastructure. Anywhere there is electricity there could be broadband. Technology to deliver high-speed data over the existing electric power delivery network is closer to reality in the marketplace. Broadband overPower line is positioned to offer an alternative means of providing high-speed internet access, Voice over Internet Protocol (VoIP), and other broadband services, using medium and low voltage lines to reach customers homes and businesses. By combining the technological principles of radio, wireless networking, and modems, developers have created a way to send data over power lines and into homes at speeds between 500 kilobits and 3 megabits per second (equivalent to DSL and cable). By modifying the current power grids with specialized equipment, the BPL developers could partner with power companies and Internet service providers to bring broadband to everyone with access to electricity. The technology evolution in the next few years is important from a perspective of future competitive position of BPL as new networks are built and alternative technologies emerge. (See Table 3.5 for comparison of access technologies). Fiber and advanced wireless broadband are the new alternative broadband access systems that are most likely to emerge in the next few years. These could also become a part of an integrated BPL system. Federal policy support is also strengthening the potential for BPL deployment. The FCC and others have hailed BPL as a potential third wire that may help increase the availability and affordability of broadband services in a market dominated by digital subscriber line (DSL) and cable modem service. As part of the federal effort to remove barriers to BPL implementation, the FCC issued a change to Part 15 rules for measures to mitigate radio interference caused by broadband over power line. The FCC ruling on October 14, 2004 would essentially help to overcome BPL s potential to cause interference with radio and telecommunications signals. However, a number of jurisdictional and classification issues remain open. For example, are the broadband services offered via BPL considered an information service or a telecommunications service? This has implications since telecommunications services are subject to regulations under the Telecommunications Act of 1996, most notably common carrier requirements. As of October 2004, the FCC has two proceedings that address the issue of broadband regulatory classification: one deal with cable modem services and another addressing all wire line broadband Internet access services generally. If classified as an information services, BPL service would be free frommany if not all common carrier regulations except, contribution to the universal service fund (USF). Reliability and safety of the power delivery system and provision of quality service are the main concerns for state commissions. In addition, affiliate transaction policies and cross subsidization issues are major concerns. State Commissions are obligated to prevent the unfair use of an asset developed with ratepayer funds for the benefit of shareholders. They are also obligated to ensure that electric utilities do not have an unfair advantage over competitors. Thus several solutions such as creation of unregulated BPL subsidiaries or implementation of accounting rules that guard against cross subsidization may be considered. The state regulators will also need to address rights of way, and access to poles issues. For instance, some municipalities may seek to charge fees for BPL rights of way. Pole attachment rules may also need to be addressed because of potential interference problems. The technical feasibility, the FCC rulemaking mitigating interference and the announcements of the commercial-scale tests of BPL have stimulated considerable interest in BPL among electric utilities, with several now evaluating deployment of BPL. The market trials and commercial deployments will reveal business case attractiveness of BPL compared to established DSL and cable services. However, there is also interest in BPL s potential to serve as a communications system that can support the network management of the power delivery system. The electric utilities will determine if the combined benefits of a system allowing for consumer telecom services, other consumer services, and core utility network communications help make the business model attractive for BPL. Utilities can consider applying three basic simplified business case models:
The Landlord Model leasing the conduit and assets to a third party, probably with amaintenance arrangement
The Developer Model a partnership or contract with an Internet service provider (ISP);the utility builds and owns the infrastructure, and the ISP handles all aspects of marketing, selling to and servicing the customer
The Service Provider Model utility manages the system, including serving as theInternet service provider
Each utility will assess BPL according to its own business objectives, risk tolerance, andprocedures. The factors to evaluate are cost, market size and price, differentiating features of BPL, bundled services and average revenue per user, and the utility applications.


Reply

#5
[attachment=3736]

WELCOME TO THE PRESENTATION

Broadband Over Power Line


Introduction


Broadband over Power Line (BPL) is a
technology that allows Internet data to be transmitted over utility power lines.

In order to make use of BPL, subscribers use neither a phone, cable nor a satellite connection.

Instead, a subscriber installs a modem that plugs into an ordinary wall outlet and pays a subscription fee similar to those paid for other types of Internet service
They travel along the wires and pass through the utility transformers to subscribers' homes and businesses. Little, if any, modification is necessary to the utility grid to allow transmission of BPL
The Federal Communications Commission (FCC) is currently working on a set of rules according to which BPL may be implemented in the United States. Power line communications uses the RF signal sent over medium and low voltage AC power lines to allow end users to connect to the Internet.
The RF signal is modulated with digital information that is converted by an interface in the home or small business into Ethernet compatible data

Block diagram of BPL

Closeview of household



BPL Modem Connection

The Power Grid


To gain a good understanding of how PLC Works an excellent understanding of the Power Grid is required.
Unlike telephony and it's associated technologies there is no set standard for providing power
Power is generated at Power stations and distributed around a medium to large geographical area via HV lines or High Voltage lines
At the customer's house or premises a transformer is used to drop the voltage down to safer more manageable voltages for use in the home or business.
This power is usually transported over LV or Low Voltage lines. These Low Voltage Lines include the lines that traverse a customer's home or business

PLC Encoding

PLC is based on the idea that any copper medium will transport any electrical signal for a certain distance.

Basically a radio signal is modulated with the data we wish to send.

This radio signal is then sent down the copper medium (our power lines) in a band of frequencies not used by for the purposes of supplying electricity and managing electricity
PLC backbones

PLC Into the Home


There are two means of getting the broadband into the home from the electrical pole.

One method is to use a wireless device located on the power line to broadcast a radio signal containing the data with a receiver located in the home.

This method allows "In Home" PLC to be used to network machines such as printers PCs and other PLC enabled devices.

The alternative is to allow the PLC frequencies to either skip around or pass through the transformer and continue onto the home allowing any devices with PLC connections to be plugged in anywhere in the home



Shows In-building BPL

Categories of PLC or BPL


In-building BPL

These BPL systems use the buildings electrical wiring to network computers within a building.
Most operate under the Home Plug specification.
An example of a company that offers Home Plug is Maxim's Power line products that are based over in the U.S.
This company uses the Home Plug standard to turn ordinary AC power wiring into a data and multimedia network.
It offers 14Mbps data transfer rates over existing electrical wiring in the home or office
Access BPL

Access BPL uses electrical distribution lines, overhead or underground, to provide broadband Internet access to homes and businesses.

These access BPL systems serve as a significant interference potential to over the air radio services such as the American Radio Relay League (ARRL) and the U.S. Federal Emergency Management Agency (FEMA).

Multiple Formats of Access BPL

End-to-End Access BPL

Figure It Overview of End-to-End Access BPL Svstem

Hybrid Access BPL

History


The first technique to make use of the power line for control messages was the method - Ripple Control.

This is characterised by the use of low frequencies (100 - 900Hz) giving a low bit rate and a demand on very high transmitter power, often in the region of several 10kWs

In the mid 1980's experiments on higher frequencies were carried out to analyse the characteristic properties of the electric grid as a medium for data transfer

Bi-directional communication was developed in the late 80's and early 1990's and the main difference between these systems and modern systems today is that much higher frequencies and a substantial reduction of the signal levels are used on today's power grid network

Industry Players in PLC
Power Line Communications Association United Power Line Council PLC Forum HomePlug Alliance

Advantages

Power line communications opens up many new business opportunities for applications and customer services, for both telecom and electricity sectors in Europe and in the U.S.

There are various strong, unique advantages for PLC to become a very important element in the future of broadband communications.

Power line communications provides many advantages for the providers of the service and also more importantly for the end users of the service

A major selling point for the development of PLC for utility companies is that most of the infrastructure is already in place because the technology relies on the existing power grid
The equipment needed to set-up PLC in the home in the U.S. is cheaper on average that that of other broadband solutions such as DSL and cable modem, usually costing (depending on equipment) between $45 up to $75
The equipment uses existing power outlets in the home making it a lot easier to set-up and also is very simple to set-up as it is plug and play
Power line communications outperforms its competitors with speeds of up to 14Mbps. For users in rural areas, who cannot receive DSL or cable modem services, PLC can be used to provide an all in one service providing telephone, cable television and high speed data

Disadvantages



Access BPL systems are designed to send information within parts of the 2-80 MHz frequency range along unshielded power lines, which results in the unintended emission of RF energy.

This unintentional radiation can create interference to the radiocommunication services mentioned above
Future
Standardisation of BPL technology to allow better deployment of BPL equipment

Cost of BPL needs to become more competitive in the broadband market

Interference issues needs to be resolved to prevent conflicts of interest between government and radio enthusiasts

The marketing of BPL needs to be performed to a high standard in order to make consumers aware of this technology
Conclusion

There are many examples of power line communications projects worldwide, ranging from R&D projects to Internet Service Provider (ISP's) commercial introductions of power line communications.
PLC has taken off in the UK, Germany and also in
the U.S.
The latest news on power line networking in the U.S. is that the Federal Communications Commission (FCC) has moved forward with a process to measure interference caused by the broadband over power line service.
Federal Emergency Management Agency (FEMA) have expressed concerns over the unlicensed broadband over power line equipment interfering with their licensed radio signals.

However, the FCC staff are confident that the interference problems can be resolved.

The FCC sees broadband over power lines as a potential competitor to digital subscriber line (DSL) and cable modem services.

They also see broadband over power lines providing broadband access to places not served by cable or DSL

Thank You
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#6
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Broadband over power lines (BPL), also known as power-line Internet or powerband, Broadband over Power Lines, or BPL, refers to the transmission (sending and receiving) of digital data through existing power cables and electricity distribution infrastructures. 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. The key to broadband over power lines (Broadband over Power Lines) technology lies in a long established scientific fact: radio frequency (RF) energy can be bundled on the same line that carries electrical current. Since RF and electricity vibrate on different frequencies, there's not going to be any interference between the two. As such, data packets transmitted over RF frequencies are not overwhelmed or lost because of electrical current., Deployment of BPL has illustrated a number of inherent challenges. The primary one is 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). 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 predictable problems including security, limited maximum throughput and inability to power devices efficiently. 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.

read more
http://computer.howstuffworksbpl.htm
http://en.wikipediawiki/Power_line_commu...erlines.29
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#7
Broadband over Power Lines
The recent advances in signal processing technology have enabled the advent of modem chips that are able to overcome the transmission difficulties associated with sending communications signals over electrical power lines. Access BPL and In-Home BPL are the two variants of the Broadband over power lines technology. Access BPL is comprised of:
-injectors (used to inject High Frequency (HF) signals onto medium or low voltage power lines)
-extractors (used to retrieve these signals)
-repeaters (used to regenerate signals to prevent attenuation losses)

The In-Home BPL modems utilize the existing house wiring to provision a Local Area Network (LAN). BPL can provide internet access through the Transmission Control Protocol/Internet Protocol(TCP/IP) and can support voice, data, and video services. Supervisory Control and Data Acquisition (SCADA)i devices, dynamic provisioning, and other forms of modernized electrical power networks can be utilized by it.

BPL Overview:
The development of sophisticated modulation, encoding, and error correction schemes along with much faster DSP techniques as made possible the low-power designs for carrier current devices. spread spectrum or multiple carrier techniques can be made use of. turbo code tecniques such as the concatenated Reed-Solomon Forward Error Correction, convolutional coding employing the Viterbi algorithm etc can also be put to use.

Power Line Infrastructure:
the in-place electrical power grid is made use of by BPL. The electric utilities have been using various gauge aluminum-conductors, steel-reinforced cables for electric power distribution. Electric power line cables have been optimized for an average transmission of power of 50-60 hertz (Hz) and a maximum in the range of 400 Hz.

Power Line Characteristics
The major challenges posed by the electrical lines are:
-large attenuation
-electrically contaminated
-lines are made of variety of materials and cross sections are joined almost at random
-characteristic impedances varies widely

HF signals can be injected onto a power line by using an appropriately designed high pass filter. Received signal power will be maximized when the impedance of the transmitter, power line and the receiver are matched.

For more details, refer these pdf:
ncs.gov/library/tech_bulletins/2007/tib_07-01.pdf
mydocs.epridocs/public/000000000001011264.pdf
state.nj.us/rpa/BPLwhitepaper.pdf
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#8
Fast Internet access is growing from a convenience into a necessity in all aspects of our daily lives. Unfortunately, this has been held back by the high expenses of wiring infrastructure essential to deliver such high-speed internet access especially to private homes, small offices and rural areas, where the installation of any kind of new wires tilts the scales of the economic feasibility to a non-profitable state. This problem is known as the last mile problem which has been an active area of research throughout research community.
But if broadband could be served through power lines, there would be no need to build a new infrastructure. Anywhere there is electricity there could be broadband. Broadband over Power Line (BPL) is a technology which allows transmission of data over the same lines used to transmit electrical power. Through signal modulation of existing power, electrical utilities can transmit low frequency signals at 50 Hz to 60 Hz (normal alternating current [AC] power) and higher frequency signals (data) above 1 MHz without any mutual interference. Power line communications uses the radio frequency (RF) signal sent over medium and low voltage AC power lines to allow end users to connect to the Internet. The RF signal is modulated with digital information that is converted by a modem in the home or small business into Ethernet-compatible data.
Historically, power utilities have used alternating current (AC) power line distribution facilities to carry information by coupling radio frequency (RF) energy to AC electrical wiring in houses or buildings. In the past, these devices have operated on frequencies below 2 MHz with limited communications capabilities. Due to power line characteristics it has been difficult to achieve dependable high-speed communications. However, technological advancements have resulted in the development of new systems which have overcome these technical obstacles. Trials have demonstrated that high-speed communication voice and data services can be achieved using the existing medium-voltage (MV) and low-voltage (LV) power distribution grid.
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#9
Fast Internet access is growing from a convenience into a necessity in all aspects of our daily lives. Unfortunately, this has been held back by the high expenses of wiring infrastructure essential to deliver such high-speed internet access especially to private homes, small offices and rural areas, where the installation of any kind of new wires tilts the scales of the economic feasibility to a non-profitable state. This problem is known as the ?last mile problem? which has been an active area of research throughout research community.

But if broadband could be served through power lines, there would be no need to build a new infrastructure. Anywhere there is electricity there could be broadband. Broadband over Power Line (BPL) is a technology which allows transmission of data over the same lines used to transmit electrical power. Through signal modulation of existing power, electrical utilities can transmit low frequency signals at 50 Hz to 60 Hz (normal alternating current [AC] power) and higher frequency signals (data) above 1 MHz without any mutual interference. Power line communications uses the radio frequency (RF) signal sent over medium and low voltage AC power lines to allow end users to connect to the Internet. The RF signal is modulated with digital information that is converted by a modem in the home or small business into Ethernet-compatible data.

Historically, power utilities have used alternating current (AC) power line distribution facilities to carry information by coupling radio frequency (RF) energy to AC electrical wiring in houses or buildings. In the past, these devices have operated on frequencies below 2 MHz with limited communications capabilities. Due to power line characteristics it has been difficult to achieve dependable high-speed communications. However, technological advancements have resulted in the development of new systems which have overcome these technical obstacles. Trials have demonstrated that high-speed communication voice and data services can be achieved using the existing medium-voltage (MV) and low-voltage (LV) power distribution grid.
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#10
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[attachment=6767]

Broadband over Power Lines (BPL)

INTRODUCTION

Broadband over Power Lines (BPL) is a term used to describe the use of existing electrical lines to provide the medium for a high speed communications network. BPL, also known as Power Line Communications (PLC) is achieved by superimposing the voice or data signals onto the line carrier signal using Orthogonal Frequency Division Multiplexing.
There are two main categories of BPL: in-house and access. In-house BPL is broadband access within a building or structure using the electric lines of the structure to provide the network infrastructure. HomePlug (Homeplug, 2005) is an alliance of several vendors of in-house BPL products which has authored a standard for device compliance. Products conforming to the HomePlug standard have been commercially available since 2002. For example, Linksys offers the PLEBR10 (Linksys, 2005), an adapter which connects an existing router (which accepts the in-coming broadband from Cable or DSL) to the electric lines of the house. Other computers in the building can then connect to the network simply by attaching their computer's network card to an adapter (e.g. Linksys PLUSB10) plugged into a wall outlet.
Access BPL is the use of the electrical transmission lines to deliver broadband to the home. Access
BPL is considered a viable alternative to Cable or DSL to provide the 'final mile' of broadband to end users. A BPL coupler placed at the pole converts the transmission medium from fiber (originating at the substation) to medium voltage power lines. Broadband signals traverse the medium voltage power lines, bypassing transformers, with repeaters placed every mile along the transmission path. At the final pole, a
BPL wireless device can deliver the broadband to home-installed BPL wireless receivers, or, the signal can be sent to the individual homes via the low-voltage electrical lines and made available through any BPL wired receiver.
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