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There are many ways to deliver broadband services for Internet access and utility applications and grid automation ("smart grid"). Although any technology can cause interference under some circumstances, the alternatives to BPL have not been shown to have the serious, widespread interference problems associated with many of the BPL trials attempted to date. This page describes alternative technologies that should be considered by electric utilities, municipalities and neighbors as they choose broadband alternatives. This is an opportunity for local Amateurs to educate their local utilities and governments on lower (or non) interference systems, often with higher speed and capacity, increased reliability and even lower cost.
These alternatives generally do not have the problems of interference both from and to BPL. (BPL can be implemented without harmful interference to Amateur Radio if each part of the system is carefully adjusted to comply with the applicable emissions limits and state-of-the-art notching (-35 dB) is implemented, with guard bands included to protect the Amateur band edges.) Notching can be applied to protect other spectrum as well, although in the US, in most systems, only the Amateur bands are geneally notched.
The modernization of the electric power grid, often called "smart grid" by its proponents, is an important goal. Techniques such as Advanced Metering Infrastructure (AMI), Automated Meter Reading (AMR) and intelligent grid management can all be integrated into a smart-grid application. Having better control of the power grid will improve its reliability and efficiency and, as applications are developed for end users, point-of-use monitoring and control of power usage will benefit utilities by reducing peak loads and benefit consumers by providing a way to save on electrical-energy costs.
In grid-automation applications, the control system is the core of the design, with the backbone used to allow the equipment in that system to communicate a secondary requirement. This backbone can be accomplished a number of ways, each with its advantages and disadvantages. A white paper, "Electric Utility Communications, Applications and Smart Grid Technologies," describes grid modernization and the various technologies that are being used to implement it. It is a generally accepted engineering principle, however, that control of a system should be designed to be as independent of that system as possible, to ensure that system failures (ie, power outages) do not also result in loss of control of the system at a time when control may be needed the most.
Many of the techniques used to send information to and from the power grid have been shown to avoid widespread inteference problems. BPL can and does play a role in grid automation, especially for the in-premise part of these systems. If an electric utility is implmenting grid automation, this does not necessarily mean that there will be interference. If a utility uses a technology that does not cause interference, or it it carefully adjusts each component of a BPL system to operate at the correct power levels with notching for the Amateur bands, grid automation can operate without widespread interference problems.
BPL: 5Mb/s max (650kb/s - 1Mb/s typically available due to overhead)
DSL: 1.1Mb/s shared, 800kb/s downstream and 300kb/s upstream (usually half this available)
Cable: 500kb/s - 10 Mb/s (shared, depends on loading)
Fiber to the home (FTTH): 1Gb/s (limited availability, high cost)
Satellite:
WiFi: 11Mb/s (typically half that and depends on signal strength)
WiMAX: 75Mb/s max (probably less than half that available)
Wireless telephone:
DSL uses various digital modulation schemes to adaptively fill the available bandwidth of a standard twisted pair phone line. Typically, DSL makes use of bandwidth above 3kHz, leaving the lower bandwidth for standard voice telephone. To learn more:
DSL Forum tutorial on DSL
http://www.dslforum.org/about_dsl.htm?page=aboutdsl/IForums.html
Links about DSL:
Wikipedia explanation of ADSL
http://en.wikipedia.org/wiki/ADSL
ADSL is a newer DSL standard that uses OFDM modulation and provides adaptive asymetrical performance where upstream and downstream data rates are different.
VDSL2 tutorial: (DSL Forum, 2005) www.dslforum.org/learndsl/ppt/VDSL2_Tutorial-2005.ppt
VDSL2 article: (May 4, 2006) http://www.lightreading.com/document.asp?doc_id=93103&page_number=1&site
Cable providers use two or more standard 6MHz analog TV channels to carry a digitally modulated signal. Cable is second only to optical fiber in the amount of raw bandwidth available.
http://computer.howstuffworks.com/cable-modem2.htm
Cable now passes 105 million US homes, of which 21% are connected.
See http://www.ncta.com/Docs/PageContent.cfm?pageID=86.
WiFi
WiFi , also known as 802.11x, refers to an IEEE standard detailing a wireless network protocol. Originally designed for wireless home and small business networking, it has been enhanced and adapted to an outdoor environment. For a tutorial on WiFi see http://www.wi-fiplanet.com/tutorials/article.php/1216351.
EarthLink to Sell Off its Muni Wi-Fi Business -- Wi-Fi Planet, February 8, 2008
Last November, EarthLink announced it would not make any further “significant investments” in its muni wireless business and that it would “begin a process to consider its strategic alternatives.” Yesterday, the company announced that the alternative it has settled on is to sell off the business altogether.
Municipal Broadband: Demystifying Wireless and Fiber-Optic Options -- New Rules Project, January, 2008
The United States, creator of the Internet, increasingly lags in access to it. In the absence of a national broadband strategy, many communities have invested in broadband infrastructure, especially wireless broadband, to offer broadband choices to their residents. Newspaper headlines rumpeting the death of municipal wireless networks ignore the increasing investments by cities in Wi-Fi systems. At the same time, the wireless focus by others diverts resources and action away from building the necessary long term foundation for high speed information: fiber optic networks.
Why WiFi Networks are Floundering - BusinessWeek, Olga Kharif, August 15, 2007
The road is getting bumpier for cities and the companies they have partnered with in a bid to blanket their streets with high-speed Internet access at little or no cost to users. While 415 U.S. cities and counties are now building or planning to build municipal Wi-Fi networks, "deployments are slowing down slightly," says Esme Vos, founder of consultancy MuniWireless.com.
Telecom Ottawa is more excited about its Wi-Fi initiatives than BPL:
http://www.wi-fiplanet.com/columns/article.php/3485491
WiMax
WiMax is an improved microwave wireless protocol. It was intentionally designed to provide mesh and backhaul capabilities and overcomes many of the problems associated with 802.11 "hot spot" implementations.
"FCC Considers Offering Spectrum for Free Wireless Internet" IDG News Service - Nancy Gohring (May 2008)
The U.S. Federal Communications Commission will soon vote on a plan to auction spectrum, with the winner required to offer free wireless Internet services in the 2155MHz band. The operator could choose to use any technology, but in that range WiMAX or many of the mobile technologies would make sense.
"FCC Weighs Free-Internet Plan" The Wall Street Journal - Amy Schatz (May 2008)
In the quest to increase Americans' access to broadband Internet, federal regulators are considering a new plan: get someone to give it away free. The Federal Communications Commission is considering a plan that would require the winner of a planned airwaves auction to offer free wireless-Internet service to most Americans within the next few years.
Australian WiMAX pioneer trashes technology as "miserable failure" CommsDay Australasia - Grahame Lynch (March, 2008)
Australia’s first WiMAX operator, Hervey Bay’s Buzz Broadband, has closed its network, with the CEO labeling the technology as a “disaster” that “failed miserably.” In an astonishing tirade to an international WiMAX conference audience in Bangkok, CEO Garth Freeman slammed the technology, saying its non-line of sight performance was “non-existent” beyond just 2 kilometres from the base station, indoor performance decayed at just 400m and that latency rates reached as high as 1000 milliseconds. Poor latency and jitter made it unacceptable for many Internet applications and specifically VoIP, the main selling point to induce people to shed their use of incumbent services.
"Winner: Sprint's Broadband Gamble" IEEE Spectrum Online - Steven Cherry (January 2008)
Eventually, Sprint officials hope to lure entire industries. For example, gas and electric companies typically build large-scale communications networks to monitor their sprawling distribution networks. According to Warren Causey, vice president of Sierra Energy Group, Xohm “offers utilities the advantage of no longer having to manage complex wireless networks.”
The link between WiMax and small business is explored in this article:
http://smallbusiness.itworld.com/4384/featurelink_wiresmb050309/page_1.html
Plainfield, VT is planning to use WiMax in an area wide broadband service:
http://www.boston.com/news/local/vermont/articles/2005/02/17/rural_broadband_coming_to_plainfield_marshfield_area
Internationally, WiMax is making inroads in China:
http://www.adaptix.com/content/files/020805_Beijing_Airways.pdf
and in the UK:
http://news.bbc.co.uk/go/em/fr/-/1/hi/technology/4462167.stm
Mesh networks use an array of WiFi or WiMax routers, typically mounted on street lights and power poles to provide high-speed self-configuring access over a wide area. WiFi or ZigBee bridges can enable network users or meters, loads and thermostats to communicate and be controlled.
Despite the challenges that come with upgrading a wireless system, substantial cost and operational improvements can be achieved by investing in wireless technologies that support new applications while simplifying network and application integration. UTC's newest research paper, New Wireless Technologies for Utilities, looks more closely at three advanced wireless technologies - WiMAX, Radio-IP, and mesh networking.
Tutorials about Mesh Networks
Here is a tutorial on how mesh networks function:
http://www.wi-fitechnology.com/Wi-Fi_Reports_and_Papers/History_of_Wi-Fi_Mesh_Networks.html
Cisco recently released it's Mesh Technology:
http://rfdesign.com/ar/cisco-mesh-backbone/
http://www.crn.com/sections/breakingnews/breakingnews.jhtml?articleId=173600541
More on mesh from Microsoft:
http://research.microsoft.com/mesh/
Articles about Mesh Networks:
Tropos MetroMesh Proven: Metro-Scale WiFi in Chaska, MN:
http://www.tropos.com/pdf/chaska_performance.pdf
February 1, 2005, Tropos.com -- This white paper describes a successful mesh network in Chaska, MN.
Mesh networks are also proving popular in ad hoc military, public service and emergency service:
http://www.motorola.com/governmentandenterprise/northamerica/en-us/public/functions/browseproduct/productservices.aspx?navigationpath=id_804i
Other Links about Mesh Neworks
Mesh networks, sometimes combined with other technology has led to a boom in Metro WiFi implementation, turning whole towns or even small countries into WiFi "hot spots".
Metro WiFi in Sunnyvale:
http://www.siliconvalley.com/mld/siliconvalley/13319065.htm
Metro WiFi in Philadelphia:
http://news.bbc.co.uk/1/hi/programmes/click_online/4491506.stm
Metro WiFi in Racine, WI:
http://muniwireless.com/municipal/projects/939
Nationwide WiFi in Macedonia:
http://www.wi-fiplanet.com/news/article.php/3565381
Metro WiFi in Mountain View:
http://www.mercurynews.com/mld/mercurynews/business/technology/13182596.htm
Intel Announces RCP Platform for Rural Internet Access -- Daily Tech, March 19, 2008
Internet connectivity is taken for granted by those who live in cites with well-established infrastructures for cable and telephone networks. However, in many rural areas of the U.S. and in developing countries, Internet access either doesn’t exist or is only available as dial up that lacks the bandwidth needed for modern applications. Intel announced plans today for a platform that will allow WiFi in remote locations as far as 60 miles away at broadband speeds of up to 6.5 megabits per second.
Municipal Broadband: Demystifying Wireless and Fiber-Optic Options -- New Rules Project, January, 2008
The United States, creator of the Internet, increasingly lags in access to it. In the absence of a national broadband strategy, many communities have invested in broadband infrastructure, especially wireless broadband, to offer broadband choices to their residents. Newspaper headlines rumpeting the death of municipal wireless networks ignore the increasing investments by cities in Wi-Fi systems. At the same time, the wireless focus by others diverts resources and action away from building the necessary long term foundation for high speed information: fiber optic networks.
Here is an IEEE paper on providing gigabit throughputs on fiber and wireless:
http://www.ieeeusa.org/volunteers/committees/ccip/docs/Gigabit-WP.pdf
In the past, satellite broadband was pretty much one way, with satellite being used to provide downstream service to an end user and dialup usually used to provide slower upstream service back from that user. Today's satellite technology, however, generally runs broadband in both directions, available to urban and rural areas equally. A partial (alphabetical) listing of major satellite internet services:
Covad Wireless
HughesNet
My Blue Dish
Skycasters
StarBand
WildBlue
See the various FAQs on satellite broadband:
http://en.wikipedia.org/wiki/Satellite_Internet_access
http://computer.howstuffworks.com/question606.htm
Satellite broadband for rural areas:
This article describes how broadband was brought to a rural community in Ohio, using satellite broadband.
Technology Improvements
Higher speeds on existing media
Advances permitting higher data rates on one media can often be applied to other medias, particularly if the other medias have higher raw capacity.
Propagating Wave on a Single Conductor
6/20/2009 -- This white paper gives an introduction to the theory, practice and applications of the surface wave propagation that underlies this new technology. It gives some details of propagation on typical overhead power lines as well as some information about the characteristics of common impairments. There is also a comparison of this technology with other last mile pipes, including radio/wireless, CATV, DSL and BPL.
CableLabs is working on technology that will let cable operators boost speeds 400% to 1,600%, over their existing lines http://www.usatoday.com/tech/news/2005-04-05-speed-usat_x.htm
270MB/s over coax cable is already hitting home applications
http://www.eet.com/news/latest/showArticle.jhtml?sssdmh=dm4.162541&articleID=175801344
We sometimes lose sight of the fact that the internet is just that, the interconnection of otherwise independent networks. By following the same standards, networks can communicate with each other, much the same way amateurs can communicate the world over by CW. A mixed technology network would use a combination of all of the above technologies to solve the unique requirements of delivering broadband connectivity.
Motorola has introduced a mixed technology network that uses a "better BPL". http://www.motorola.com/mediacenter/news/detailpf/0,,5519_5509_23,00.html This system teams up the Motorola Canopy wireless solution with a HomePlug low voltage system. The Motorola version of HomePlug has hardware filters for the amateur bands.
Motorola Powerline LV brochure:
http://www.motorola.com/Enterprise/contentdir/en_US/Enterprise/Files/PLV_Brochure.pdf
Green Mountain State to pilot 4G system for statewide broadband
8/10/2007, Mass High Tech, Efrain Viscarolasaga - Vermont officials say they've inked a deal -- aimed at becoming the first "e-state" by 2010 -- that would allow the state to be the first to test a combined satellite and terrestrial wireless network. The new network, being developed by Virginia-based TerreStar Networks Inc., would bring a fourth generation (4G) terrestrial network to Vermont, augmented by satellite communications, to deliver coverage even to hard-to-reach rural areas, such as the 2,000-square-mile northernmost area of the state known as the Northeast Kingdom.
P1777 - http://standards.
ieee.org/ announcements/ pr_P1777new. html
IEEE P1777 will evaluate the potential of wireless technologies in power systems to determine where they are viable alternatives to wired systems and what further development they need in order to meet robustness, security and reliability and other requirements. The standard will explore the potential uses of wireless technologies at many levels of power system operations, including substations, underground vaults, transmission and distribution circuits, generation and distributed generation plants, and customer electrical and metering equipment.
BPL Not Ready for Prime Time Smart Grid
October 1, 2009, PowerGrid International - This article, written by the CEO of a major BPL/Smart Grid company, accurately describes some of the financial and interference aspects of BPL technology. Electric utility companies are looking for sound information relating to the nascent Smart Grid technology. This issue of PowerGrid focuses on a number of aspects of the developing Smart Grid. Scroll down to page 43 for the article on BPL. "BPL does not perform well in the overhead U.S. electrical distribution topology, and thus today a BPL signal cannot communicate over long distances or through a transformer without couplers and repeaters to boost the signal. This additional equipment increases overall deployment costs and eliminates cost savings associated with using the existing wires. . . There are further problems in transmitting BPL signals over power lines, including interference issues caused and experienced by a BPL system. Overhead electrical distribution wires are unshielded from radio frequency (RF) interference, therefore, BPL signals traveling on medium-voltage overhead lines have the potential to interfere with shortwave radio operators. Local RF using unlicensed spectrum also can interfere with the BPL network signal, and because the spectrum is unlicensed, mitigation can be timely and costly."
33 Million To Have 10Mbps By 2012
3/4/2008 -- DSL Reports
The nation's other 270 million apparently aren't so lucky... According to a new pay report by Parks Associates, 33 million of the nation's 300,500,000 residents will have access to 10Mbps broadband by 2012. Obviously the majority of customers will be somewhere around 3-7Mbps -- and the FCC's official classification of what constitutes broadband remains a paltry 200kbps.
Top 22 U.S. ISPs by Subscriber: Q3 2006
1/1/2007 -- ISP Planet
The top 22 ISPs are listed. First Communications, involved in both DSL and in-premise BPL, is #22, with 0.1% of the total market share. The report does not cite what percentage of their business is BPL, but they do not appear in the industry access BPL database, so their involvement is entirely within building.
Metro Fiber Optic Leader Predicts Minimum 200 Megabits Online Speeds Following Korea and Japan Models
12/13/2006 -- Government Technology -- "Rusin also discounts claims leading to Broadband over Power Lines as a mass market IP medium as having guaranteed limitations. Though power lines are ubiquitous, they are also made of copper. BPL trials conducted so far have been inconclusive. A byproduct of these early trials has seen several early adopters exiting the technology. Anecdotally, the limited BPL results have a few BPL providers now over-building the power grid with fiber. If BPL was viable -- why would you fiber the power grid? In addition, if you are going to fiber the power grid, it would make more sense to offer wi-fi or WiMAX and wireless backhaul which has a greater bandwidth capacity, albeit not close to fiber, but greater than power distribution copper. BPL is the ISDN of the new millennium -- lots of promise theoretically -- a niche market at best."
