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Broadband over Power lines. by Jayesh Chi Bun Mummoorthy CS 536 – October 22, 2004. Broadband over power lines (BPL). FCC approved last week: power utilities free to carry data on electrical wires to provide broadband services Benefits
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Broadband over Power lines by Jayesh Chi Bun Mummoorthy CS 536 – October 22, 2004
Broadband over power lines (BPL) • FCC approved last week: power utilities free to carry data on electrical wires to provide broadband services • Benefits • Better coverage than phone and cable (e.g. small towns and rural areas) • Faster deployment • May lower the price • Challenges • EM interference to various radio signals • System to monitor interference, • Restrict service in areas where could affect public safety • High-voltage and fluctuation can corrupt data • Clean data stream if power down to 7000V
How Stuff Works? • Medium • Fibers / Phone lines (to skip disruptive high-voltage lines) • Medium voltage wires • PHY • RF (bundled w/ AC) • 4.3MHz – 20.9MHz • 84 carriers • OFDM • MAC • CSMA/CA • virtual carrier sense • contention resolution • Encoding: DQPSK • Error detection/correction: FEC, ARQ
How Stuff Connected? • How to plug in? • Wireless router on poles • Special adaptor/modem plugged into electrical outlets • Data rates • Homeplug Powerline Alliance: 14Mbps • Amperion: currently 20Mbps, 100Mbps next year • CVEC: claims 256Mbps bidirectionally • Prices • Amperion: $19/mo • Home n/w device: $25 Wall-plugged Ethernet Bridge
The future • Home network • Easily create a network via electric outlets • Smart electrical grids and devices • Read electrical usage • Diagnose maintenance problems and feed back • Traffic lights, surveillance cams networked instantly • Control power use
Comments on the article & the topic • Pros • Impact of BPL to broadband providers • Provided estimated cost of services • Proposed idea of smart electrical devices • Cons • No technical details about data transmission mechanism over power line • No discussion of safety and security • Our Opinions • +: Alternative to existing network infrastructure • +: Opportunity for smart devices • -: More trials and testing needed • -: Interference problems? • -: More at the hands of nature: Rain, Snow, .. • -: New medium: Properties of Aluminum wires??? • -: Will it survive the opposition: • ARRL(163,000), FEMA, DERA & many more …
How Stuff Messed Up? Short wave/CB: 5.9MHz – 27.41Mhz Affected FEMA (emergency), ARRL (relay radio)