BPL

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BPL

• The RFI Challenge
• Gary Box, MSEE
• N0JCG_at_ARRL.NET

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FCC in their Notice of Proposed Rulemaking on BPL

• Operators would have a strong incentive to
  exercise the utmost caution in installing their
  systems to avoid harmful interference and ensure
  uninterrupted service to their customers.

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SYSTEM DIAGRAM
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BPL Interference Paths
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BPL INTERFERENCE PATHS

• Near field component
• Less than 10 wavelength distance
• Can only be reduced by shielding
• Radiated component
• More than 10 wavelength distance
• Can be reduced by good transmission line
  technique (but power distribution lines are NOT
  good transmission lines).

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RADIATED FIELD
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Interference From BPL

• Path gain between BPL device and victim receiver
  can vary over several orders of magnitude.
• Difficult to devise one size fits all solutions
  involving only the BPL components
• Installation of each device would have to be
  custom engineered
• Field service may have to re-engineer every time
  there is an interference complaint.

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INTERFERENCE TO BPL

• Carrier at AGC saturation
• BPL bit rate begins to drop.
• High level carrier will clamp the receiver and
  may damage it
• Only way around it is electrical filter on BPL
  input (but this degrades the BPL bandwidth
  throughput)

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HF USERS

• All HF communication makes use of the most
  important property of the frequencies between
  2MHz and 30MHz the ability to establish and
  maintain communications over great distances
  without any intervening man made infrastructure
  whatsoever.

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HF USERS
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Broadcast
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Aviation
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Amateur Radio Service
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Marine and Land Mobile
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HAP CHART
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The BPL Spectrum
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The Spectrum with BPL
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NTIA REPORT

• Registration
• Frequency agility
• Power reduction
• Avoidance of local frequencies

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NTIA REPORT

• Operation with minimum power
• Differential mode injection
• Filters and terminations to extinguish the BPL
  signal
• Careful choice of frequencies to decrease
  radiation.

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FCC Report Order 04-245

• Excluded frequency bands exclusion zones
• Ability to avoid using any specific frequency and
  remotely adjust or shut down any unit
• Consultation requirements with public safety
  agencies, federal government sensitive stations,
  and aeronautical stations

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FCC Report Order 04-245

• Publicly available Access BPL notification
  database
• Changes the equipment authorization for Access
  BPL systems from verification to certification
• Improves measurement procedures for all equipment
  that use RF energy to communicate over power
  lines.

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Excluded Frequency Bands

• 2,850 3,025 kHz
• 3,400 3,500 kHz
• 4,650 4,700 kHz
• 5,450 5,680 kHz
• 6,525 6,685 kHz
• 8,815 8,965 kHz
• 10,005 10,100 kHz
• 11,275 11,400 kHz
• 13,260 13,360 kHz
• 17,900 17,970 kHz
• 21,924 22,000 kHz
• 74.8 75.2 MHz

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Excluded Frequency Bands
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Ability to avoid using any specific frequency and
remotely adjust or shut down any unit

• Devices must be independently adjustable
• Devices must maintain adjustment

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Consultation requirements with public safety
agencies, federal government sensitive stations,
and aeronautical stations

• At least 30 days before operation
• System must then be designed to avoid
  interference on locally used bands

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Publicly available Access BPL Notification
Database

• Name of BPL provider
• Frequencies of BPL operation
• Postal zip codes served by specific BPL operation
• Manufacturer, FCC ID, Trade Name and Model Number
  of BPL equipment
• Contact phone number and e-mail
• Proposed or actual date of operation

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The Complaint Process

• Licensed user informs BPL contact
• Plaintiff and BPL operator agree on schedule for
  resolution
• For public safety users, response of BPL operator
  must be within 24 hours. BPL operations must
  cease if not resolved in 24 hours.

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FCC Certification required for Access BPL systems

• Performance of BPL equipment must be certified by
  independent lab or the FCC
• Ability to exclude frequencies, performance of
  notching, remote adjust and shutdown, will all be
  tested.

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Measurement Procedures for BPL Equipment

• FCC recommends that the BPL operator perform
  initial installation and periodic testing of
  Access BPL systems on his power lines.
• The BPL operator is responsible to ensure that
  the system maintains compliance with Part 15
  emission limits.
• Impact on utility? Skills? Resources?

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TRIAL RESULTS Raleigh, NC

• TOOLS Power reduction, some ability to mask out
  frequencies and the ability to shift the BPL
  spectrum
• PROCESS Mobile ham radio transceiver and antenna
  system to measure progress. Trial and error over
  a period of 5 months

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TRIAL RESULTS Raleigh, NC

• RESULTS Interference reduced most of the eight
  high frequency ham bands, although not all.
  Progress Energy announced they were terminating
  the test and concluded that they were not going
  to pursue further BPL deployment at this time.
• NOT DONE No evaluation of interference to the
  shortwave broadcast, aeronautical, marine, or
  NTIA frequencies.

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TRIAL RESULTS Cedar Rapids, IA

• TOOLS Power reduction, some ability to mask out
  frequencies and the ability to shift the BPL
  spectrum
• PROCESS Fixed base transceiver and antenna
  system. Trial and error over a period of 2 months

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TRIAL RESULTS Cedar Rapids, IA

• RESULTS Some improvement was achieved, but not
  complete success. Allient energy terminated the
  Cedar Rapids BPL test earlier than they had
  expected to and issued a notice that they would
  not be pursuing BPL at this time.
• NOT DONE No evaluation of interference to the
  shortwave broadcast, aeronautical, marine, or
  NTIA frequencies.

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TRIAL RESULTS Penn Yan, NY

• TOOLS Power reduction, some ability to mask out
  frequencies and the ability to shift the BPL
  spectrum
• PROCESS Little involvement with local Amateurs.
  Trial and error over a period of 3 months

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TRIAL RESULTS Penn Yan, NY

• RESULTS Village of Penn Yan decided that BPL was
  not commercially viable and terminated operation
  of the BPL system. Vendor has since begun
  deploying a wireless network in Penn Yan.
• NOT DONE No evaluation of interference to the
  shortwave broadcast, aeronautical, marine, or
  NTIA frequencies.

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BPL INTERFERENCENear Future

• Vendors will re-engineer to meet new FCC rules
• Certification testing performed
• Test deployments with new equipment
• More thorough evaluation of performance
• In 6 Months BPL database goes live
• In 18 Months all BPL equipment must be certified.
  

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BPL Interference compared to other Broadband
access technologies

• DSL Tightly-coupled differential transmission
  line minimizes radiation.
• Coax fully shielded transmission line minimizes
  radiation,
• Fiber Completely optical, ZERO radiation
• Wireless uses dedicated microwave frequencies
  not shared with other licensed servicesinterferen
  ce minimal

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Future of BPL

• Limited bandwidth, further constrained by
  chopping out slices due to interference
• The spectrum is what it is, cant grow more
  spectrum. Power lines will not sustain microwave
  transmission, so BPL has finite, limited BW
• Cable, Wireless and particularly Fiber have far
  greater bandwidth growth opportunity, without
  interference to other licensed services.
• Interference both IN and OUT will lead to a lot
  of unpredictable service calls

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BPLs RFI ChallengeRemains

• Operators would have a strong incentive to
  exercise the utmost caution in installing their
  systems to avoid harmful interference and ensure
  uninterrupted service to their customers.

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Any questions?