BPL Interference: Fact or Fiction

1
BPL Interference Fact or Fiction?

• Barry Malowanchuk P.Eng.
• Sr. Communications Engineer
• Manitoba Hydro
• 2005 UTC Region 5 Conference
• April 20, 2005
• Fergus Falls, Minnesota

2
BPL Interference Fact or Fiction?

• What is BPL Why is It Significant?
• Technical Specifications?
• Is There Interference or Not?
• Will Emission Limits Prevent it?
• Is BPL in Your Future?

3
What is BroadBand Over PowerLine?

• A System that Enables Delivery of High Speed
  BroadBand Data Over Medium and Low Voltage
  Power Lines
• There are at Least Four (4) Distinct
  Manufacturers Offering Ways to Do This ..
• ..and So Far There is No Industry Standard

4
Basis of European Technology
5
Basis of North American Technology
6
BPL 3-Architectural Configurations
7
Amperion (NA)Architecture
Falcon/Griffin overhead PLC
Substation
Transformer
Internet
FIBRE or COPPER
Connection to Internet
Transformer
Lynx underground PLC
8
Amperion Connect Products
Griffin
Lynx
Overhead Wire Mount
Underground
Overhead Pole Mount
9
Amperion Unit Functional Descriptions

• Injector Receives Wireless, Launches PLC signal
• Repeater Receives PLC signal, Transmits PLC to
  next
• Repeater,
  Wireless to/from Users
• Extractor Receives PLC signal, Wireless to/from
  Users
• Very-low latency
• Repeatable over extended distances
• Single segments up to 2500 ft on Good Lines
• Up to 24 Mbps throughput

10
Amperion Deployment Pictures
Antenna on Street Light
Couplers in Transformer
Lynx Injector
Mast Antenna
Griffin
11
Why Bother With BPL?

• 75 of Canadians Have Internet Access
• 48 of Canadian Home Users have a BroadBand
  Connection (21 in U.S.A., and 5 in Europe
• Thus 30 of ALL Canadians Have a BroadBand Home
  Internet Connection
• Why Not More?......
• Large Areas of Population are Un-Served

12
Why Bother With BPL?

• The Power Grid has Universal Coverage
• Provides 3rd Home Service Alternative to DSL and
  Cable
• Potentially Lower Cost Service
• Opportunity to Serve Unserved Areas
• Once installed BPL provides a Network for Utility
  Services

13
What Are Utility Services?

• Customer Interface
• Automatic Meter Reading
• Service Connect/ Disconnect
• Intelligent Home Services
• Distribution Automation
• Operational Diagnostic Data
• Mobile Data to Work Force

14
BPL Technical Properties

• Many/ Most BPL Modems Use Orthogonal Frequency
  Domain Modulation (OFDM)
• Typical BPL OFDM Modem Characteristics
• 45 Mbps using 1,280 Distinct Carriers
• Adaptive Bit Rate per Carrier Depending on
  Channel S/N Conditions
• Spectrum Usable from 1.7 to gt80 MHz
• Only 10 MHz of Bandwidth used per Modem

15
Typical OFDM Modem Spectra
16
BPL Technical Properties Contd

• Transmit and Receive Spectra Will be Shared or
  Split in an OFDM Modem
• Modems at Repeater Stations Must use Time
  Division Multiplexing or Frequency Changes to
  Avoid Interference
• Thus the Spectrum Use may be Double that of a
  Single Modem
• Next Generation Devices _at_ 200 Mbps Available in
  2005 - No Details

17
BPL Radio Interference Problem?

• BPL Signal is Digital...Broadband Noise
• Can Travel by Conduction /or Radiation
• Power Wires on MV Lines are Spaced by a
  Significant Distance..Radiation
• Power Wires on LV Lines are Twisted and often
  Buried Coaxial.Shielded?
• Radio Interference is Very Controversial and the
  Subject of Much Lobbying Some Field Testing

18
Is There Interference or Not?

• Thus the Fear of Interference is Unfounded,
  Despite Opponents Rhetoric that BPL is a
  Pandoras Box of Unprecedented Proportions.
• Brett Kilbourne UTC Fall 2003

19
Is There Interference or Not?

• The Commission proposes Rules requiring BPL
  devices to employ adaptive interference
  mitigation techniques to prevent harmful
  interference to existing users, such as public
  safety and amateur radio operators.
• FCC News Release, February 12, 2004

20
Is There Interference or Not?

• The Commissions Overarching Objective Create a
  Regulatory Environment Hospitable to BPL without
  Degrading Existing Services
• Clearly the Commission Believes the Potential for
  Interference Exists

21
Will Emission Limits Prevent it?

• The Consensus is that the Existing Part 15
  rules Do Adequately Protect licensees from BPL
  operations.
• Brett Kilbourne UTC Fall 2003

22
Will Emission Limits Prevent it?

• These Guidelines will ensure that Emission
  Measurements for these systems are made in a
  Consistent Manner.
• It does Not Propose Any Changes to Existing
  applicable Emission Limits.
• FCC News Release, February 12, 2004

23
Will Emission Limits Prevent it?

• However the Commission Proposed Techniques to
  Mitigate Interference to existing users
  ..including
• Cessation of Operations altogether,
• Dynamic Reduction of Transmit Power,
• And/or Avoid operating on Specific Frequencies to
  Prevent Harmful Interference
• FCC News Release, February 12, 2004

24
Will Emission Limits Prevent it?

• Need to Look at RF Environment as a Whole
• Existing Interference Environment/ Background
  Noise
• Urban Rural are Dramatically Different
• Physical Proximity of BPL to Users
• Nature of BPL Implementation
• Set Appropriate Interference Temperature

25
Example of Existing Interference Environment/
Background Noise

26
Will Emission Limits Prevent it?

• The Consensus is that Emission Limits Greatly
  Exceed (gt20 dB) the User Background Noise levels
• This Means that Operation Within Limits Can
  Cause Severe Interference
• How Can That Be?

27
Will Emission Limits Prevent it?

• Emission Limits Provide a Convenient Measure to
  Evaluate Equipment Performance
• Emission Limits Were Developed for an Analog
  World..Before Broadband !
• When Emissions were a Narrow Spike of Energy on
  One (1) or 2 Frequencies
• Not a WALL of Closely Spaced Spikes that FILL the
  Spectrum

28
BPL Interference Mitigation Techniques

• Cessation of Operations Altogether!
• Dynamic Reduction of Transmit Power?
• Practical but Undesirable
• Avoid Operating on Specific Frequencies to
  Prevent Harmful Interference
• Practical with OFDM Frequency Hopping Modems
• Potentially Limiting of Data Bandwidth Capability
• Careful Planning of Spectrum Use Will Be
  Required

29
BPL Interference Mitigation Techniques

• Avoid Operating on Specific Frequencies to
  Prevent Harmful Interference
• Successfully Demonstrated by HomePlug in Europe
  USA
• Recently Demonstrated by a BPL OFDM Modem User/
  Manufacturer
• The Technology Can/ Does Work Around Interference
  !

30
BPL Mitigation Techniques Selective Avoidance
31
BPL Mitigation Techniques

• Newer Technology is Much Better than Even 3 years
  Ago , When Many Foreign Trials Were Conducted in
  Netherlands, Finland, Austria Japan.
• BPL Receivers Now Operate With Much Lower
  Signal Levels
• Able to Reduce Transmitter Powers
• Interference Should Be Manageable !

32
Co-Operation Between Combatants?

• NTIA Issues April 27/04 Phase 1 Report
• Reports Interference Potential Well Removed From
  Lines Because of Line Discontinuities
• Interference to Commercial Aircraft
• Need to Refine Measurement Procedures
• A Number of Technical Recommendations Including
  Balanced Injection Filters/ Traps
• Phase II Report to Look at Interference Via
  Ionospheric Propagation of BPL Signals

33
Co-Operation Between Combatants?

• Obviously Much Lobbying by UTC, PLCA,
  Manufacturers on One Side
• National Association for Amateur Radio (ARRL)
  with 163,000 Members Lobbying on the Other Side
• Clearly the FCC has Recognized the Potential for
  Interference and Wants to Find a Compromise

34
Co-Operation Between Combatants?

• The Technology Exists to Mitigate Interference
• There has Already Been SOME Good Cooperation
  between Utilities, Manufacturers and the Present
  Spectrum Users
• Clearly the Time has Come for All Parties to Work
  Together Before Utilities Deploy Systems !

35
Is BPL in Your Future?

• Absolutely HUGE Interest by US Canadian Federal
  Local Governments
• Strong Interest by Utility Commercial
  Telecommunications Distribution
• Strong Desire for Distribution Automation
  Communications

36
Is BPL in Your Future?

• There are Many Technology Trials
• There are Very Few Commercial Deployments
• The Recent Talk Suggests that Business Case Must
  Include Utility Applications
• Coming to Your Utility in a Small Town Near You ?

37
BPL Interference Fact or Fiction?

• What is BPL Why is It Significant?
• Technical Specifications?
• Is There Interference or Not?
• Will Emission Limits Prevent it?
• Is BPL in Your Future?
• Questions?