Broadband over Power Line (BPL) Test
Procedures and Equipment
Authorization
Andy Leimer
Equipment Authorization BranchFederal Communications Commission
Office of Engineering and Technology
Laboratory Division

BPL and Carrier Current System (CCS)
Existing Rule Review

BPL devices are “carrier current systems”[15.3(f)] – BPL is a Subset of CCS

Part 15 interference requirements– Must not cause harmful interference - Anyemission, radiation or induction that
endangers the functioning of a radionavigation service or of other safety
services or seriously degrades, obstructs orrepeatedly interrupts a radiocommunicationsservice operating in accordance with thisChapter. [15.3(m)]– Must accept interference from other devices
February 2005

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BPL and Carrier Current System (CCS)
Existing Rule Review (Con’t)
Emission limits– AC-Line Conducted limits [15.107]• Devices operating < 30 MHz:
1000 uV in 535 –1705 MHz• Devices operating > 30 MHz:
Same as digital
device limits (150 kHz – 30 MHz)– Radiated limits• < 30 MHz Intentional radiator limits [15.209]– 1.705-30 MHz: 30 uV/m at 30 m)• > 30 MHz Unintentional radiator limits [15.109]
Class A and Class B Limits
Field strength measurements are “in situ”– Three representative installations

February 2005

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Access BPL Scope
In-house BPL– No change to existing rules– New measurement guidelines

Access BPL
Definition: A carrier current system that transmits radio
frequency energy by conduction over electric powerlines owned, operated, or controlled by an electric
service provider. The electric power lines may be aerial(overhead) or undergroundFebruary 2005

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Access BPL Scope (Con’t)
Existing rules remain in place– Conducted limits do not apply toAccess BPL– Class B radiated limits apply to lowvoltage “drop” lines
New rules added to support interference
mitigation
New measurement guidelines for BPLand CCSFebruary 2005

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BPL Report and Order (R&O)
R&O (FCC 04-245)– Rules published in the Federal Register
January 7,2005– New Subpart G

http://hraunfoss.fcc.gov/edocs_public/attachmatch/FCC-04-245A1.pdf
Transition Provisions– New equipment must comply 18 months after publication in
the Federal Register– Existing equipment may operate for duration of useful life if
there are no reported instances of harmful interference

Erratum
DOC-254180A1.doc
February 2005

TCB Workshop

6New Access BPL Rules
Certification required for Access BPL
Access BPL must include adaptive
interference mitigation capabilities to avoid
local and site-specific interference– Exclude or “notch” any specific frequency or band
– Remotely shut off any BPL device

Excluded Bands– 12 Aeronautical frequencies

Exclusion zones – frequencies prohibited
based on distance– US Coast Guard or maritime coast stations– Radio astronomyFebruary 2005

TCB Workshop

7New Access BPL Rules (Con’t)
Establishes “consultative requirements” for
BPL with public safety, and certain sensitive
federal and aeronautical stations
Establishes a “good faith” process to ensure
that– Access BPL systems do not cause interference– Any BPL restrictions by licensees are only thosenecessary to avoid interference

Industry to establish a public accessible
database deployment information
Interference complaint procedures
February 2005

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BPL General Information
Access BPL - EUT defined as device (notsystem) requiring Certification– May include the electronic equipment enclosure,coupling device, and medium voltage lines that areinjected (Phase and neutral if both are injected),
including the power line(s) to which the device
couples– Pole ground wires not considered to be part ofEUT

All BPL system components require separate
certification.
Currently, TCBs cannot authorize Access BPL
devices
February 2005

TCB Workshop

9Operational Description
Describe device function – injectors, extractors,
repeaters, boosters, concentrators, couplers, etc.
Describe BPL coupling of the medium voltage line (ifapplicable) distribution to customer premises(coupled around low voltage transformer, directly
through the low voltage transformer, IEEE 802.11,other)Frequency range(s), BW, Modulation, variable power
setting, notch filtering, duty factor, data rates, etc.
Configuration – setup and control, signal routing, how
is device used in a BPL system
Notch Capabilities – frequencies, 20dB BW, control,
cold power-up defaults
February 2005

TCB Workshop

10Test Site Selection
In-Situ Testing (Part 15.31(d))– three typical
overhead line installations and three typicalunderground line installations.
Overhead Line - unobstructed access to:– Pole containing electronic enclosure and couplers– Medium voltage lines for distance of 1 wavelength (midband) at a minimum 10m horizontal distance from the power
line

Underground Line – select transformer or BPL
equipment box away from cable TV and telephone
utility connection boxes– Power company layout map helpful to locate the location of
the underground wiring
February 2005

TCB Workshop

11Test Site Selection (Con’t.)
Avoid the following if possible:– Splits in overhead lines– Risers that connect to underground lines

Noisy lines can result in inconclusive QP
measurements

February 2005

TCB Workshop

12Determining Maximum Emissions
to be Tested
Peak emissions across the band
Power average (100 sweeps) reduces the effects of ambients andnoise - recommended
9 kHz RBW < 30 MHz and 100 kHz RBW > 30 MHz
Antenna selection– Active Loop < 30 MHz• Increases measurement S/N ratio• Greater risk of overload due to AM broadcast stations• Greater frequency range without switch setting– Passive Loop < 30 MHz• Less risk of overload• Can use external pre-selection filtering directly on theantenna
February 2005

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Determining Maximum Emissions
to be Tested (Con’t.)
Bicon > 30 MHz
External Amplifiers – engineering judgment
Low-pass and high-pass filters recommended to reduce AM/FM &TV broadcast band effects

February 2005

TCB Workshop

14Radiated Emissions Testing
Significant medium voltage line emissions seen as a
– Measure at a 10m horizontal distance from the line, if

Ensure that maximum or near-maximum RF injection– Use maximum data rate available. This can be configured by– Data communications must result in at least 20 Hz minimum

February 2005

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Radiated Emissions Testing (Con’t.)
Test at 0, 1/4,1/2, 3/4, and 1 wavelength down the– Slant range distance up to 30m• Overhead line distance correction based on Slant Range– Recommended minimum horizontal distance from pole or– Loop antennas: 1m antenna height, maximized from parallel– Bicon antennas: Scan from 1 to 4m antenna height, H & V• Alternative procedure – measure at 1m antenna height

February 2005

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Slant Range Distance
Distance Specified in Rule (e.g., 30 m for <30 MHz)14m

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• Loop antenna axis is parallel to ground: test withaxis both parallel & perpendicular to power line
• E-field measurements should be made for verticalpolarization and polarization parallel to power line

• Preferred Measurement Distance: 10 meters horizontal• Extrapolate to specified distance using slant range - overhead lines• 40 log(range) below 30 MHz• 20 log(range) above 30 MHz
February 2005

TCB Workshop

17Radiated Emissions Testing (Con’t.)
Antenna orientation and position forunderground installations:– 16 radials– Loop antennas: 1m antenna height, maximized
from parallel to line to +/-90 degrees(perpendicular to line)– Bicon antennas: 1 to 4m antenna height, H & V
polarization

Maximize the signals in accordance to ANSII
C63.4 – explain the test procedure in detailand report the worst case emissions
February 2005

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Radiated Emissions Testing (Con’t.)
QP measurements:– Maximize the BPL data rate for uplink anddownlink– Maximum six discrete frequencies across theband (Recommended for non-digitizing
analyzers). Zero span measurements
recommended for older analyzers.
– Sweep the band that includes the maximumemissions (Note: maximum 50 kHz sweeps for QP
measurements < 30 kHz (9kHz RBW))
The measurement procedures for medium voltage
lines and low voltage lines are identical. Medium andlow voltage lines (if applicable) must both be tested.
February 2005

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Access BPL Equipment
Authorization - Additional Items
FCC ID Label– Font size TBD

User’s Manual– Device not marketed to public– An Installation Manual is required– Specify settings and control for operation incompliance with the Rules

Notch capability– Test procedure not addressed in R&O– Manufacturer’s compliance statement required
February 2005

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In-House BPL Modem
Equipment Authorization
CCS requiring Verification• In-situ testing - three test sites• Test at 3 positions along overhead power service
line to house

Class B Computer Peripheral (JPB)• DoC or Certification (Section 15.101)• Table top testing – radiated and conductedemissionsFebruary 2005

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Thanks!
Thanks!
February 2005

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