Misure di compatibilita’
Elettromagnetica
Giuseppe Savoia
Electronic Measurements Group
Agilent Technologies
giuseppe_savoia@agilent.com
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Agenda
 Introduzione alle misure EMI




Terminologia;
Sistema di misura (antenna, LISN, ricevitore, etc.);
Detectors;
Normative europee ed internazionali
 Misure di compatibilita’ elettromagnetica





Misure di emissioni radiate
Misure di emissioni condotte
Misure di immunita’ (EMS)
Setup di misura
Camere anecoiche vs. OATS (Open Area Test Site)
 Soluzioni Agilent





Introduzione al nuovo ricevitore EMI Full Compliance Agilent MXE
Uso degli analizzatori Agilent della Serie-X per misure EMI pre-compliance.
Sorgenti per i test di immunita’
Software applicativo
Soluzioni complete tramite i nostri partners
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What is EMC?
Electromagnetic Compatibility (EMC): The ability of equipment to operate in its
electromagnetic environment without introducing intolerable disturbances into other
devices.
Combination of Interference and Immunity.
Electromagnetic Interference (EMI):
Electromagnetic energy emanating from one device which causes another device to
have degraded performance.
Electromagnetic Immunity (Susceptibility, EMS): Tolerance in the presence
of electromagnetic energy (Performance degradation due to electromagnetic energy).
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Definitions
EMC –
ElectroMagnetic Compatibility
EMI –
ElectroMagnetic
Interference
EMS –
ElectroMagnetic
Susceptibility
(aka Immunity)
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Sources of Electromagnetic Interference
• Natural Sources
Lightning
Sun Spots
• Unintentional emitting products
Power lines
Motors (mixers, hair dryers etc)
Lighting, appliances
• Devices that intentionally emit signals
Most computers
Hand held communication devices
Radar, transceivers, broadcast equipment etc
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EMI measurement system
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Pre-compliance vs. Full compliance measurements
Pre-compliance measurements
Evaluate the conducted and radiated emissions
of a device using correct detectors and
bandwidths before going to a test house for
compliance testing
Full Compliance measurements
Full compliance testing requires a receiver that
meets the requirements of CISPR part 16-1-1 (for
commercial) or MIL-STD-461 (for military), a
qualified open area test site or semi anechoic
chamber and an antenna tower and turntable to
maximize EUT signals.
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Compliance EMI receiver requirements
A CISPR 16-1-1 receiver must have the following functionality in
the range 9 kHz - 18 GHz:
 A normal +/- 2 dB absolute accuracy
 CISPR-specified resolution bandwidths (-6 dB)
 Peak, quasi-peak, EMI average, and RMS average detectors
 Specified input impedance with a nominal value of 50 ohms; deviations
specified as VSWR
 Be able to pass product immunity in a 3 V/m field
 Be able to pass the CISPR pulse test (implies pre-selector below 1 GHz)
 Other specific harmonic and intermodulation requirements
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CISPR Pulse Generator for
Testing the QP response
Purpose of the Schwarzbeck generator
Schwarzbeck Pulse Generator
Establish the reference repetition rate for band A, B, C and D using QPD
The repetition rate can be varied between 1000 Hz and an isolated pulse
The relative equivalent level can be adjusted
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Receiver requirements above 1 GHz
Above 1 GHz regulations require:
1 MHz bandwidth for measurements
No quasi-peak detector
No CISPR pulse test, meaning no additional pre-selector required
 excellent sensitivity
According to current FCC regulations, the maximum test frequency is the
fifth harmonic of the highest clock frequency for an “unintentional radiator”
(for example, computers without wireless connectivity) and the tenth
harmonic for an intentional radiator (such as a cellular phone or wireless
LAN).
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What is an EMI Receiver?
Let’s begin with a spectrum analyzer
Spectrum Analysis
•Display and measure amplitude versus frequency for RF & MW signals
•Separate or demodulate complex signals into their base components (sine waves)
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Overview
Types of Tests Made
Modulation
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Noise
Distortion
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Theory of Operation
Swept Spectrum Analyzer Block Diagram
RF input
attenuator
mixer
IF gain
IF filter
(RBW)
Input
signal
envelope
detector
Log
Amp
Pre-Selector
Or Low Pass
Input Filter
local
oscillator
video
filter
sweep
generator
Crystal
Reference
Oscillator
ADC, Display
& Video
Processing
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RF Pre-selection (RF input filtering)
 Purpose of RF pre-selection
Help to prevent overload by reducing the total energy at the input mixer
The RF preselector tracks the center frequency of the EMI receiver
The bandwidth of the RF preselector is wider that the widest RBW used
Useful in measuring broadband signals
Narrow band
signals
Broadband
signals
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Digital IF Spectrum/Signal Analyzer
Vector data CAN be preserved (mag/phase or I/Q)
Digitizing the IF Signal
Some troublesome operations
and conversions are now
fast, accurate DSP
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Overview
Different Types of Analyzers
FFT Analyzer
A
Swept Analyzer
Parallel filters measured
simultaneously
f1
f2
A
f
Filter 'sweeps' over
range of interest
f1
f2
f
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Specifications
Resolution: RBW Type Determines Sweep Time
8563E Analog RBW
PSA Digital RBW
PSA FFT RBW
280 sec
134 sec
13.5 sec
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Speed Improvements
Nominal speed comparison, PSA example:
Benchmark
PXA
PSA
Speed
improvement
Preset (*RST)
Marker peak search
Local Update
CF Tune and Transfer (4 - 5GHz)
Remote sweep and trace transfer
28 ms
6.5 ms
13 ms
109 ms
18 ms
168 ms
78 ms
17 ms
186 ms
30 ms
6x
12x
1.3x
1.7x
1.67x
Useful comparisons highly specific, many factors
PXA mode switching typically faster than PSA
Where speed is critical, consider modifying measurement routines to
include features such as list sweep
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Modern spectrum analyzer
Resolution BW Selectivity or Shape Factor
3 dB
3 dB BW
60 dB
60 dB
BW
Selectivity
=
60 dB BW
3 dB BW
Determines resolvability of unequal amplitude signals
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Specifications
Resolution: RBW Type and Selectivity
ANALOG FILTER
Typical
Selectivity
Analog 15:1
Digital ≤5:1
DIGITAL FILTER
RES BW 100 Hz
SPAN 3 kHz
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Digital Filter Shape
Better shape factor, biggest selectivity benefit for different signal levels
Equivalent selectivity at a wider, faster-sweeping RBW
digital filters swept an additional 3-4x faster
30 kHz Digital Filter
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CISPR Bandwidth Requirements
Bandwidth
-6dB
-20dB
Measurement Range
CISPR Band
CISPR Bandwidth
9 KHz – 150KHz
A
200 Hz
150 KHz – 30 MHz
B
9 KHz
30 MHz – 1 GHz
C/D
120 KHz
> 1GHz
E
1 MHz
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MIL-STD-461 Bandwidth Requirements
Measurement Range
-6dB Bandwidth
30Hz - 1 KHz
10 Hz
1 KHz -10 KHz
100 Hz
10 KHz - 150 KHz
1 KHz
150 KHz - 30MHz
10 KHz
30 MHz - GHz
100 KHz
> 1GHz
1 MHz
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Detectors: Convert IF Samples to Display Bins or
“Buckets”
Multiple simultaneous detectors
Peak, Neg Peak, Sample
Normal, Average, Neg Peak
Display points or
buckets
Peak
Volts
Sample
Neg Peak
Screen Shot “Detector 3types”
Time
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Detectors
Most radiated and conducted limits are based on quasi-peak
detection mode.
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Peak vs. Quasi-peak vs. Average
V
Peak Detection
Quasi-Peak Detection
Average Detection
time
V
Peak Detection
time
Quasi-Peak Detection
Average Detection
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Peak ≧ QP ≧Average
Peak Detector
• Initially used
• Faster than QP and Average modes
• If all signals fall below the limit, then the product passes and no future
testing is needed.
QP
• For CW signal, Peak = QP
• Much slower by 2 or 3 order magnitude compared to using Peak detector
• Charge rate much faster than discharge rate
– the higher repetition rate of the signal, the higher QP reading
Average
• Radiated emissions measurements above 1 GHz are performed using
average detection
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EMI Receiver Detectors (cont’d)
EMI Average Detection
This is the
response to a pulse
by the average
detector
RMS Average Detection
RMS-average weighting receivers employ a weighting detector that is a
combination of the rms detector (for pulse repetition frequencies above
a corner frequency fc)
and the average detector (for pulse repetition frequencies below the
corner frequency fc), thus achieving a
pulse response curve with the following characteristics: 10 dB/decade
above the corner frequency and 20 dB/decade below the corner
frequency.
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RMS Average detector table
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Modern Spectrum Analyzer Accuracy
Some modern analyzers approach accuracy of power meter + sensor
• Even better for low-level signals, with narrower noise bandwidth and
the benefit of frequency selectivity
Some factors determining uncertainty:
• Input connector (mismatch)
• RF input attenuator
• Mixer and input filter (flatness)
• IF gain/attenuation (reference level)
• RBW filters
• Display scale fidelity
• Calibrator
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Modern Spectrum Analyzer Accuracy Examples
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Line Impedance Stabilization Networks (LISN)
Purpose of a LISN:
1.
Isolates the power mains from the
equipment under test. The power
supplied to the EUT must be as clean as
possible. Any noise on the line will be
coupled to the X-Series signal analyzer
and interpreted as noise generated by
the EUT.
2. Isolates any noise generated by the EUT
from being coupled to the power mains.
Excess noise on the power mains can
cause interference with the proper
operation of other devices on the line.
3. The signals generated by the EUT are
coupled to the X-Series analyzer using a
high-pass filter, which is part of the LISN.
Signals that are in the pass band of the
high-pass filter see a 50-Ω load.
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LISN
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LISN
@ Electrical Network Frequency
@ 150 kHz to 30 MHz
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Transient Limiter
The purpose of the limiter is to protect the input of the EMC analyzer from
large transients when connected to a LISN. Switching EUT power on or off
can cause large spikes generated in the LISN.
Limiter
LISN
DUT
The Agilent 11947A transient limiter incorporates a limiter, high-pass filter,
and an attenuator. It can withstand 10 kW for 10 μsec and has a frequency
range of 9 kHz to 200 MHz. The high-pass filter reduces the line frequencies
coupled to the EMC analyzer.
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Field Strength Unit
Radiated EMI emissions measurements measure the
electric field. The field strength is calibrated in dBμV/m.
Pt = total power radiated from an isotropic radiator
Pd = the power density at a distance from the isotropic radiator
(far field >λ/2π)
Pd
Pt
r2
4
R 120
Pd
E2
R
E2
R
Pt
4
r2
[ohm] Free Space Impedance
r
E
Pt 30
r
[V/m]
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Field Strength and Antenna factors
Radiated EMI emissions tests measure the electric field. The
field strength is calibrated in dBμV/m.
Antenna factors is the ratio of the electric field (V/m) present
at the plane of the antenna versus the voltage out of the
antenna connector.
Log units:
AF(dB/m) = E(dBμV/m) - V(dBμV)
E(dBμV/m) = V(dBμV) + AF(dB/m)
Notes:
Antenna factors are not the same as antenna gain.
dBμV = dBm + 107
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Broadband antenna examples
Double ridged horn antennas
Log Periodic
antenna
Hybrid log periodic
Biconical antenna
Hybrid log periodic
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Close field probe
Measures the magnetic field H strength at the center
of its sense loop. The plane of the probe tip loops
must be perpendicular to the radiating magnetic field
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Test example
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EMC Regulations
An Overview
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Standard Setting Institutions
IEC*
174 Technical
committees and
subcommittees
CISPR
(International Special
Committee on Radio
Interference)
FCC
Federal
Communication
Commission
TC77
(Technical Committee
77) deals with EMC
ANSI
American National
Standards Institute
CENELEC
European standards
organization
*IEC International Electrotechnical Commission
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Frequency Bands
for Conducted and Radiated Emission
Mil-STD Radiated (RE101, RE102)
Mil-STD Conducted (CE106) or Mil-STD Radiated (RE103)
Mil-STD
Mil-STD
Conducted
(CE101, CE102)
CISPR Radiated
Commercial
FCC Radiated
CISPR, FCC
conducted
30Hz 9 kHz 10 MHz 30 MHz
18GHz
To 40 GHz
10 kHz
RE103 may be used as an alternative for CE106 when testing transmitters with their intended antennas.
CE106 is the preferred requirement unless the equipment or subsystem design characteristics preclude its use.
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2011年9月5日星期一
Sun Tong
Who must comply with EMC Directive
Manufacturers of electronic equipment such as:
ITE (information technology equipment)
ISM (industrial, scientific medical)
Broadcast receivers
Household appliances and tools
Luminaries and fluorescent lighting
If a product does not fit into one of the above
categories then it must follow the generic standard
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International emissions regulations (summary)
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Methods for obtaining and placing the CE mark
Self Certify Products or Use an Accredited Test Facility
Pass the tests to the required standard
Sign a “Declaration of Conformity”
Affix the CE mark to the product or package
Alternate method to get a CE mark
Maintain a technical construction file of testing during
development
A technical report is issued by a “competent” EMC test lab
A competent body is authorized on behalf of the government to
carry out the directives
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FCC
Federal Communication Commission
Equipment Type
Broadcast receivers
Household appliances
Fluorescent lights/luminaries
Information technology equipment
Industrial, scientific and medical
FCC Requirement
Part 15
Part 15
Part 15
Part 15
Part 18
Class A, Industrial
Class B, Residential
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CISPR changes…

RMS-Average

Preselector-less testing: enables use of spectrum analyzer for specific
test cases.(no emissions with PRF < 20 Hz)

CISPR 22 to 6 GHz

Time Domain: sometimes required for the automotive market

APD: soon to be required by CISPR11
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European Norms example
EN55014 (CISPR 14)
This standard applies to electric motor-operated and thermal
appliances for household and similar purposes, electric tools
and electric apparatus.
Limit line use depends upon the power rating of the item.
EN55014 distinguishes between household appliances, motors
less than 700W, less than 1000W and greater than 1000W.
Limits for conducted emissions are 150 kHz to 30 MHz, and
limits for radiated emissions are 30 MHz to 300 MHz.
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MIL-STD 461 Testing
MIL-STD 461E
Frequency Ranges
Conducted Emissions
CE101, Power leads, 30 Hz to 10 kHz
-1 limits for submarine DC
-2 limits for submarine 60 Hz
-3 limits for submarine 400 Hz
-4 limits for ASW and Army aircraft
CE102, Power leads, 10 kHz to 10 MHz
CE106, Antenna Terminal 10 kHz to 40 GHz*
Radiated Emissions
RE101, Magnetic field, 30 Hz to 100 kHz
-1 limits for Army applications
-2 limits for Navy applications
RE102, Electric field 10 kHz to 18 GHz
-1 limits for surface ships
-2 limits for submarine
-3 limits for aircraft and space sys
-4 limits for ground applications
RE103, Antenna spurious, 10 kHz to 40 GHz
*Or 20 x highest
internal frequency
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MIL-STD 461 Bandwidths and Measurement Times
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Emissions and Susceptibility Requirements
Summary
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EMC Testing During
Product Life Cycle
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The Need for a Complete EMC Test Strategy
Why Not Just Build the product then test it?
The chances of passing compliance testing is less than 10%
The cost of failure:
Market window lost (Competitor beats you to market)
Additional engineering time
Cost of fixes to pass emissions
Cost of retesting
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Production
Prototype
Breadboard/Design
EMI problem costs
The Cost of EMI solutions as the
project progresses
Project development time line
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Compliance Testing
for Emissions
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Confidentiality Label
57
The compliance measurement process
Before making measurements on your product, some
preliminary questions must be answered.
1. Where will the product be sold (for example, Europe, United
States, Japan)?
2. What is the classification of the product?
a.
b.
c.
d.
Information technology equipment (ITE)
Industrial, scientific or medical equipment (ISM)
Automotive or communication
Generic (equipment not found in other standards)
3. Where will the product be used (for example home,
commercial, light industry or heavy industry)?
With the answers to these questions, you can determine
which standard your product must be tested against.
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General Process for Making EMI Measurements

Determine the country or countries in which the product
will be sold which in turn identifies the regulator agency.

Select the limit lines to be tested to (conducted/radiated).

Select the band to be used.

Correct for transducer loses and amplifiers gains.

Identify signals above the limit that must be evaluated.

Zoom in on failed signal and perform quasi-peak or
average measurements.
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Conducted Emissions Measurements
1. Connect DUT to the test system
2. Set the proper frequency range
3. Load limit lines and correction factors for LISN and limiter
4. View the ambient emissions with DUT OFF
5. Switch on the DUT and find signals above limits by using peak detector
6. Measure all signals above limits with quasi-peak and average detectors
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The challenge of measuring radiated emissions
Radiated Emissions are difficult to
measure because of multiple
dimensions (five) and the use of
quasi-peak detection below 1GHz
5 -Time
1 - Azimuth
2 - Antenna Height
3 - Field Strength
1500.260MHz
218.120MHz
4 - Frequency
41.2563MHz
Examples of Test Facilities
Open Area Test Site (OATS)
Useful in low ambient signal
environments
GHz Transverse Electro
Magnetic Cell (GTEM Cell)
Used for smaller
devices. Can be used for
immunity and emissions.
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Open Area Test Site (OATS)
EUTs are measured in an open area test site (OATS) or anechoic chamber.
ANSI C63.4 and CISPR 16-1-1 specify the requirements for an OATS, including:
 Preferred measurement distances
of 3, 10, and 30 meters
 Antenna positioning at 1 to 4 meter
Heights
 An area called the “CISPR ellipse”
of major diameter 2X and minor
diameter √3 • X, where X is the
measurement distance; the ellipse
must be free of any reflecting objects
 A metal ground plane for the measurement area
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GTEM Cell details
RF output for
emissions testing
or
RF input for
immunity testing
DUT Area
Septum
terminated
in 50 ohms
RF
absorbers
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Test Facilities (cont’d)
10 Meter Semi Anechoic* Chamber
This chamber uses 2 antenna
towers, one for vertical and
one for horizontal polarization.
Uses a ground plan.
Reverberation Chamber
Uses a mode stirring tuner to
generate a uniform field (no
absorption material on the walls)
*Anechoic material are made
of carbon impregnated
rubberized cones or ferrite
tiles or both
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Radiated Emissions Measurements
1. Connect the antenna
to the EMI receiver and
separate the antenna from
the DUT as specified by the
regulation requirements
2. Set the proper frequency
range and bandwidth
3. Load limit lines and
correction factors for
antenna and cable.
4. With DUT OFF, measure the ambient emissions and store them
5. Switch on the DUT and find signals above limits by using peak detector (only those
not present during the ambient scan). Rotate the DUT to maximize the emissions.
6. Measure all signals above limits with quasi-peak and average detectors
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1. Select the measurement range
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2. Load Corrections factors
Amplitude at
point circled
Amplitude
referenced to
blue line
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3. Load Limit line
Circle indicates
the position of
the amplitude
frequency pair
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4. Scan for signals above the limits with peak detector
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5. Quasi-peak and average measurements
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Once EMC testing becomes part of the product
strategy (THEN WHAT)
Continue to use test
houses at $$$$ per hour
Build your own facility for M$ +
OR
Purchase and setup a
precompliance system
X-Series signal analyzer
with N6141A /EMC app.
LISN
Antennas and tripod
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Precompliance testing
Approach Full Compliance Testing Accuracy…
At a fraction of the cost of full
compliance testing
Minimum Precompliance test system Pricing
Product
Price
CXA Signal Analyzer to 7 GHz
16.3k USD
W6141A EMC application
4.1k USD
LISN
2.4k USD
Biconical Antenna
~5k USD
Log Periodic Antenna
~5k USD
Antenna Tripod
~0.5k USD
Total Price
~33.3k USD
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Automation in Precompliance Measurements
Reasons for Automation
-Supplement skill and knowledge of the tester
-Measurements repeatability
-Results are presented in a common format
-Reduce test time by automating setups
Types of Automation
-Internally executed application such as N6141A
-PC based applications
Software Available
-Techcelerant, TILE from ETS Lindgren, TDK RF Solutions, Radimation
from DARE
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Precompliance Conducted Emissions Setup
To Mains
X-Series Signal
Analyzer
LISN
DUT
With N6141A
EMC App
DUT power cord*
Transient
Limiter
*Keep the power cord short to avoid
becoming an antenna
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Precompliance Radiated Emissions Setup
Perform testing in both the
horizontal and vertical position
3 or 10 Meter distance
DUT
X-Series Signal Analyzer
with N6141A EMC App
Ground Plane
The goal is to find and record the maximum emissions from the DUT by rotating the
turn table, changing the polarity and the height of the antenna.
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Troubleshooting
Use the close-field probe to locate the sources of the radiated signals
exceeding the limit lines
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Immunity test setup
Radiated Immunity
30 MHz – 18 GHz
Amplifiers
HF-Switch
Conducted Immunity
100 kHz – 1 GHz
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Agilent Solutions
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What is a CISPR 16-1-1 Compliant Receiver
CISPR is a subcommittee of the IEC
CISPR 16-1-1 is the document that defines the
functionality of an EMI receiver
Detectors
Frequency
response
N9038A MXE EMI receiver is CISPR 16-1-1 2010 Compliant
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EMI Receiver Requirements for Compliance
Testing of Conducted and Radiated Emissions
N9038A MXE
Compliant
receiver
 CISPR 16-1-1 2010
-200 Hz, 9 kHz, 120 kHz (6 dB) and 1 MHz (imp) bandwidths
-Peak, Quasi-peak, EMI average, RMS average detectors
-RF Pre-selection to meet CISPR pulse generator response
-VSWR, 0dB and ≥ 10dB input attenuation
-Amplitude Accuracy
 MIL-STD 461
-Peak detection only
-MIL STD BWs (10 Hz, 100 Hz, 1 kHz, 10 kHz, 100 kHz, 1 MHz)
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What is the MXE EMI Receiver?
The Agilent MXE is more than a CISPR 16-1-1 compliant EMI
receiver
It is also an X-Series signal analyzer that can run a variety of
measurement applications
The MXE can evolve as technology changes
X-Series
signal
analyzer
CISPR 16
compliant
EMI receiver
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N9038A MXE EMI Receiver
in 30 seconds
Compliant RF
Preselection 20 Hz
to 3.6 GHz in both
EMI Receiver
Mode and SA
Mode on
CISPR 16-1-1 2010
Compliant EMI Receiver
Both Inputs
uWave
preselection above
3.6 GHz
20 Hz to 1 GHz for
Conducted Emissions
(built-in limiter)
Agilent Exclusive Noise
Floor Extension
20 Hz to 26.5
GHz for
Radiated
Emissions
LB
20 Hz -1GHz
CFB
INB
DDS
RFB
Noise Source
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Agilent X-Series Signal Analyzers
 Multiple instruments in one box:








Swept spectrum analyzer;
FFT analyzer;
RF and Baseband Vector Signal analyzer;
Noise Figure analyzer.
Fastest signal analysis measurements
Broadest set of applications and demodulation capabilities
Upgradeable HW
Most advanced user interface & world-class connectivity
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“All Digital IF” Advantages
RF Section
ADC
FFT
IF/BB Section
on ASIC
 Flexibility:
 RBW filtering in 10% steps
 Filters with better selectivity
 Multiple operation modes (Swept, FFT, VSA, NFA)
 Accuracy:
 Log conversion practically ideal
 No drift errors; increased repeatability
 Speed:
 When Swept mode is slow, go FFT
Techniques for Reducing DANL, Improving Dynamic
Range
Reduce attenuation
Add preamp
Reduce RBW
Add external filtering
Better/shorter cables, connectors
Move analyzer closer
Time averaging (where possible, not measurement avg.)
Measurement processing (take advantage of Moore’s Law)
• Noise power subtraction/noise correction/NNC
• Noise floor extension (NFE) leverages deep knowledge of
analyzer/circuit behavior
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CW Signal Measured Near Analyzer Noise Floor
Example: No noise subtraction or near noise correction
Apparent
Signal
Displayed
S/N
Actual S/N
CW Signal
Ampl & Freq
Axes Expanded
This is
fundamental, and
often missed
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Noise Floor Subtraction
PobsS+N = PobsN + PS
PS = PobsS+N − PobsN
Analyzer noise adds incoherently to any signal to be measured
Power calculations are performed on a linear power scale
(watts, not dBm) and results typically are shown in dBm
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Noise Subtraction, “Noise Floor Extension”
New technique “NFE” improves D.A.N.L.
analyzer noise power calculated/subtracted real time
“No” error
3 dB error
without NFE
Improved noise floor
or displayed average
noise level
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Analyzer Noise Floor with NFE
Source still off, green trace shows analyzer noise level with NFE
Other measurement conditions unchanged
Note high variance result from subtraction of small, noisy numbers
Analyzer DANL now far enough below source for minimal
(0.2 - 0.4 dB) error
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EMC Features standard in all X-Series Spectrum
analyzers
• Limit Lines (2000 pts)
• Amplitude correction (2000 pts)
• 40001 sweep points
EMI Roadmap
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9/29/2011
Option EMC in X-Series spectrum analyzer
 CISPR 16-1-1 detectors
(to latest spec)
 Quasi Peak
 EMI Average (“CISPR-AVG”)
 RMS Average (“CISPR-RMS”)
 EMI Bandwidths (CISPR & MIL STD)
 EMI Presets
 Tune & Listen
 Measure at Marker
 EMI Peak, EMI Average, and
Quasi Peak measurements
displayed together
Page 94
W/N6141A EMC measurement application
 Full Featured Pre-compliance Application
 Available in all X-Series models
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Page 95
Corrections factors edit display
Amplitude at
point circled
Amplitude
referenced to
blue line
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Page 96
Limit line edit display
Circle indicates
the position of
the amplitude
frequency pair
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Page 97
Log Display
Auto-detect peaks
Peak List
Page 98
Realtime
Meters
with any 3
Simultaneous
Detectors
Limit Delta
N6141A measurement: Frequency Scan with Log Display
Meters tune
to selected
signal
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N6141A measurement: Strip Chart
• Time record
of zero span
data scrolls
to left
• Up to three
different
detectors
• Can be used
to make
“click”
measurements
Patent
Applied
For
Click measurements are made on home appliances
EMI Roadmap
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9/29/2011
Option EDP (Enhanced Display Package) for the SA
• Spectrogram
• Trace Zoom
• Zone Span
Group/Presentation
Title
EMC seminar
Agilent Restricted
Page 101
N6141A EMI Measurement Application
PXA
MXA
Pre-compliance
EXA
CXA
Compliance
Agilent MXE N9038A
EMC seminar
Agilent products for Immunity test (EMS)
Signal
generator
9 kHz – 3 GHz, AM, FM, Phase, Pulse IQ Modulator,
40 MHz Mod.-BW
Signal
generator
N5182A, N5182A, N5183A
100 kHz- 1,3, 6, 20, 40 GHz, AM, FM, Phase, Pulse,
optional vector, 120 MHz Mod.-BW, step , sweep,
USB-Power meter included
Power meter/
Power sensors
E441x, E191x, N8262, U200x
100 kHz – 40 GHz
single channel, dual channel, USB, peak, envelope,
pulse
Accessories
Directional Couplers, cables, Adapters, Switches etc.
EMC seminar
Solution partners for EMC
Complete solution:
1. Automation software
2. Chambers
3. GTEM
4. Antennas
5. Power amplifiers
6. Accessories
EMC seminar
Page 104
Per ulteriori informazioni su prodotti ed applicazioni EMI/EMC
visitare il sito
http://www.agilent.com/find/EMC
Contatti:
Agilent Technologies Italia
Roberto Sacchi
Application Engineer
E-mail: roberto_sacchi@agilent.com
Giuseppe Savoia
Signal Analysis and Generation Sales Specialist
E-mail: giuseppe_savoia@agilent.com
Agilent Contact Center
E-mail: contactcenter_italy@agilent.com
Tel:
02 9260 8484
EMC seminar