RefRad Model 3000 System Check of Frequency Selective EMC/EMF -

FOR-EMC: RE-System Check with RefRad 3000
System Check of Frequency Selective
EMC/EMF-Measurement Systems
RefRad Model 3000
the answer of ARC Seibersdorf research on the
increasing quality awareness of test labs
Dipl.-Ing. Wolfgang Müllner
1
WM 3. 11. 2004
FOR-EMC: RE-System Check with RefRad 3000
What is a System Check ?
ƒ A System Check is a quick and reliable
ƒ
method to increase the confidence in
measurement results of the test engineer
the test lab and the customer.
It detects failures in the measurement
system: receive antenna, pre-amplifier,
cable, spectrum analyser, measurement
software.
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WM 3. 11. 2004
FOR-EMC: RE-System Check with RefRad 3000
Why Do We Need a System Check ?
ƒ To gain confidence in measurement
ƒ
ƒ
ƒ
results
To detect defective instruments prior
to testing
To avoid costly re-testing
To fulfill requirements of ISO 17025
which demands a regular check of the
proper function of the test equipment
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WM 3. 11. 2004
FOR-EMC: RE-System Check with RefRad 3000
How to Perform a System Check?
ƒ
ƒ
ƒ
ƒ
Fieldstrength [dBµV/m]
emissions of a known source,
e.g. comb generator with antenna
1. Reference Measurement
2. Check Measurement
3. Comparison
4. Evaluation:
System OK or Defect
95
90
85
80
75
70
Monopole Reference(150)
65
Monopole Check(150)
60
55
1
10
100
1000
10000
1000
10000
Frequency [MHz]
100
95
Fieldstrength [dBµV/m]
ƒ Measurement of the radiated
100
90
85
80
75
70
Monopole Reference(150)
65
Monopole Defective(150)
60
55
1
10
100
Frequency [MHz]
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WM 3. 11. 2004
FOR-EMC: RE-System Check with RefRad 3000
Comb/Noise Generator with Monopole
ƒ Generally used equipment
ƒ Well suited for controlled
ƒ
ƒ
environment (anechoic chamber
Test site is part of the evaluation
Not suitable if the EUT is
already set up or for „in situ“
EMC and EMF testing
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WM 3. 11. 2004
FOR-EMC: RE-System Check with RefRad 3000
System Check: OK
100
Fieldstrength [dB µ V /m ]
95
90
85
80
75
70
Monopole Reference(150)
65
Monopole Check(150)
60
55
1
10
100
1000
10000
Frequency [MHz]
6
WM 3. 11. 2004
FOR-EMC: RE-System Check with RefRad 3000
System Check: DEFECT
100
Fieldstrength [dB µ V /m ]
95
90
85
80
75
70
Monopole Reference(150)
65
Monopole Defective(150)
60
55
1
10
100
1000
10000
Frequency [MHz]
7
WM 3. 11. 2004
FOR-EMC: RE-System Check with RefRad 3000
RefRad 3000 with Antenna Coupler
ƒ Generates a field extremely close
and at a well defined and
repeatable position at the receive
antenna
ƒ Low sensitivity to the environment
ƒ Well suitable for System Check
with set up EUT and for “in situ”
EMC and EMF testing
ƒ Patent pending
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WM 3. 11. 2004
FOR-EMC: RE-System Check with RefRad 3000
Beispiel: EMF System Check
Antenna Coupler
Antenna
Positioner
Spectrumanalyser
RefRad 3000
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WM 3. 11. 2004
FOR-EMC: RE-System Check with RefRad 3000
System Check: OK
100
Fieldstrength [dBµV/m]
95
90
85
80
75
CU8250 Reference
70
CU8250 Check
65
60
1
10
100
1000
10000
Frequency [M H z]
10
WM 3. 11. 2004
FOR-EMC: RE-System Check with RefRad 3000
System Check: DEFECT
100
Fieldstrength [dBµV/m]
95
90
85
80
75
70
CU 8250 R eference
65
CU 8250 D efective
60
1
10
100
1000
10000
Frequency [M H z]
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WM 3. 11. 2004
FOR-EMC: RE-System Check with RefRad 3000
Comparison of the System Check Methods
Generator with
Monopole
Generator with
Antenna Coupler
Easy and Fast
9
9
Check of Test Site
9
-
Reproducibility
-
9
Clear Error Distinction
-
9
Environmental
insensitive
-
9
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WM 3. 11. 2004
FOR-EMC: RE-System Check with RefRad 3000
RefRad 3000 System Components
ƒ Comb generator: battery operated,
ƒ
ƒ
ƒ
ƒ
ƒ
ƒ
stable, high power with
coaxial output connector
Antenna coupling units: for high repeatability
and high reproducibility system check
Monopole for universal function check
Protective attenuator:
20 dB for conducted measurements
Battery charger
Calibration data
Transport case
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WM 3. 11. 2004
FOR-EMC: RE-System Check with RefRad 3000
Technical Data Comb Generator
Frequency range:
Frequency spacing:
Frequency stability:
Amplitude per line (coaxial):
Amplitude stability:
Batteries:
Battery operation time:
Battery charge time:
Output Connector:
1 MHz – 3 GHz
1 MHz
50 ppm over 0 – 40°C
-18 dBm to -50 dBm
+/- 0.2 dB over battery voltage cycle
+/- 0.5 dB over 0 – 40°C
internal, NiMH
20 hours typical
6 hours
N-female
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WM 3. 11. 2004
FOR-EMC: RE-System Check with RefRad 3000
Coaxial Ouptut Power
-15
-20
Output [dBm]
-25
-30
-35
-40
-45
-50
-55
1
10
100
1000
10000
Frequency [MHz]
15
WM 3. 11. 2004