This document provides information about electromagnetic interference (EMI) measurements and standards. It discusses EMI test facilities like shielded chambers, open area test sites, and EMI receivers and spectrum analyzers used for testing. It also covers various EMI standards from organizations like CISPR, FCC, IEC, EN, and MIL for both civilian and military applications. Measurement methods for radiated and conducted emissions are described.

1. ST.JOSEPH’S COLLEGE OF
ENGINEERING & TECHNOLOGY
Thanjavur
Course Code: EC8072
NBA Course No: C409-PEIV 1
Course Name: ELECTROMAGNETIC INTERFERENCE &
COMPATIBILITY
Year / Sem / Branch / Sec: IV/ VIII/ ECE
Regulation: R2017
UNIT V
EMIC MEASUREMENTS & STANDARDS
Prepared by,
N.Srividhya, AP / ECE

2. SYLLABUS
UNIT V
EMI MEASUREMENTS AND STANDARDS 9
Open area test site; TEM cell; EMI test shielded chamber and
shielded ferrite lined anechoic chamber; Line impedance
stabilization networks; EMI Rx and spectrum analyzer; Civilian
standards - CISPR, FCC, IEC, EN; Military standards-
MIL461E/462.
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STANDARDS
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3. UNIT V
EMI MEASUREMENTS AND STANDARDS
OBJECTIVE:
 To explain the existing
standards for
Electromagnetic
Compatibility.
OUTCOME:
 Describe the various EMC
Standards and methods to
measure them.
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STANDARDS
3

4. Framing of COs
COs CO STATEMENTS LEVELS
C409-PEIV1.5
To relate the methods to measure the electromagnetic
interference.
Analyze
Level 4
C409-PEIV1.6 To recognize the various EMC standards.
Knowledge
Level 1
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5. 1
EMC Concept and
Technical Standards
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6. 2
EMC Definition
 EMC : EMC is defined as the ability of electronic and communication equipment
to be able to operate satisfactorily in the presence of interference and not be a
source of interference to nearby equipment.
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7. Electromagnetic Environment
3
Emitter Susceptor
CE Conduction
(Metallic Paths)
RE RS
(Source) (Coupling Path )
Radiation
(Nonmetallic Paths)
(Victim)
·Transmitters
·High-speed logic
·HF generators
·Power switchers
·Inductive loads
·Transients : ESD, lightening
·Conduction (current)
Common impedance
+
·Electromagnetic fields
Cross-talk/Radiation
·Receivers
·Analog circuits
·Digital circuits
·Human beings
CS
High unwanted emissions
EMI Regulation
Low susceptibility threshold
EMS Regulation
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8. The Changes of EM Environment
4
 ICT convergence : High speed/quality/definition, wireless
 Smart grid technology, new and renewable energy development
 Electric vehicles
 Energy efficiency, mobility, portability
 Automatic, social safety and security, intelligent public transportation
infrastructure
 Aerospace & avionics, ships advance
Technology
Innovation
Changes of
EM Environment
To be required the development of new EMC (testing) technologies in
electromagnetic environment
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9. EMC Problems
5
Brazil rocket explosion
Alcantara launch center
killing 21 people,
injuring 20 more
2003
Aircraft carrier explosion
USS Forrestal Disaster, Vietnam
July 29, 1967
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10. EMC Controls
• The control of electromagnetic interference (EMI) and
assurance of EMC comprises a series of related disciplines:
– Characterizing the threat.
– Setting standards for emission and susceptibility levels.
– Design for standards compliance.
– Testing for standards compliance.
• Characterization of the problem requires understanding of:
– The interference source and signal.
– The coupling path to the victim.
– The nature of the victim both electrically and in terms of the
significance of malfunction.
6
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11. EMC Tests for the Compliance
7
 Needs testing about
1) Intra-system EMC for stable operation, performance & quality
2) inter-system EMC for the protection of radio service (Radio law) and the
safety from danger regulation & certificate
EMC
Electromagnetic Compatibility
EMI
Electromagnetic Interference
CE (IEC/CISPR)
Conducted Emission
∙ Voltage
∙ Current
RS (IEC/TC77, ISO)
Radiated Susceptibility
∙ Magnetic Fields
∙ Electric Fields
CE (IEC/TC77, ISO)
Conducted Susceptibility
∙ HF/LF
∙ Surge, EFT Burst
∙ ESD
RE (IEC/CISPR)
Radiated Emission
∙ Magnetic Fields
∙ Electric Fields
∙ Conducted Power
Disturbance
EMS
Electromagnetic Susceptibility
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12. Technical Standards for EMC(1)
8
Basic Standard
- Basic standards for the measurement of radio disturbance in the frequency range
9kHz - 18GHz
ex: CISPR 16 Series, IEC/EN/K 61000-4 Series for ESD, RS/CS, Surge, EFT burst tests
Generic Standard
- Generic standards – Immunity(EMS) and emission(EMI)
for residential, commercial and light-industrial environments
ex: IEC/EN/K 61000-6-1 & IEC/EN/K 61000-6-2 for EMS
IEC/EN/K 61000-6-3 & IEC/EN/K 61000-6-4 for EMI
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13. Technical Standards for EMC(2)
9
Product Family Standard
ex: CISPR 11(ISM), CISPR 12(vehicles, boats, combustion engine), CISPR 13(EMI for broadcasting
receiver), CISPR 14-1(EMI for home appliances), CISPR 14-2(EMS for home appliances),
CISPR 15(lightening equipment), CISPR 2013(EMS for broadcasting receiver), CISPR 22(EMI for
ITE), CISPR 24(EMS for ITE), CISPR 25(vehicles, boats, combustion engine),
CISPR 32 and CISPR 35(multimedia), etc.
Product Standard
ex: IEC 60945(Maritime Navigation and Radiocommunication Equipment and Systems) ,
IEC 60533(Electrical and electronics installation in ships),
IEC 61326(Electrical equipment for measurement, control and laboratory use),
IEC 61131-2(Programmable controllers ), IEC 61204-3(Low voltage power supplies), etc.
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14. 10
EMC Regulation Issues
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15. EMC Regulation in the World
• US
– The body responsible for regulation of EMC emissions in the USA is the
Federal Communications Commission (FCC). The specific regulations are
Part 15 (Radio Frequency Devices) and Part 18 (Industrial, Scientific and
Medical Equipment) for the FCC marking.
• EU
– For the majority of electrical and electronic products, EMC requirements
in the European Union are covered by the EMC Directive (2004/108/EC)
for the CE marking
• Japan
– The body responsible for EMC emissions in Japan is the VCCI. Products
must comply with CISPR 22. Equipment intended for the domestic
environment must comply with the Class B requirements, while other
equipment should satisfy the Class A requirements
– These requirements are not mandatory regulations.
11
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16. Korea Standard Development System for EMC
12
Standard
Draft Version
Contribute
KCS
Establishing KCS
TTA Standard
(TTAS)
Establishing KS
KS Standards
Sale Requesting
KS
Standards
EMC Technical Regulation Body
RRA is the National
Committee in EMC
Field for CISPR
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17. Korea Conformity Assessment System
13
Conformity Certification (Radio Waves Act Article 58-2.2)
Conformity Registration(Radio Waves Act Article 58-2.3)
Technical Regulation : Radio and Telecommunication, SAR, EMC (Low voltage damage)
Technical Regulation : EMC (Low voltage damage)
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18. EMC Regulation in Korea
• Products Covered
– In accordance with the regulations of the South Korean KCC, the following products are
covered by the requirements for EMC certification:
• High Frequency equipment for industrial, scientific and medical use
• Automobiles and equipment powered by spark ignition engines
• Radio receiver equipment
• Domestic electrical appliances and electrical power tools
• Fluorescent lighting equipment
• High voltage equipment and accessories
• Information technology equipment
• Any other equipment
• Test Standards
– Products must comply with the appropriate South Korean standards, which are based on,
but not necessarily identical to, the appropriate CISPR standards.
14
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19. EMC Testing Facilities
15
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20. Typical EMC Test Facilities
16
Shield room
3m EMI chamber
RS chamber
30m EMI chamber
10m EMI chamber
OATS
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21. Typical Semi-Anechoic Chamber (10m)
17
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22. Semi-Anechoic Chamber (10m)
configuration
18
1 to 4 m
Antenna mast
Ground plane
EUT
direct wave
turntable
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23. Semi Anechoic Chamber Information
19
 General Information
 Dimension : 20m(L) x 12m(W) x 8.5m(H)
 Frequency Range : 30MHz ~ 18GHz
 Site Attenuation (ANSI C63.4), NSA less than ±4dB
 Site Attenuation (CISPR 13), CSA less than ±3dB
 Site Validation (CISPR 16-1-4), SVSWR less than 6dB
 Test Distance : 3m & 10m
 Test Items
 Radiated Emission
 Conducted Emission
 Standards
 ANSI C63.4
 CISPR 13
 CISPR 16-1-4
 Cost
 USD 1.7 million(about)
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24. Typical EMC test facilities layout(Top view)
20
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25. EMC test facilities construction procedure(1)
21
1. Installation of steel structure 2. Installation of shield panel[Floor] 3. Installation of scaffold
4. Installation of shield panel
[Wall & Ceiling]
5. Installation of Door, Filter 6. Performance [SE Test]
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26. EMC test facilities construction procedure(2)
22
7. Installation of Ferrite Tile 8. Installation of Absorbers 9. Installation of Raised floor
10. Installation of Groundplane 11. Finishing; Floor, interior 12. Performance [NSA Test]
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27. Typical EMS RS Chamber
23
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28. EMS RS Chamber General Information
24
 Cost
 USD 430 thousand(about)
 General Information
 Test Items  Standards
 Dimension : 9m(L) x 6m(W) x 6m(H)
 Frequency Range : 26MHz ~ 18GHz
 Field Uniformity (IEC 61000-4-3)
: (0 ~ 6)dB, over 75% of a surface
 Polarization : Vertical & Horizontal
 Uniformity Plane : 1.5m x 1.5m
 Height of the antenna : 1.55m
 Test Distance : 3m
 Radiated Susceptibility  IEC 61000-4-3
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29. Typical Screen/Shield Rooms
25
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30. Typical Shield Rooms Information
26
 Cost
 USD 260 thousand(about)
 General Information
 Test Items  Standards
 Dimension : 10m(L) x 7.5m(W) x 3m(H)
 Frequency Range : 14kHz ~ 18GHz
 Shielding Effectiveness (IEEE 299)
: more than (60 ~ 100)dB
 Measurement Point : Door, Filter, Ceiling, walls, and ventilator
 Conducted Emission
 Disturbance Power
 ESD/EFT/Surge etc.
 CISPR 14-1/13/22 etc.
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31. Typical Open-Area Test Sites(OATS)
27
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32. OATS Configuration
28
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33. OATS Information
29
 General Information
 Frequency Range : 30MHz ~ 1GHz
 Site Attenuation (ANSI C63.4), NSA less than ±4dB
 Test Distance : 3m, 10m & 30m
 Test Items
 Radiated Emission
 Standards
 ANSI C63.4
 Cost
 USD 86 thousand(about)
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34. EMC Testing Instruments
30
EMI test Receiver
Oscilloscope
Spectrum Analyzer
Signal Generator
Network Analyzer
ESD Generator
EFT/Surge Generator
Above equipments are the most commonly used available for performing EMC measurements.
LISN
Antenna
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35. EMC Tests
31
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36. Test for Radiated Emission(RE)
• RE Test for EUT
• Frequency Range : 30MHz to 1GHz(Up to
18GHz)
• Standard : CISPR 11, 12, 13, 25, 22… (EN
550XX)
EEC 95/54, SAE J 1113-41
• Major Testing System (Refer to CISPR 16)
–Test Facility : OATS, ALSE, FAR, SAR
Open area test site or
alternate test (anechoic chamber)
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37. Limit of RE
33
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38. Test for Conducted Emission(CE)
• CE Measurement emitting from cable of EUT
• Frequency Range : 150kHz to 30MHz
• Standards : CISPR 11, 13, 14, 15, 25, 22.. (EN 550XX)
• Testing System (Refer to CISPR 16)
– Test Facility : Shielded Room or adequate ground planes
– Test Equipment : EMI Receiver, Spectrum Analyzer(Quasi-peak Average
detector available)
– Other : LISN, etc.
* LISN (Line Impedance Stabilization Network) :
to create a known impedance on power lines of electrical equipment
during electromagnetic interference testing. A LISN is typically designed to
allow for measurements of the electromagnetic interference existing on
the power line.
34
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39. Limit of CE
35
Conducted Disturbance
at the Mains Ports
* Decreasing Linearly with the Logarithm of the Frequency
- The lower limit shall apply at the transition frequencies.
- Telecommunication Ports 에 대한 Limit 는 고려중임.
0.15 ~ 0.5
0.5 ~ 5
5 ~ 30
79
73
73
66
60
60
Frequency
Range
MHz
Class A
Limits dB (uV)
Q.P Average
Class B
Limits dB (uV)
Q.P Average
66 ~ 56 *
56
60
56 ~ 46
46
50
Table 1 , 2
44
48
52
56
60
64
68
72
76
80
0.1 1 10 100
Disturbance Voltage Injected
into the Mains
Calss A (Q.P)
30
0.5 5
Calss A (Average)
Calss B (Q.P)
Calss B (Average)
79
73
66
46
50
dBuV
MHz
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40. Test for Radiated Susceptibility(RS)
• Radiated field susceptibility testing typically involves a high-
powered source of RF or EM pulse energy and a radiating
antenna to direct the energy at the potential victim or
device under test (DUT).
• Frequency Range : 80 MHz to 1000 MHz
• Test condition : 1-30 V/m (1 kHz CW, 80% AM) , 100 V/m
• Standards : IEC 61000-4-3 (EN 61000-4-3), ISO 11452-2
• Test Facility : FAR
– Test Equipment : Power Amplifier system, Antenna, Field Probe
Sensor, Signal Generator, Directional Coupler, power meter,
– Other : Test software, etc
36
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41. Test for Conducted Susceptibility(CS)
• Conducted voltage and current susceptibility testing typically
involves a high-powered signal or pulse generator, and a current
clamp or other type of transformer to inject the test signal
• Frequency Range : 150kHz to 80MHz
• Test Condition : 1-10V (1kHz CW, 80% AM)
• Standards : IEC 61000-4-6 (EN 61000-4-6), ISO 7637
• Test System
– Test Facility : Shield Room
– Test Equipment : Power Amplifier system, Signal Generator,
Directional Coupler, power meter, CDN, Current Clamp
– Other : Test software, etc
37
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42. Test for Electrostatic Discharge(ESD)
• ESD is a serious issue in solid state electronics, such as integrated
circuits. Integrated circuits are made from semiconductor materials
such as silicon and insulating materials such as silicon dioxide.
Either of these materials can suffer permanent damage when
subjected to high voltages; as a result, there are now a number of
antistatic devices that help prevent static build up.
• Test Condition(input voltage) : 8kV(Air Discharge), 4kV(Contact
Discharge), Max 25kV
• Standard : IEC 61000-4-2 (EN 61000-4-2), ISO 10605
• Test System
– Test Facility : Shield Room
– Test Equipment : ESD Simulator, Coupling Plane
– Other : Capacitors, Resistors, etc
38
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43. What i s a Spectrum Analyzer?
A spectrum analyzer measures the magnitude of an
input signal versus frequency within the full
frequency range of the instrument.
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44. Measurement Categories
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45. 13 November 2022
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46. Analysis Domains
Time Domain (Oscilloscope)
• See what changes in time.
• If signal has many frequencies ,analysis
become difficult.
Frequency Domain (Spectrum analyzer)
• Each element of a complex signal can be
separated easily.
• Low-level distortion signals can be
detected.
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47. Analysis Domains
Modulation Domain (Modulation analyzer)
• See how frequency changes.
• Measures modulation accuracy
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48. 13 November 2022
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49. D i ffe re nt Types o f Analyzers
1 Fourier TransformAnalyzer
2 Swept-Tuned Analyzer
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50. Parallel filters measured
simultaneously
CRT shows full
spectral display
A
f
f1 f2
Fourier Analyzer
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51. Fourier Analyzer
• The Fourier analyzer basically takes a
time-domain signal, digitizes it using digital
sampling, and then performs the
mathematics required to convert it to the
frequency domain, and display the
resulting spectrum.
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52. Fourier Analyzer
• It is as if the analyzer is looking at the
entire frequency range at the same time
using parallel filters measuring
simultaneously.
• The Fourier analyzer is able to capture
periodic as well as random and transient
events.
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53. Fourier Analyzer
• However it does have its limitations,
particularly in the areas of frequency
range, sensitivity, and dynamic range.
• Fourier analyzers are becoming more
prevalent, as ADC converters and DSP
technologies advance.
• These analyzers can offer significant
performance improvements over
conventional spectrum analyzers, but
often with a price premium.
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54. A
f
f1
f2
Filter 'sweeps' over range
of interest
CRT shows full
spectral display
Swept Analyzer
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55. Swept Analyzer
• The most common type of spectrum
analyzer is the swept-tuned receiver,
displaying all the frequency components
present.
• The swept-tuned analyzer works just like
the AM radio in your home except that on
your radio, the dial controls the tuning and
instead of a display, your radio has a
speaker.
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56. Spectrum Analyzer Block Diagram
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57. Mixer
• The output frequencies that will be produced by the
mixer are the original input signals, plus the sum and
difference
frequencies of these two signals.
• It is the difference frequency that is of interest in the
spectrum analyzer.
• We call this signal the IF signal, or Intermediate
Frequency signal.
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58. IF F i l t e r
• The IF filter is a band pass filter which is used as
the "window" for detecting signals. It's bandwidth
is also called the resolution bandwidth (RBW) of
the analyzer and can be changed via the front
panel of the analyzer.
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59. Envelope Detector
• The analyzer must covert the IF signal to a baseband or
video signal so it can be digitized and then viewed on the
analyzer display. This is accomplished with an envelope
detector whose video output is then digitized with an
ADC.
• The digitized output of the ADC is then represented as
the signal’s amplitude on the Y-axis of the display. This
allows for several different detector modes of how the
signal is displayed.
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60. Video F i l t e r
• The video filter is a low-pass filter that is
located after the envelope detector and
before the ADC. This filter determines the
bandwidth of the video amplifier, and is
used to average or smooth the trace seen
on the screen.
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61. Other Components
• The local oscillator (LO) s a Voltage Controlled
Oscillator (VCO) which in effect tunes the
analyzer. The sweep generator actually tunes
the LO so that its frequency changes in
proportion to the ramp voltage.
• The RF attenuator attenuates the input signal to
a suitable mixer input level.
• The IF gain is used to adjust the vertical position
of signals on the display without affecting the
signal level at the input mixer.
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62. Theory o f Operation
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63. Theory o f Operation
• The signal to be analyzed is connected to
the input of the analyzer.
• This signal is then combined with the LO
through the mixer to convert it to an IF.
• These signals are then sent to the IF filter,
whose output is detected, indicating the
presence of a signal at the analyzer's
tuned frequency.
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64. Theory o f Operation
• The output voltage of the detector drives
the vertical axis (amplitude) of the LCD
display.
The sweep generator provides
synchronization between the horizontal
axis (frequency) and tuning of the LO.
• The resulting display shows amplitude
versus frequency of the spectral
components of each incoming signal.
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65. Specifications
1) what's the frequency range?
2)what's the amplitude range (maximum
input and sensitivity)?
3)to what level can I measure the
difference
between two signals, both in amplitude
(dynamic range) and frequency
(resolution)?
4)how accurate are my measurements once
I've made them?
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66. Frequency Range-
Resolution
• The range of frequencies that device
works on.
• Resolution is an important specification when
you are trying to measure signals that are close
together and want to be able to distinguish
them from each other.
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67. Sensiti v i t y
• One of the primary uses of a spectrum analyzer is to
search out and measure low-level signals.
• The sensitivity of any receiver is an indication of how
well it can measure small signals.
• A perfect receiver would add no additional noise to the
natural amount of thermal noise present in all electronic
systems.
• In practice, all receivers, including spectrum analyzers,
add some amount of internally generated noise.
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69. Dynamic Range
• Dynamic Range is defined as the maximum ratio of two
signal levels simultaneously present at the input which
can be measured to a specified accuracy. You can
imagine connecting two signals to the analyzer input -
one which is the maximum allowable level for the
analyzer's input range and the other which is much
smaller. The smaller one is
reduced in amplitude until it is no longer detectable by
the analyzer. When the smaller signal is just
measurable, the
ratio of the two signal levels (in dB) defines the dynamic
range of the analyzer.
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