SIST EN 302 018-1 V1.2.1:2006

SLOVENSKI STANDARD
01-junij-2006
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Electromagnetic compatibility and Radio spectrum Matters (ERM); Transmitting
equipment for the Frequency Modulated (FM) sound broadcasting service; Part 1:
Technical characteristics and test methods
Ta slovenski standard je istoveten z: EN 302 018-1 Version 1.2.1
ICS:
33.060.20 Sprejemna in oddajna Receiving and transmitting
oprema equipment
33.100.01 Elektromagnetna združljivost Electromagnetic compatibility
na splošno in general
33.170 Televizijska in radijska Television and radio
difuzija broadcasting
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

European Standard (Telecommunications series)

Electromagnetic compatibility
and Radio spectrum Matters (ERM);
Transmitting equipment for the
Frequency Modulated (FM)
sound broadcasting service;
Part 1: Technical characteristics and test methods

2 ETSI EN 302 018-1 V1.2.1 (2006-03)

Reference
REN/ERM-TG17WG2-004-1
Keywords
audio, broadcasting, FM, radio, terrestrial,
transmitter
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ETSI
3 ETSI EN 302 018-1 V1.2.1 (2006-03)
Contents
Intellectual Property Rights.6
Foreword.6
Introduction .6
1 Scope.7
2 References.7
3 Definitions, symbols and abbreviations .8
3.1 Definitions.8
3.2 Symbols.9
3.3 Abbreviations.9
4 Technical requirements specifications.10
4.1 Environmental profile.10
4.2 Transmitter input configuration.10
4.3 Transmitter output characteristics .10
4.3.1 Rated output power.10
4.3.1.1 Definition.10
4.3.1.2 Method of measurement.10
4.3.1.2.1 Initial conditions.10
4.3.1.2.2 Procedure.11
4.3.1.2.3 Test requirements.11
4.3.1.3 Limit.11
4.3.2 Frequency drift.11
4.3.2.1 Definition.11
4.3.2.2 Method of measurement.11
4.3.2.2.1 Initial conditions.11
4.3.2.2.2 Procedure.11
4.3.2.2.3 Test requirements.11
4.3.2.3 Limit.11
4.3.3 Deviation sensitivity stability .12
4.3.3.1 Definition.12
4.3.3.2 Method of measurement.12
4.3.3.2.1 Initial conditions.12
4.3.3.2.2 Procedure.12
4.3.3.2.3 Test requirements.12
4.3.3.3 Limit.12
4.3.4 Residual AM (Hum and noise) .13
4.3.4.1 Definition.13
4.3.4.2 Method of measurement.13
4.3.4.2.1 Initial conditions.13
4.3.4.2.2 Procedure.13
4.3.4.2.3 Test requirements.13
4.3.4.3 Limit.13
4.3.5 Synchronous AM (AM due to FM) .14
4.3.5.1 Definition.14
4.3.5.2 Method of measurement.14
4.3.5.2.1 Initial conditions.14
4.3.5.2.2 Procedure.14
4.3.5.2.3 Test requirements.14
4.3.5.3 Limit.14
4.3.6 Modulator performance (pulse response) .15
4.3.6.1 Definition.15
4.3.6.2 Method of measurement.15
4.3.6.2.1 Initial conditions.15
4.3.6.2.2 Procedure.15
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4 ETSI EN 302 018-1 V1.2.1 (2006-03)
4.3.6.2.3 Test requirements.16
4.3.6.3 Limit.16
4.3.7 MPX intermodulation.16
4.3.7.1 Definition.16
4.3.7.2 Method of measurement.16
4.3.7.2.1 Initial conditions.16
4.3.7.2.2 Procedure.16
4.3.7.2.3 Test requirements.17
4.3.7.3 Limit.17
4.3.8 Deviation limiting.17
4.3.8.1 Definition.17
4.3.8.2 Method of measurement.17
4.3.8.2.1 Initial conditions.17
4.3.8.2.2 Procedure.17
4.3.8.2.3 Test requirements.18
4.3.8.3 Limit.18
4.3.9 FM Signal to Noise Ratio (SNR).18
4.3.9.1 Definition.18
4.3.9.2 Method of measurement.18
4.3.9.2.1 Initial conditions.18
4.3.9.2.2 Procedure.19
4.3.9.2.3 Test requirements.19
4.3.9.3 Limit.19
4.4 Antenna port measurements.19
4.4.1 Spurious emissions.19
4.4.1.1 Definition.19
4.4.1.2 Method of measurement (essential test suite) .19
4.4.1.2.1 Initial conditions.19
4.4.1.2.2 Procedure.20
4.4.1.2.3 Test requirements.20
4.4.1.3 Limit.20
4.4.2 Transmitter muting during frequency shift .21
4.4.2.1 Definition.21
4.4.2.2 Method of measurement (essential test suite) .21
4.4.2.2.1 Initial conditions.21
4.4.2.2.2 Procedure.22
4.4.2.2.3 Test requirements.22
4.4.2.3 Limit.22
4.4.3 Out-of-band emissions.22
4.4.3.1 Definition.22
4.4.3.2 Method of measurement (essential test suite) .22
4.4.3.2.1 Initial conditions.22
4.4.3.2.2 Procedure.23
4.4.3.2.3 Test requirements.23
4.4.3.3 Limit.24
4.5 Enclosure port measurements (radiated emissions).24
4.5.1 Cabinet radiation.24
4.5.1.1 Definition.24
4.5.1.2 Method of measurement (essential test suite) .24
4.5.1.2.1 Initial conditions.24
4.5.1.2.2 Procedure.25
4.5.1.2.3 Test requirements.25
4.5.1.3 Limit.25
4.6 Measurement uncertainties.26
Annex A (normative): General measuring arrangements.27
A.1 Testing arrangements for antenna port measurements .27
A.1.1 Testing arrangement for monophonic transmitters.27
A.1.2 Testing arrangement stereophonic transmitters .28
A.1.3 Test frequency range .29
A.1.4 Test modulating signal .29
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5 ETSI EN 302 018-1 V1.2.1 (2006-03)
A.2 Testing arrangements for enclosure port (radiated emissions) measurements .31
A.3 Test load characteristics .31
Annex B (informative): Bibliography.32
History .33

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6 ETSI EN 302 018-1 V1.2.1 (2006-03)
Intellectual Property Rights
IPRs essential or potentially essential to the present document may have been declared to ETSI. The information
pertaining to these essential IPRs, if any, is publicly available for ETSI members and non-members, and can be found
in ETSI SR 000 314: "Intellectual Property Rights (IPRs); Essential, or potentially Essential, IPRs notified to ETSI in
respect of ETSI standards", which is available from the ETSI Secretariat. Latest updates are available on the ETSI Web
server (http://webapp.etsi.org/IPR/home.asp).
Pursuant to the ETSI IPR Policy, no investigation, including IPR searches, has been carried out by ETSI. No guarantee
can be given as to the existence of other IPRs not referenced in ETSI SR 000 314 (or the updates on the ETSI Web
server) which are, or may be, or may become, essential to the present document.
Foreword
This European Standard (Telecommunications series) has been produced by ETSI Technical Committee
Electromagnetic compatibility and Radio spectrum Matters (ERM).
The present document is part 1 of a multi-part deliverable covering transmitting equipment for the Frequency
Modulated (FM) sound broadcasting service, as identified below:
Part 1: "Technical characteristics and test methods";
Part 2: "Harmonized EN under article 3.2 of the R&TTE Directive".

National transposition dates
Date of adoption of this EN: 24 February 2006
Date of latest announcement of this EN (doa): 31 May 2006
Date of latest publication of new National Standard
or endorsement of this EN (dop/e): 30 November 2006
Date of withdrawal of any conflicting National Standard (dow): 30 November 2006

Introduction
The present document covers a set of non-mandatory technical parameters that are considered to be the minimum
requirement for the design and operation of an FM sound broadcasting service.
Other documents directly associated with the present document:
- EN 302 018-2 [1];
- EN 301 489-11 [2].
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7 ETSI EN 302 018-1 V1.2.1 (2006-03)
1 Scope
The present document applies to transmitting equipment for the frequency-modulated sound broadcasting service.
The types of equipment covered by the present document are as follows:
- Transmitting equipment for frequency modulated sound broadcasting service operating in both Monophonic
and Stereophonic operating in the frequency range 68 MHz to 108 MHz.
2 References
The following documents contain provisions which, through reference in this text, constitute provisions of the present
document.
• References are either specific (identified by date of publication and/or edition number or version number) or
non-specific.
• For a specific reference, subsequent revisions do not apply.
• For a non-specific reference, the latest version applies.
Referenced documents which are not found to be publicly available in the expected location might be found at
http://docbox.etsi.org/Reference.
[1] ETSI EN 302 018-2: "Electromagnetic compatibility and Radio spectrum Matters (ERM);
Transmitting equipment for the Frequency Modulated (FM) sound broadcasting service;
Part 2: Harmonized EN under article 3.2 of the R&TTE Directive".
[2] ETSI EN 301 489-11: "Electromagnetic compatibility and Radio spectrum Matters (ERM);
ElectroMagnetic Compatibility (EMC) standard for radio equipment and services;
Part 11: Specific conditions for terrestrial sound broadcasting service transmitters".
[3] CENELEC EN 55011: "Industrial, scientific and medical (ISM) radio-frequency equipment -
Radio disturbance characteristics - Limits and methods of measurement".
[4] ITU-R Recommendation BS.468-4 (1986): "Measurement of audio-frequency noise voltage level
in sound broadcasting".
[5] IEC 60489-1: "Methods of measurement for radio equipment used in the mobile services.
Part 1: General definitions and standard conditions of measurement".
[6] ETSI TR 100 028 (all parts): "Electromagnetic compatibility and Radio spectrum Matters (ERM);
Uncertainties in the measurement of mobile radio equipment characteristics".
[7] ITU-R Recommendation SM.329: "Unwanted emissions in the spurious domain".
[8] ITU-R Recommendation BS.412: "Planning standards for terrestrial FM sound broadcasting at
VHF".
[9] ITU-R Recommendation BS.641: "Determination of radio-frequency protection ratios for
frequency-modulated sound broadcasting".
[10] ITU-R Recommendation BS.450-3 (2001): "Transmission standards for FM sound broadcasting at
VHF".
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8 ETSI EN 302 018-1 V1.2.1 (2006-03)
3 Definitions, symbols and abbreviations
3.1 Definitions
For the purposes of the present document, the following terms and definitions apply:
antenna port: port of an apparatus which is designed, in normal operation, to be connected to an antenna using coaxial
cable
broadcasting service: radio communication service in which the transmissions are intended for direct reception by the
general public
NOTE: This service may include sound transmissions, television transmissions or other types of transmission.
channel L: left hand channel of a stereophonic signal
channel R: right hand channel of a stereophonic signal
cabinet radiation: radiation from an enclosure containing, equipment, excluding radiation from connected antennas or
cables
carrier power: average power supplied to the antenna port by a transmitter during one cycle taken under the condition
of no modulation
class of emission: set of characteristics of an emission, designated by standard symbols, e.g. type of modulation of the
main carrier, modulating signal, type of information to be transmitted, and also, if appropriate, any additional signal
characteristics
composite: See "Multiplex (MPX) signal".
dBc: decibels relative to the unmodulated carrier power of the emission
NOTE: In the cases which do not have a carrier, for example in some digital modulation schemes where the
carrier is not accessible for measurement, the reference level equivalent to dBc is decibels relative to the
mean power P.
difference signal : signal (S) theoretically equal to half the difference between the left (L) and right (R) stereophonic
signals. S = (L - R) / 2
enclosure port: physical boundary of the apparatus through which electromagnetic fields may radiate or impinge
NOTE: In the case of integral antenna equipment, this port is inseparable from the antenna port.
environmental profile: range of environmental conditions under which equipment within the scope of EN 302 018-1 is
required to comply with the provisions of EN 302 018-1
exclusion band: band of radio frequencies where no measurements are made
frequency tolerance: maximum permissible departure of the characteristic frequency of an emission from the assigned
frequency
NOTE: The frequency tolerance is expressed in parts per 10 or in Hz.
harmonic: component of order greater than 1 of the Fourier series of a periodic quantity
harmonic number: integral number given by the ratio of the frequency of a harmonic to the fundamental frequency
nd
(2 harmonic = 2 × fundamental frequency)
mean power: average power supplied to the antenna port by a transmitter during an interval of time sufficiently long
compared with the lowest frequency encountered in the modulation envelope taken under normal operating conditions
MultiPleX (MPX) signal: contains all information, including the pilot tone and any supplementary signal which is used
to frequency modulate the VHF FM transmitter
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9 ETSI EN 302 018-1 V1.2.1 (2006-03)
necessary bandwidth: for a given class of emission, the width of the frequency band which is sufficient to ensure the
transmission of information at the rate and with the quality required under specified conditions
out-of-band emissions: emission on a frequency or frequencies immediately outside the necessary bandwidth which
results from the modulation process, but excluding spurious emissions
pilot tone: 19 kHz tone used to recover the stereo subcarrier in the stereo-receiver
Radio Data System (RDS): signal containing information on programmes and broadcasting network as defined in
EN 50067
NOTE: This signal is carried by a subcarrier at 57 kHz, amplitude modulated by the encoded data with
suppressed carrier in a frequency band of ±2,4 kHz.
reference bandwidth: bandwidth in which the emission level is specified
signal L: corresponds to the information in the left channel of the stereophonic signal
signal R: corresponds to the information in the right channel of the stereophonic signal
spurious emissions: emission on a frequency or frequencies which are outside the necessary bandwidth and the level of
which may be reduced without affecting the corresponding transmission of information
NOTE: Spurious emissions include harmonic emissions, parasitic emissions, intermodulation products and
frequency conversion products but exclude out of band emissions.
stereo subcarrier: 38 kHz subcarrier used to carry the difference signal
sum signal: signal (M) theoretically equal to half of the sum of the left (L) and right (R) stereophonic signals.
M = (L + R) / 2
unwanted emissions: consist of spurious emissions and out of band emissions
3.2 Symbols
For the purposes of the present document, the following symbols apply:
Ω ohms (unit of resistance)
-6
µ micro, 10
3.3 Abbreviations
For the purposes of the present document, the following abbreviations apply:
a.c. alternating current
AF Audio Frequency
AM Amplitude Modulation
dB deciBel, logarithmic ratio (tenths of a "Bel")
dBm dB relative to one milliwatt
d.c. direct current
EMC ElectroMagnetic Compatibility
EN European Norm
ERM Electromagnetic compatibility and Radio spectrum Matters
EUT Equipment Under Test
FM Frequency Modulation
Hz Hertz (cycles per second)
LV Low Voltage
MPX MultiPleX
R&TTE Radio equipment and Telecommunications Terminal Equipment
RDS Radio Data System
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10 ETSI EN 302 018-1 V1.2.1 (2006-03)
RF Radio Frequency
rms root mean square
SNR Signal to Noise Ratio
VHF Very High Frequency
V Volts
W Watt
4 Technical requirements specifications
4.1 Environmental profile
The environmental profile for operation of the equipment shall be declared by the supplier. The equipment shall comply
with all the technical requirements of the present document at all times when operating within the boundary limits of the
required operational environmental profile.
4.2 Transmitter input configuration
If the transmitter does not incorporate a stereo encoder and is intended for stereo operation then a suitable test encoder
shall be used.
4.3 Transmitter output characteristics
4.3.1 Rated output power
4.3.1.1 Definition
The rated output power is the carrier power that the EUT shall deliver at its antenna port under manufacturers specified
conditions of operation.
4.3.1.2 Method of measurement
4.3.1.2.1 Initial conditions
Test environment:
- the normal operating environment, as declared by the equipment manufacturer.
Test frequencies:
a) the lowest operating frequency of the EUT;
b) the highest operating frequency of the EUT;
c) a frequency mid-way between a) and b) above.
Test arrangement (see figure A.1):
1) connect the EUT to the Test Load, via the Coupling Device;
2) connect the Spectrum Analyser or power meter to the Coupling Device.
NOTE: AF Signal Generator and Voltage measuring equipment are not required for this test.
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11 ETSI EN 302 018-1 V1.2.1 (2006-03)
4.3.1.2.2 Procedure
1) operate the EUT at each of the test frequencies as defined in clause 4.3.1.2.1;
2) measure the results on the Spectrum Analyser or power meter.
4.3.1.2.3 Test requirements
The results obtained shall be compared to the limits in clause 4.3.1.3 in order to demonstrate compliance.
4.3.1.3 Limit
The carrier output power shall be within ±0,5 dB of the rated output power under normal operating conditions as
defined by the manufacturer.
4.3.2 Frequency drift
4.3.2.1 Definition
The frequency drift of an emission is the uncontrolled continuous and irreversible variation of frequency against a
predetermined timescale.
4.3.2.2 Method of measurement
4.3.2.2.1 Initial conditions
Test environment:
- the normal operating environment, as declared by the equipment manufacturer.
Test frequency:
- any one frequency within the tuning range of the EUT.
Test arrangement (see figure A.1):
1) connect the EUT to the Test Load, via the Coupling Device;
2) connect a frequency recorder to the Coupling Device.
NOTE: AF Signal Generator and Voltage measuring equipment are not required for this test.
4.3.2.2.2 Procedure
1) operate the exciter of the EUT at the test frequency as defined in clause 4.2.2.2.1;
2) measure the results on the frequency recorder.
4.3.2.2.3 Test requirements
The results obtained shall be compared to the limits in clause 4.3.2.3 in order to demonstrate compliance.
4.3.2.3 Limit
For a period of not less than ninety days, the frequency tolerance of the transmitter shall stay within ±300 Hz.
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12 ETSI EN 302 018-1 V1.2.1 (2006-03)
4.3.3 Deviation sensitivity stability
4.3.3.1 Definition
Stability of the required audio or MPX input level to the transmitter to achieve desired deviation.
4.3.3.2 Method of measurement
4.3.3.2.1 Initial conditions
Test environment:
- the normal operating environment, as declared by the equipment manufacturer.
Test frequencies:
a) the lowest operating frequency of the EUT;
b) the highest operating frequency of the EUT;
c) a frequency mid-way between a) and b) above.
Test arrangement (see figure A.1):
1) connect the AF Signal Generator to the EUT;
2) connect the EUT to the Test Load, via the Coupling Device;
3) connect deviation recording equipment to the Coupling Device.
4.3.3.2.2 Procedure
1) Switch the preemphasis off.
2) Using a single sinus AF the manufacturer has to define an AF input level that meets the rated deviation.
Operate the EUT with this AF input level.
3) Set the RF operating frequency constant and change the AF frequency in the range declared by the
manufacturer, but not outside the frequency range 40 Hz to 15 kHz.
4) Measure the deviation. This shall be compared to the limits in clause 4.3.3.3 a) in order to demonstrate
compliance.
For frequency agile transmitters:
1) Repeat item 3) at other RF operating frequencies including the lowest and highest operating frequency as
specified in clause 4.3.3.2.1.
2) Measure the deviation. This shall be compared to the limits in clause 4.3.3.3 b) in order to demonstrate
compliance.
4.3.3.2.3 Test requirements
The results obtained shall be compared to the limits in clause 4.3.3.3 in order to demonstrate compliance.
4.3.3.3 Limit
a) The deviation sensitivity of the transmitters shall remain within ±3 % of the declared value under the
manufacturers declared operating conditions.
b) For frequency-agile transmitters the deviation sensitivity shall remain within ±5 % of the declared value under
the manufacturers declared operating conditions.
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13 ETSI EN 302 018-1 V1.2.1 (2006-03)
4.3.4 Residual AM (Hum and noise)
4.3.4.1 Definition
The amplitude modulated hum and noise level is the peak voltage of the a.c. component at the output of a linear
envelope detector, in the absence of any modulation signal. The result is expressed as a percentage of the d.c.
component of the envelope detector output.
4.3.4.2 Method of measurement
4.3.4.2.1 Initial conditions
Test environment:
- the normal operating environment, as declared by the equipment manufacturer.
Test arrangement:
- see figure A.1 in the case where no stereo coder is present and figure A.2 in the case where a Stereo Coder is
present in the transmitter.
1) connect the EUT to the Test Load, via the Coupling Device;
2) connect a linear Envelope Detector to the Coupling Device;
3) connect a Peak Voltmeter and a d.c. Voltmeter to the output of the Envelope Detector. Alternatively, a
Modulation Meter may be used.
4.3.4.2.2 Procedure
1) if applicable, switch the stereo coder in monophonic mode;
2) check that the appropriate de- and pre-emphasis filters are in circuit;
3) no input signal is applied to the transmitter or Stereo Coder;
4) connect the audio input terminal(s) of the transmitter or Stereo Coder to a load impedance corresponding to the
nominal source impedance;
5) measure the d.c. component (U ) at the detector output which corresponds to the carrier output;
6) measure the peak a.c. voltage (U ) at the Envelope Detector output.
s
4.3.4.2.3 Test requirements
Calculate the noise and hum level by means of the following formula:
U
s
N = 100 ()%
U
When a modulation meter is used the result is indicated directly.
The results obtained shall be compared to the limits in clause 4.3.4.3 in order to demonstrate compliance.
4.3.4.3 Limit
The permitted level of residual AM in the absence of modulation shall not exceed 1 % when measured in a bandwidth
of 20 Hz to 20 kHz (unweighted).
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14 ETSI EN 302 018-1 V1.2.1 (2006-03)
4.3.5 Synchronous AM (AM due to FM)
4.3.5.1 Definition
Synchronous amplitude modulation is evaluated by measuring the peak voltage of the a.c. component at the output of a
linear envelope detector due to presence of a specified modulating signal. The result is expressed as a percentage of the
d.c. component corresponding to the unmodulated carrier.
4.3.5.2 Method of measurement
4.3.5.2.1 Initial conditions
Test environment:
- the normal operating environment, as declared by the equipment manufacturer.
Test arrangement:
- see figure A.1 in the case where no stereo coder is present and figure A.2 in the case where a stereo coder is
present in the transmitter.
1) connect the EUT to the Test Load, via the Coupling Device;
2) connect a linear Envelope Detector to the Coupling Device;
3) connect a Peak Voltmeter and a d.c. Voltmeter to the output of the Envelope Detector.
Alternatively, a Modulation Meter may be used.
4.3.5.2.2 Procedure
1) if applicable, switch the stereo coder to monophonic mode;
2) check that the appropriate de- and pre-emphasis filters are in circuit;
3) adjust input signal to a frequency within the audio-frequency band;
4) adjust input signal level for specified deviation (normally maximum deviation);
5) measure the d.c. component (U ) at the Envelope Detector output;
6) measure the a.c. component (U ) at the Envelope Detector output.
a
4.3.5.2.3 Test requirements
Calculate the amplitude modulation depth expressed as a percentage by means of the following formula:
U
a
m = 100 ()%
U
for each audio-frequency.
Present the AM depth levels as a function of the audio-frequency and state the deviation with the results.
When a modulation meter is used for the measurements, the results can be influenced by noise and hum.
The results obtained shall be compared to the limits in clause 4.3.5.3 in order to demonstrate compliance.
4.3.5.3 Limit
The permitted level of AM due to FM shall not exceed 2 % for a peak deviation of ±40 kHz at a modulation frequency
of 500 Hz.
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15 ETSI EN 302 018-1 V1.2.1 (2006-03)
4.3.6 Modulator performance (pulse response)
4.3.6.1 Definition
The amplitude and phase performance required for the transmitter to ensure compliance with the maximum frequency
deviation.
NOTE: If the amplitude and phase performance of a modulator is out of tolerance the pulse response leads to the
result of overdeviation respectively underdeviation. Overdeviation leads to a wider spectrum and in case
of clipping etc. to intermodulation products.
4.3.6.2 Method of measurement
As a measure of the modulator performance the pulse response is taken without audio processing like stereo coder and
preemphasis. Therefore the audio processing unit if existing is bridged and the MPX input of the transmitter is used.
For the measurement two test signals are taken with an amplitude that corresponds to a frequency deviation of 40 kHz.
(40 kHz is chosen in order to avoid an unwanted clipping inside the modulator due to ringing or tilt of the test signals)
The two test tones are derived from sine wave signals (40 Hz and 10 kHz) by clipping at 25 % (-12 dB) of the crest of
the sine wave. The amplitude of the clipped sine wave has to be adjusted to a level that is equal to the peak level of a
sine wave that results in a 40 kHz frequency deviation.
Alternatively to the use of the clipped sine waves, trapezoidal pulse with a slew rate that is equal to the slew rate of the
clipped sine wave, can be used.
4.3.6.2.1 Initial conditions
Test environment:
- the normal operating environment, as declared by the equipment manufacturer.
Test frequencies:
a) the lowest operating frequency of the EUT;
b) the highest operating frequency of the EUT;
c) a frequency mid-way between a) and b) above.
Test arrangement (see figure A.1):
1) connect the AF Signal Generator to the EUT;
2) connect the EUT to the Test Load, via the Coupling Device;
3) connect deviation measure equipment to the Coupling Device.
4.3.6.2.2 Procedure
1) bridge the audioprocessor or use the MPX input;
2) set the AF Signal Generator to deliver a test signal sine wave signal of 1 kHz;
3) adjust the peak sine wave signal to level that results in a modulation with 40 kHz peak deviation and determine
the peak voltage of the sine wave signal (Oscilloscope);
4) replace the sine wave signal by one of the two test tones and adjust the level of the test signal to the peak level
determined in 3);
5) measure the peak frequency from the deviation measurement equipment.
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16 ETSI EN 302 018-1 V1.2.1 (2006-03)
4.3.6.2.3 Test requirements
The resul
...