GB 13837-2012 PDF in English
GB 13837-2012 (GB13837-2012) PDF English
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[GB/T 13837-2012] Sound and television broadcast receivers and associated equipment. Radio disturbance characteristics. Limits and methods of measurement
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Sound and television broadcast receivers and associated equipment -- Radio disturbance characteristics -- Limits and methods of measurement
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Limits and methods of measurement of radio interference characteristics of sound and television broadcast receivers and associated equipment
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Limits and methods of measurement of interference characteristics on sound and television broadcast reveivers and associated equipment
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Standards related to (historical): GB 13837-2012
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GB 13837-2012: PDF in English GB 13837-2012
GB
NATIONAL STANDARD OF THE
PEOPLE’S REPUBLIC OF CHINA
ICS 33.100.01
L 06
Replacing GB 13837-2003
Sound and television broadcast receivers and
associated equipment - Radio disturbance
characteristics - Limits and methods of measurement
(IEC/CISPR 13:2009, MOD)
Changed to recommended standard according to the Announcement
No.7 in 2017 by the Standardization Administration of China
ISSUED ON: DECEMBER 31, 2012
IMPLEMENTED ON: JULY 01, 2013
Issued by: General Administration of Quality Supervision, Inspection and
Quarantine;
Standardization Administration of PRC.
Table of Contents
Foreword ... 4
1 Scope ... 5
2 Normative references ... 6
3 Terms, definitions, abbreviations ... 7
3.1 Terms and definitions ... 7
3.2 Abbreviations ... 8
4 Disturbance limits ... 9
4.1 Overview ... 9
4.2 Disturbance voltage at the power supply terminal ... 9
4.3 Disturbance voltage at the antenna ... 10
4.4 Useful signal and disturbance signal voltage at RF output of equipment with
integrated or additional RF image modulator ... 11
4.5 Disturbance power ... 11
4.6 Radiated disturbance ... 12
4.7 Radiated power ... 12
5 Measurement method ... 13
5.1 Overview ... 13
5.2 Test signal ... 13
5.3 Disturbance voltage at the power supply terminal in the frequency range of
150 kHz ~ 30 MHz ... 15
5.4 Measurement of disturbance voltage at the antenna end of receivers and
related equipment with RF input in the frequency range of 30 MHz ~ 2.15 GHz 18
5.5 Measurement of useful signal and disturbance voltage at the RF output of
relevant equipment with RF image modulator in the frequency range of 30 MHz ~
2.15 GHz ... 19
5.6 Measurement of disturbance power of related equipment (except video
recorders) in the frequency range of 30 MHz ~ 1 GHz ... 20
5.7 Measurement of radiation field strength by 3m method in the frequency range
of 30 MHz ~ 1 GHz ... 22
5.8 Radiation measurement in the frequency range of 1 GHz ~ 18 GHz ... 26
5.9 Measurement of local frequency power at the input of outdoor unit ... 29
6 Explanation of CISPR radio disturbance limit... 29
6.1 Standard compliance... 29
6.2 Significance of limits ... 29
6.3 Compliance limit values on a statistical basis ... 29
Appendix A (Normative) Digital signal broadcasting receiver ... 37
Appendix B (Informative) Basic information of digital television useful signals)
... 42
Appendix C (Informative) Settings of flat-panel TV receiver ... 44
Sound and television broadcast receivers and
associated equipment - Radio disturbance
characteristics - Limits and methods of measurement
1 Scope
This standard specifies the measurement methods for sound and television
receivers and related equipment, as well as the limits for the control of
harassment from such equipment.
For multifunctional equipment, it shall meet the requirements of this standard
and/or other standards, see 4.1.
This standard is applicable to the electromagnetic energy generated by the
sound of broadcasting and similar transmissions and television receivers and
related equipment; the frequency range is 9 kHz ~ 400 GHz.
Frequencies without specified limits do not need to be measured.
The receiving system used for collective reception, especially the front end of
the cable distribution system (shared antenna TV, CATV) and the shared
receiving system (main antenna TV, MATV) belong to the category of GB 13836.
See Appendix A and Appendix B for the requirements of broadcast receivers for
receiving digital signals.
It does not include information technology equipment (ITE), even if it is
connected to a television receiver.
The telecommunications port connecting the broadcast receiver to the
telecommunications network belongs to the scope of GB 9254.
In addition, when the telecommunication port has a broadcast receiving function,
the broadcast receiving function that can be independent of the
telecommunication function shall be measured separately, meanwhile the
telecommunication function does not work during the measurement.
The PC tuner card shall be measured in accordance with the corresponding
clauses of this standard.
2 Normative references
The following documents are essential to the application of this document. For
the dated documents, only the versions with the dates indicated are applicable
to this document; for the undated documents, only the latest version (including
all the amendments) are applicable to this standard.
GB/T 3174 PAL-D system TV broadcasting technical specification
GB/T 4365 Electrotechnical terminology - Electromagnetic compatibility
(GB/T 4365-2003, IEC 60050 (161):1990, IDT)
GB 4824-2004 Industrial, scientific and medical (ISM) radio-frequency
equipment - Electromagnetic disturbance characteristics - Limits and
methods of measurement (IEC/CISPR 11:2003, IDT)
GB/T 6113.101 Specification for radio disturbance and immunity measuring
apparatus and methods - Part 1-1: Radio disturbance and immunity
measuring apparatus - Measuring apparatus (GB/T 6113.101-2008,
IEC/CISPR 16-1-1: 2006, IDT)
GB/T 6113.102 Specification for radio disturbance and immunity measuring
apparatus and methods - Part 1-2: Radio disturbance and immunity
measuring apparatus - Ancillary equipment - Conducted disturbance (GB/T
6113.102-2008, IEC/CISPR 16-1- 2:2006, IDT)
GB/T 6113.103 Specification for radio disturbance and immunity measuring
apparatus and methods - Part 1-3: Radio disturbance and immunity
measuring apparatus - Ancillary equipment - Disturbances power (GB/T
6113.103-2008, IEC/CISPR 16-1- 3:2004, IDT)
GB/T 6113.104 Specification for radio disturbance and immunity measuring
apparatus and methods - Part 1-4: Radio disturbance and immunity
measuring apparatus - Ancillary equipment - Radiated disturbance (GB/T
6113.104-2008, IEC/CISPR 16-1- 4:2005, IDT)
GB/T 6113.202 Specification for radio disturbance and immunity measuring
apparatus and methods - Part 2-2: Methods of measurement of disturbances
and immunity - Measurement of disturbance power measurement (GB/T
6113.202-2008, IEC/CISPR 16-2-2 :2004, IDT)
GB/Z 6113.403 Specification for radio disturbance and immunity measuring
apparatus and methods - Part 4-3: Uncertainties statistics and limit
modelling - Statistical considerations in the determination of EMC
compliance of bulk products (GB/Z 6113.403-2007, IEC/CISPR 16-4-3:2004,
IDT)
GB 9254 Information technology equipment - Radio disturbance
characteristics - Limits and methods of measurement (GB 9254-2008,
IEC/CISPR 22:2006, IDT)
GB 13836 Distribution systems for television and sound signals - Part 2:
Electromagnetic compatibility of equipment (GB 13836-2000, IEC 60728-
2:1997, NEQ)
GB/T 17309.1-1998 Methods of measurement on receivers for television
broadcast transmissions Part 1: General considerations Electrical
measurements at radio and video frequencies and measurements on display
performance (idt IEC 60107-1:1995)
SJ/T 11348-2006 Methods of measurement for digital television flat panel
displays
3 Terms, definitions, abbreviations
3.1 Terms and definitions
The terms and definitions as defined in GB/T 4365 as well as the following terms
and definitions apply to this document.
3.1.1
Sound broadcast receivers
The equipment used for receiving terrestrial, cable and satellite transmission
of sound broadcasting and similar services, the input signal of which may be
analog or digital.
3.1.2
Television receivers
The equipment used for receiving terrestrial, cable and satellite television
broadcasting and similar services, the input signal of which can be analog
or digital.
3.1.3
Associated equipment
A device directly connected to a sound or television receiver, or a device
capable of generating or reproducing audio or video information.
ITE: Information technology equipment
ITU-R: International telecommunication union-radio
LW, MW and SW: Long wave, medium wave and short wave
MATV: Main antenna TV
PC: Personal computer
RF: Radio frequency
4 Disturbance limits
4.1 Overview
When the method given in Chapter 5 is used for measurement, the RF
disturbance level shall not be greater than the limit specified in 4.2 ~ 4.7. At the
boundaries of the two frequency ranges overlap, the lower limit shall be used.
For mass-produced equipment, at least 80% of the products meet the limit
requirements with 80% confidence (see Chapter 6).
At the same time, the multi-function equipment that belongs to the requirements
of different clauses of this standard and/or other standards can realize each
function without changing the inside of the equipment, the test shall be carried
out independently under each function. When each function of the equipment
meets the requirements of the corresponding clauses/standards, the equipment
is considered to meet the requirements of all clauses/standards.
For equipment that cannot achieve independent operation of each function
during the test, or the independent operation of a special function will cause the
basic functions of the equipment to be impossible, at this time, if the basic
operating functions necessary for the equipment meet the requirements of the
corresponding clauses/standards, the equipment is considered to meet the
requirements.
The RMS-average limit is newly introduced. In case of dispute, the quasi-
peak/quasi-peak and average measurement results shall prevail.
4.2 Disturbance voltage at the power supply terminal
It shall be measured according to 5.3. The limits are as shown in Table 1.
frequency shall meet the requirements of the corresponding system.
For teletext, preferably use several rows of digital graphics that fill the screen,
as shown in Figure 2. If there is no such graphic, the main index page of the
national teletext broadcasting service shall be used as the test figure when
measuring, which shall be indicated in the measurement result.
For radio receivers, the standard test signal is:
a) FM: RF mono signal, 1 kHz, FM, frequency deviation 37.5 kHz;
b) LW/MW/SW: RF signal, 1 kHz, AM, modulation degree 50%;
For related equipment, the standard test signal is:
a) Audio amplifier and infrared headphones: 1 kHz sinusoidal signal;
b) Audio-related equipment, such as tape recorders, audio players, CD
players: pre-recorded tapes or records with 1 kHz audio signals, the
standard sound signal level is in accordance with the requirements of the
manufacturer of the tested equipment;
c) Video-related equipment, such as video recorders, cameras, laser video
disc players and other video disc players: pre-recorded tapes or video
discs with standard color bar TV signals with 1 kHz audio signals; the
standard sound signal level is based on the requirements of the tested
equipment manufacturer;
d) Electronic musical instrument: Use the signal generated by pressing the
high-pitched C key (about 523 Hz);
e) Infrared remote control: The typical control function continuously emits.
For the equipment for which this standard does not clearly specify its useful
signal (for example, digital signal broadcast receivers, decoders, etc.), the
nominal signal as specified in the product standard or equipment manufacturer
shall be used during the test. The manufacturer shall specify the input signal
used for the test in its technical report.
The infrared remote-control device shall be tested together as a part of the main
equipment. The infrared remote control sold separately only measures the
radiation disturbance (see Table 5).
Adjust the control buttons such as contrast, brightness and color saturation, to
produce a standard image.
The brightness values are as follows:
Black bar: 2 cd/m2
Magenta bar: 30 cd/m2
White bar: 80 cd/m2
Note 1: If the brightness value of the magenta strip in the test pattern does not
reach the specified value, its brightness shall be set as large as possible,
meanwhile the actual brightness value shall be indicated in the measurement
result.
Note 2: Refer to Appendix C for the display settings of the flat-panel TV receiver.
A television receiver with a teletext device shall be tested in a teletext mode;
the receiver displays a teletext image.
5.3.3 Sound receiver
The standard test signal used for the sound receiver is as specified in 5.2.
AM sound receivers are equipped with ferrite antennas or whip antennas. At
this time, the radiating antennas in Figures 5 and 6 shall be replaced with loop
radiating antennas or rod-shaped radiating antennas.
The volume control of the receiver under test shall be adjusted to 1/8 of the
rated audio output power; other controllers shall be placed in the middle or
neutral position; the output end shall be terminated with a resistor equal to the
rated load impedance.
When the rated load impedance of the equipment under test has a certain range,
select the rated load value that maximizes the output power of the device.
AM/FM sound receiver shall be measured in FM mode.
5.3.4 Related equipment
The standard test signal of the relevant equipment shall be as specified in 5.2.
For the relevant equipment with RF input, measure it according to the
corresponding TV or sound receiver.
The module unit (for example, tuner, frequency converter, RF amplifier, RF
equalizer, monitor, etc.) used to realize the unique functions of sound or TV
has a ground terminal, the terminal shall be grounded for measurement.
5.4 Measurement of disturbance voltage at the antenna end of
receivers and related equipment with RF input in the frequency
range of 30 MHz ~ 2.15 GHz
5.4.1 Overview
When measuring the disturbance voltage at the antenna end of the equipment
under test, an auxiliary signal generator is used to feed the RF signal (see 5.2)
to the receiver under test or the RF input of the relevant equipment; the
frequency is tuned to make the equipment under test in a normal working state.
According to the provisions of GB/T 6113.101, use a measurement receiver
with a quasi-peak detector, or as an alternative method, use a measurement
receiver with an RMS-average detector for measurement.
Adjust the output level of the auxiliary signal generator to correspond to 75 Ω
impedance, so that the signal level at the FM receiver antenna input end is 60
dBμV, meanwhile the signal level at the TV receiver antenna input end is 70
dBμV.
For FM receivers, the auxiliary signal shall be an unmodulated carrier.
5.4.2 Measurement of receiver or related equipment with coaxial antenna
input connector
Use a coaxial cable and a resistive hybrid network which has a minimum
attenuation of 6 dB to connect the antenna end of the equipment under test, the
auxiliary signal generator and the interference measuring instrument, as shown
in Figure 7.
The impedance seen from the equipment under test to the hybrid network shall
be equal to its nominal antenna input impedance.
Tune the equipment under test to receive useful signals.
Tune the interference measuring instrument to the corresponding disturbance
frequency; the measured disturbance level shall consider the attenuation value
from the antenna end of the equipment under test to the input end of the
interference measuring instrument.
Note 1: Measures shall be taken to prevent the RF current flowing from the
housing of the equipment under test to the surface of the outer conductor of the
5.5.2 Measurement method
Use a coaxial cable and a matching network (if necessary) to connect the RF
output end of the equipment under test with the input end of the interference
measuring instrument, as shown in Figure 9. The characteristic impedance of
the coaxial cable shall be the same as the nominal output impedance of the
equipment under test.
According to the provisions of GB/T 6113.101, use a measurement receiver
with a quasi-peak detector, or as an alternative method, use a measurement
receiver with an RMS-average detector for measurement.
The equipment under test shall generate an RF modulated carrier; its video
modulated signal is a vertical color bar signal (see Figure 1).
The indication value of the interference meter (tuned to the image carrier and
its harmonics) or the spectrum analyzer plus the insertion loss value of the
matching network is the RF output level.
5.6 Measurement of disturbance power of related equipment
(except video recorders) in the frequency range of 30 MHz ~ 1
GHz
5.6.1 Overview
Generally, when the frequency exceeds 30 MHz, the disturbance energy
generated by the device is transmitted to the disturbed receiver through
radiation.
Experience has shown that most of the energy is radiated from the power cords
and other connections close to the equipment. Therefore, the disturbance
power on the power cord of the equipment under test and other connections
can be used to define its disturbance level.
This power is approximately equal to the measured value at the position where
the absorbed power is the maximum by the suitable absorbing clamp fitted on
these wires.
5.6.2 Measurement method
The method is suitable for measuring the disturbance power generated by the
terminals of the related equipment; the measurement result is expressed by the
effective power; the frequency range is 30 MHz ~ 1 GHz.
For those interconnection wires whose original length is less than half the
wavelength of the lowest frequency measured, and the end of the wire is
connected to the unit without any additional wires, the moving distance of the
absorbing clamp is limited to the length of the original wire.
According to the manufacturer's instructions, only the interconnection wires
longer than the absorption clamp are required to be tested.
Note: When starting the measurement, the absorption clamp can be determined
at a certain position, then the measuring instrument can be adjusted to find the
frequency point with particularly strong disturbance.
5.6.4 Presentation of measurement results
The measurement result is expressed in dBpW. It depends on the maximum
value indicated by the interference meter and the calibration curve of the
insertion loss of the absorbing clamp.
The disturbance power level shall be the maximum value measured on the
power line or other connection at each measurement frequency.
5.7 Measurement of radiation field strength by 3m method in
the frequency range of 30 MHz ~ 1 GHz
5.7.1 Overview
The method is suitable for measuring the radiation of FM receivers, television
receivers, video recorders, etc. (see Table 5), expressed in terms of electric
field strength. This method is used for measurements in outdoor or indoor
venues with specialized facilities.
Here, the measurement method can be done in a large room without reflection
treatment or in an outdoor field with a non-metallic weather protection cover (for
example, a radome or a closed plastic cover, etc.); these fields shall meet the
requirements of 5.7.2.
During rain or snow, the outdoor climate protection site cannot be used, unless
the site attenuation test is passed, to prove that there is no significant change
in the site's RF conditions under such weather conditions.
Note: It is necessary to re-test the site attenuation regularly (appropriate period),
to determine the impact of air pollution on the RF characteristics of the outdoor
site covered by the plastic cover.
It is also possible to complete the measurement and confirm the measurement
levels of the interference meter (or the absolute value of the difference
between the two output levels of the signal generator in decibels,
corresponding to a suitable reading level Vr of the interference meter),
corresponding to a suitable output level Vg of the signal generator. Record
the measured values of the following two situations:
a) Two coaxial cables are separately connected to the transmitting and
receiving antennas;
b) Two coaxial cables are removed from their antennas and connected
together.
At the measured frequency, at and ar are the attenuation expressed in
decibels of the balun and matched attenuator at the transmitting and
receiving ends, respectively. They are only included in a) test, not included
in b) test.
For sites that meet the requirements, the deviation of the measured site
attenuation from the theoretical curve as shown in Figure 13 shall not exceed
±3 dB.
Note 2: On the high-sensitivity range, errors may be caused due to the
mismatch of the input of the interference measuring instrument, internal
noise, irrelevant signals. Therefore, the radiated power shall be high enough,
so that the interference measuring instrument used is within its sensitivity
range and the reading error does not exceed ±1.5 dB.
5.7.3 Arrangement of the equipment under test
The equipment under test is placed on a bench of non-metallic materials; the
height from the ground is 0.8 m. The equipment under test shall be able to rotate
in the horizontal plane, as shown in Figure 14.
The center of the measuring antenna and the center of the equipment under
test shall be in the same vertical plane.
As shown in Figure 14, the power cords shall be placed on the same plane. The
long power cords shall be folded back and forth in parallel with a length of 0.3
m ~ 0.4 m, fixed in a horizontal bundle at one end of the power plug.
In order not to affect the measurement accuracy, a filter that meets the
requirements shall be connected to the power supply.
Appropriate test signals are provided by a signal generator placed on the floor
below the receiver under test; the vertical cable is as short as possible to
connect to the antenna end of the receiver under test.
The interference measuring instrument shall be placed at a suitable height.
5.7.5 Measurement procedure
Starting from the front panel of the receiver under test facing the receiving
antenna, adjust the receiving antenna to a horizontally polarized position. The
height of the antenna changes within 1 m ~ 4 m, until the measuring instrument
obtains the maximum reading.
Then, rotate the equipment under test horizontally around its center, until the
measuring instrument obtains the maximum reading. Change the height of the
receiving antenna again within 1 m ~ 4 m; record the final measured maximum
value.
Turn the receiving antenna to the vertical polarization position and repeat the
above measurement steps, but the height of the antenna changes from 2 m to
4 m.
The highest value of field strength at each frequency point is measured by the
above measurement steps; which is defined as the radiation value of the
receiver under test at that point.
If the ambient signal field strength is high at the location where the receiving
antenna is located at certain frequencies, use one of the following methods to
determine whether the equipment under test meets the requirements.
a) When the frequency band of the high-level environmental signal is narrow,
the disturbance value can be interpolated according to the adjacent values;
the interpolated value shall be on the continuous function curve of the
disturbance value of the adjacent environmental noise;
b) In other cases, follow the method described in Appendix C of GB 4824-
2004.
5.8 Radiation measurement in the frequency range of 1 GHz ~
18 GHz
5.8.1 Measuring device
The equipment under test is placed on a non-metal turntable, 1 m above the
ground.
For the equipment under test that needs input signal, use a suitable signal
generator to feed the input signal to the device through a "well-shielded" cable.
placed in the same position as the actual measurement; the two antennas shall
have the same polarization and be orthogonal to the imaginary line between
them. The test shall be performed on both horizontal and vertical polarization
planes.
When the center of the transmitting antenna moves 0 cm ~ 15 cm in any
direction from its original position, if the change in the indication value of the
measuring instrument does not exceed ±1.5 dB, it is considered that the
frequency measurement site is in compliance with the requirements.
Note: Between 1 GHz and 4 GHz, the transmitting antenna shall use a half-
wave dipole or horn antenna; when above 4 GHz, it shall use a horn antenna.
When using a horn antenna, the gain higher than the half-wave dipole shall be
considered.
5.8.3 Measurement procedure
Use an antenna with horizontal polarization and vertical polarization and a
rotatable turntable on which the equipment under test is placed. Use the
substitution method for measurement. Record the maximum radiation level
measured at each frequency as a reference indication value.
Then, replace the equipment under test with a transmitting antenna (half-wave
dipole or horn antenna) with the same characteristics as the receiving antenna,
so that its center is at the original center of the equipment under test; the
transmitting antenna is connected to the standard signal through a coaxial cable
generator.
At each measuring frequency, adjust the output level of the standard signal
generator, to make the measuring instrument get the reference indication value.
At this time, the effective output power level of the standard signal generator
plus the antenna gain of the relative half-wave dipole is used as the radiation
power level of the equipment under test at the corresponding frequency.
It shall be determined that when the equipment under test is shut down, the
background noise is at least 10 dB lower than the corresponding limit, otherwise
it will affect the reading data.
When using a horn antenna instead of a dipole antenna, the measurement
result shall be expressed as the effective radiated power (ERP) of the relative
half-wave dipole.
5.8.4 Presentation of results
Use the replaced effective power to indicate the radiation level of the equipment
under test, expressed in dBpW.
Appendix A
(Normative)
Digital signal broadcasting receiver
A.1 Introduction
This Appendix gives additional information concerning measurement methods
for digital signal broadcasting receivers.
The receiver may have telecommunications or data connection ports;
meanwhile it may have storage and return channel devices.
For the measurement of non-broadcast function ports, such as
telecommunications ports or local area network (LAN) ports, measurement
shall be made with reference to corresponding standards, such as GB 9254.
A.2 Normative references
See Chapter 2 of this standard.
A.3 Terms and definitions
The following terms and definitions apply to this Appendix.
A.3.1
Digital sound receiver
Equipment used to receive digital sound broadcasting, related data and
similar services transmitted by terrestrial, cable and satellite.
A.3.2
Digital television receivers
Equipment used to receive digital television broadcasting, data and similar
services transmitted by terrestrial, cable and satellite. The receiver can have
a display (function); a receiver without a display (function) is usually called a
"set-top box".
A.3.3
Digital sound signals
A radio frequency signal modulated with a digital data stream containing
When measuring with a spectrum analyzer or a calibrated receiver, the signal
power within the nominal bandwidth shall be integrated.
A.5.3.2 Digital sound signal
The digital sound signal level is 50 dBμV.
The reference level of all sound channels is -6 dB at 1 kHz full scale.
A.5.3.3 Digital TV signal
During the test, the digital TV signal level is:
- Terrestrial system: VHF 50 dBμV, UHF 54 dBμV;
- Cable system: 60 dBμV;
- Satellite system: 60 dBμV.
The standard signal is composed of vertical color bar graphics with small motion
graphics that meet the requirements of GB/T 3174; the video bit rate is 6 Mbit/s.
The reference level of all sound channels is -6 dB at 1 kHz full scale.
For further instructions, see Appendix B.
Note: There are currently many forms of digital broadcasting (such as CMMB).
This standard does not clearly specify its useful signal. During the test, the
product standard or the nominal signal specified by the manufacturer of the
equipment under test is used. The manufacturer shall specify the input signal
used for the test in its technical report.
A.5.4 Digital and analog signal receivers
All measurements shall be performed in digital mode. When separate tuners
are used to receive digital and analog signals, the local frequency and its
harmonic emission measurements in the analog receiving mode shall be added.
......
Source: Above contents are excerpted from the PDF -- translated/reviewed by: www.chinesestandard.net / Wayne Zheng et al.
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