SIST EN 301 091-1 V1.3.3:2007

SLOVENSKI STANDARD
01-februar-2007
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Electromagnetic compatibility and Radio spectrum Matters (ERM); Short Range Devices;
Road Transport and Traffic Telematics (RTTT); Radar equipment operating in the 76
GHz to 77 GHz range; Part 1: Technical characteristics and test methods for radar
equipment operating in the 76 GHz to 77 GHz range
Ta slovenski standard je istoveten z: EN 301 091-1 Version 1.3.3
ICS:
33.060.99 Druga oprema za radijske Other equipment for
komunikacije radiocommunications
33.100.01 Elektromagnetna združljivost Electromagnetic compatibility
na splošno in general
35.240.60 Uporabniške rešitve IT v IT applications in transport
transportu in trgovini and trade
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);
Short Range Devices;
Road Transport and Traffic Telematics (RTTT);
Radar equipment operating in the 76 GHz to 77 GHz range;
Part 1: Technical characteristics and test methods for
radar equipment operating in the 76 GHz to 77 GHz range

2 ETSI EN 301 091-1 V1.3.3 (2006-11)

Reference
REN/ERM-TG31B-049-1
Keywords
radar, radio, testing, SRD, RTTT, short range
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3 ETSI EN 301 091-1 V1.3.3 (2006-11)
Contents
Intellectual Property Rights.5
Foreword.5
1 Scope.6
2 References.6
3 Definitions, symbols and abbreviations .7
3.1 Definitions.7
3.2 Symbols.8
3.3 Abbreviations.9
4 Technical requirements specifications.9
4.1 Equipment requirements for testing purposes .9
4.1.1 Choice of model for testing .10
4.2 Mechanical and electrical design.10
4.3 Auxiliary test equipment .10
4.4 Interpretation of the measurement results .10
5 Test conditions, power sources and ambient temperatures .10
5.1 Normal and extreme test conditions .10
5.2 External test power source.11
5.3 Normal test conditions.11
5.3.1 Normal temperature and humidity.11
5.3.2 Normal test power source .11
5.3.2.1 Mains voltage.11
5.3.2.2 Other power sources.11
5.4 Extreme test conditions .11
5.4.1 Extreme temperatures.11
5.4.1.1 Procedure for tests at extreme temperatures.11
5.4.1.2 Extreme temperature ranges.12
5.4.2 Extreme test source voltages.12
5.4.2.1 Mains voltage.12
5.4.2.2 Other power sources.12
6 General conditions.12
6.1 Test fixture.12
6.1.1 Calibration.13
6.1.2 General requirements for RF cables and waveguides .14
6.1.3 Shielded anechoic chamber.14
7 Methods of measurement and limits for transmitter parameters .15
7.1 Permitted range of operating frequencies.15
7.1.1 Definition.15
7.1.2 Method of measurement.15
7.1.3 Limits.16
7.2 Radiated spatial power density.16
7.2.1 Definition.16
7.2.2 Method of measurement.16
7.2.2.1 Equipment with a fixed beam antenna (i.e. non-steerable by either mechanical or electronic
means) .16
7.2.2.2 Equipment with (electronically or mechanically) steerable antenna(s).17
7.2.3 Limits.17
7.2.3.1 Equipment with fixed beam antenna.17
7.2.3.2 Equipment with (electronically or mechanically) steerable antennas .17
7.3 Out-of-band emissions.18
7.3.1 Definitions.18
7.3.2 Measuring receiver.18
7.3.3 Method of measurement.18
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4 ETSI EN 301 091-1 V1.3.3 (2006-11)
7.3.4 Limits.19
7.4 Radiated spurious emissions.19
7.4.1 Definition.19
7.4.2 Measuring receiver.19
7.4.3 Method of measurement for radiated spurious emissions.19
7.4.4 Limits.20
8 Receiver.20
8.1 Receiver radiated spurious emissions.20
8.1.1 Definition.20
8.1.2 Method of measurement - radiated spurious emissions .20
8.1.3 Limit.21
9 Measurement uncertainty.21
Annex A (normative): Radiated measurements .23
A.1 Test sites and general arrangements for measurements involving the use of radiated fields.23
A.1.1 Open Area Test Site (OATS) .23
A.1.2 Test antenna.24
A.1.3 Standard position.24
A.1.4 Indoor test site .24
A.2 Guidance on the use of radiation test sites .25
A.2.1 Measuring distance.25
A.2.2 Test antenna.25
A.2.3 Substitution antenna.26
A.2.4 Auxiliary cables.26
A.3 Alternative test site using a fully anechoic RF chamber .26
A.3.1 Example of the construction of a shielded anechoic chamber.26
A.3.2 Influence of parasitic reflections in anechoic chambers.27
A.3.3 Calibration of the shielded RF anechoic chamber.27
Annex B (normative): General description of measurement methods.29
B.1 Radiated measurements.29
Annex C (informative): Examples of modulation schemes.31
C.1 Pulse modulation.31
C.1.1 Definition.31
C.1.2 Typical operating parameters .31
C.2 Frequency modulated continuous wave .32
C.2.1 Definition.32
C.2.2 Typical operating parameters .32
C.3 Frequency Shift Keying (FSK).33
C.3.1 Definition.33
C.3.2 Typical operating parameters .34
C.4 PN-ASK (Pseudo-Noise Amplitude Shift Keying) 77 GHz.34
C.4.1 Definition.34
C.4.2 Typical operating parameters .35
Annex D (informative): Conversion of power density to e.i.r.p.36
D.1 Assumptions.36
D.2 Example.36
Annex E (informative): Bibliography.37
History .38

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5 ETSI EN 301 091-1 V1.3.3 (2006-11)
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).
For non EU countries the present document may be used for regulatory (Type Approval) purposes.
Where equipment compliant with the present document is intended for fitment into vehicles, then it is subject to
automotive EMC type approval under directive 2004/104/EC [5]. For use on vehicles outside the scope of
2004/104/EC [5] another EMC directive/standard appropriate for that use is required.
The present document is part 1 of a multi-part deliverable covering Electromagnetic compatibility and Radio spectrum
Matters (ERM); Short Range Devices; Road Transport and Traffic Telematics (RTTT); Radar equipment operating in
the 76 GHz to 77 GHz range, as identified below:
Part 1: "Technical characteristics and test methods for radar equipment operating in the 76 GHz to
77 GHz range";
Part 2: "Harmonized EN covering essential requirements of article 3.2 of the R&TTE Directive".

National transposition dates
Date of adoption of this EN: 22 September 2006
Date of latest announcement of this EN (doa): 31 December 2006
Date of latest publication of new National Standard
or endorsement of this EN (dop/e): 30 June 2007
Date of withdrawal of any conflicting National Standard (dow): 30 June 2007

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6 ETSI EN 301 091-1 V1.3.3 (2006-11)
1 Scope
The present document specifies the requirements for Short Range Devices (SRD) intended for Road Transport and
Traffic Telematics (RTTT) applications such as Automotive Cruise Control (ACC), Collision Warning (CW),
Anti-Collision (AC) systems, obstacle detection, Stop and Go, blind spot detection, parking aid, backup aid and other
automotive applications.
The document applies to:
a) transmitters operating in the range from 76 GHz to 77 GHz;
b) receivers operating in the range from 76 GHz to 77 GHz.
The present document contains the technical characteristics and test methods for automotive radar equipment fitted with
integral antennas operating in the frequency range from 76 GHz to 77 GHz and references CEPT/ERC/ECC
Recommendation for SRDs, CEPT/ERC/ECC Recommendation 70-03 [1] and CEPT/ECC Decision (02)01 [2].
The present document does not necessarily include all the characteristics which may be required by a user, nor does it
necessarily represent the optimum performance achievable.
The present document covers automotive radars for mobile applications in the frequency range from 76 GHz to 77 GHz.
It covers integrated transceivers and separate transmit/receive modules.
The present document covers only equipment for road vehicles.
There are two classes defined within the present document: Class 1 (e.g. FM, CW or FSK) and Class 2 (pulsed Doppler
radar only). The difference between the two class numbers is the permitted average power level.
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.
NOTE: While any hyperlinks included in this clause were valid at the time of publication ETSI cannot guarantee
their long term validity.
[1] CEPT/ERC Recommendation 70-03 (2005): "Relating to the use of Short Range Devices (SRD)".
[2] CEPT/ECC/DEC(02)01: "ECC Decision of 15 March 2002 on the frequency bands to be
designated for the coordinated introduction of Road Transport and Traffic Telematic Systems".
[3] CISPR 16: "Specifications for radio disturbance and immunity measuring apparatus and methods".
[4] ETSI TR 100 028 (all parts): "Electromagnetic compatibility and Radio spectrum Matters (ERM);
Uncertainties in the measurement of mobile radio equipment characteristics".
[5] Directive 2004/104/EC of 14 October 2004, adapting to technical progress Council Directive
72/245/EEC, relating to the radio interference (electromagnetic compatibility) of vehicles and
amending Directive 70/156/EC on the approximation of the laws of the Member States relating to
the type-approval of motor vehicles and their trailers (OJL 337, 13.11.204).
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7 ETSI EN 301 091-1 V1.3.3 (2006-11)
[6] ETSI TR 102 273-2: "Electromagnetic compatibility and Radio spectrum Matters (ERM);
Improvement on Radiated Methods of Measurement (using test site) and evaluation of the
corresponding measurement uncertainties; Part 2: Anechoic chamber".
[7] CEPT/ERC Recommendation 01-06: "Procedure for mutual recognition of type testing and type
approval for radio equipment".
[8] CEPT/ERC/Recommendation 74-01: "Unwanted emissions in the spurious domain".
3 Definitions, symbols and abbreviations
3.1 Definitions
For the purposes of the present document, the following terms and definitions apply:
antenna cycle: one complete sweep of a mechanically or electronically scanned antenna beam along a predefined
spatial path
antenna scan duty factor: ratio of the area of the beam (measured at its 3 dB point) to the total area scanned by the
antenna (as measured at its 3 dB point)
assigned frequency band: frequency band within which the device is authorized to operate
associated antenna: antenna and all its associated components which are designed as an indispensable part of the
equipment
average time: time interval on which a mean measurement is integrated
blanking period: time period where no intentional emission occurs
duty cycle: the ratio of the total on time of the "message" to the total off-time in any one hour period
dwell time: accumulated amount of transmission time of uninterrupted continuous transmission within a single given
frequency channel and within one channel repetition interval
Equipment Under Test (EUT): radar sensor including the integrated antenna together with any external antenna
components which affect or influence its performance
equivalent isotropically radiated power (e.i.r.p.): total power or power density transmitted, assuming an isotropic
radiator
NOTE: e.i.r.p. is conventionally the product of "power or power density into the antenna" and "antenna gain".
e.i.r.p. is used for both peak or average power and peak or average power density.
equivalent pulse power duration: duration of an ideal rectangular pulse which has the same content of energy
compared with the pulse shape of the EUT with pulsed modulation or time gating
far field measurements: measurement distance should be a minimum of 2d /λ , where d = largest dimension of the
antenna aperture of the EUT and λ is the operating wavelength of the EUT
mean power: supplied from the antenna during an interval of time sufficiently long compared with the lowest
frequency encountered in the modulation taken under normal operating conditions
NOTE: For pulsed systems the mean power is equal the peak envelope power multiplied by the time gating duty
factor. For CW systems without further time gating the mean power is equal the transmission power
without modulation.
on-off gating: methods of transmission with fixed or randomly quiescent period that is much larger than the PRF
operating frequency (operating centre frequency): nominal frequency at which equipment is operated
NOTE: Equipment may be able to operate at more than one operating frequency.
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8 ETSI EN 301 091-1 V1.3.3 (2006-11)
operating frequency range: range of operating frequencies over which the equipment can be adjusted through
switching or reprogramming or oscillator tuning
NOTE 1: For pulsed or phase shifting systems without further carrier tuning the operating frequency range is fixed
on a single carrier line.
NOTE 2: For analogue or discrete frequency modulated systems (FSK, FMCW) the operating frequency range
covers the difference between minimum and maximum of all carrier frequencies on which the equipment
can be adjusted.
peak envelope power: mean power (round mean square for sinusoidal carrier wave type) supplied from the antenna
during one radio frequency cycle at the crest of the modulation envelope taken under normal operating conditions
Power Spectral Density (PSD): ratio of the amount of power to the used radio measurement bandwidth
NOTE: It is expressed in units of dBm/Hz or as a power in unit dBm with respect to the used bandwidth. In case
of measurement with a spectrum analyser the measurement bandwidth is equal to the RBW.
Pulse Repetition Frequency (PRF): inverse of the Pulse Repetition Interval, averaged over a time sufficiently long as
to cover all PRI variations
Pulse Repetition Interval (PRI): time between the rising edges of the transmitted (pulsed) output power
quiescent period: time instant where no emission occurs
radiated 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. Spurious emissions
include harmonic emissions, parasitic emissions, intermodulation products and frequency conversion products, but
exclude out-of-band emissions.
radome: external protective cover which is independent of the associated antenna, and which may contribute to the
overall performance of the antenna (and hence, the EUT)
spatial radiated power density: power per unit area normal to the direction of the electromagnetic wave propagation
NOTE: It is expressed in units of W/m .
spread spectrum modulation: modulation technique in which the energy of a transmitted signal is spread throughout a
relatively large portion of the frequency spectrum
steerable antenna: Directional antenna which can sweep its beam along a predefined spatial path. Steering can be
realized by mechanical, electronical or combined means. The antenna beamwidth may stay constant or change with the
steering angle, dependent on the steering method.
3.2 Symbols
For the purposes of the present document, the following symbols apply:
λ wavelength
1/P repetition rate of the modulation wave form
ac alternating current
B bandwidth
d largest dimension of the antenna aperture
D antenna scan duty factor
D distance between ferrite beads
fb
dB decibel
dBi gain in decibels relative to an isotropic antenna
df spectral distance between 2 lines with similar power levels
∆ fmax maximum frequency shift between any two frequency steps
∆ fmin minimum frequency shift between any two frequency steps
E field strength
E reference field strength
o
G blank time period
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9 ETSI EN 301 091-1 V1.3.3 (2006-11)
P period of time during in which one cycle of the modulation wave form is completed
P mean power within the BW
a
P power of an individual spectral line
L
P radiated power
rad
R distance
R reference distance
o
τ pulse width
T chip period
c
3.3 Abbreviations
For the purposes of the present document, the following abbreviations apply:
AC Anti-Collision
ACC Automotive Cruise Control
ASK Amplitude Shift Keying
CW Continuous Wave
DSS Direct Sequence Signal
e.i.r.p. equivalent isotropically radiated power
ECC Electronic Communications Committee
EMC ElectroMagnetic Compatibility
ERC European Radiocommunication Committee
EUT Equipment Under Test
FM Frequency Modulation
FMCW Frequency Modulated Continuous Wave
FMICW Frequency Modulated Interrupted Continuous Wave
FSK Frequency Shift Keying
IF Intermediate Frequency
OATS Open Area Test Site
PN Pseudo Noise
PRF Pulse Repetition Frequency
PRI Pulse Repetition Interval
R&TTE Radio and Telecommunications Terminal Equipment
RBW Resolution Bandwidth
RF Radio Frequency
RMS Root Mean Square
RTTT Road Transport and Traffic Telematics
SRD Short Range Device
Tx Transmitter
VSWR Voltage Standing Wave Ratio
4 Technical requirements specifications
4.1 Equipment requirements for testing purposes
Each equipment submitted for testing, where applicable, shall fulfil the requirements of the present document on all
frequencies over which it is intended to operate. EMC type approval testing to Directive 2004/104/EC [5] shall be done
on the vehicle.
The provider shall provide one or more samples of the equipment, as appropriate for testing.
Additionally, technical documentation and operating manuals, sufficient to allow testing to be performed, shall be
supplied.
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10 ETSI EN 301 091-1 V1.3.3 (2006-11)
The performance of the equipment submitted for testing shall be representative of the performance of the corresponding
production model. In order to avoid any ambiguity in that assessment, the present document contains instructions for the
presentation of equipment for testing purposes, conditions of testing (see clause 5) and the measurement methods
(see clauses 7 and 8).
Stand alone equipment for testing shall be offered by the provider complete with any ancillary equipment needed for
testing. The provider shall declare the frequency range(s), the range of operation conditions and power requirements, as
applicable, in order to establish the appropriate test conditions.
The EUT will comprise the sensor, antenna and radome if needed and will be tested as a stand alone assembly. The
EUTs test fixtures may be supplied by the provider to facilitate the tests (see clause 6.1).
These clauses are intended to give confidence that the requirements set out in the document have been met without the
necessity of performing measurements on all frequencies.
4.1.1 Choice of model for testing
If an equipment has several optional features, considered not to affect the RF parameters then the tests need only to be
performed on the equipment configured with that combination of features considered to be the most complex, as
proposed by the provider and agreed by the test laboratory.
4.2 Mechanical and electrical design
The equipment submitted by the provider shall be designed, constructed and manufactured in accordance with good
engineering practice and with the aim of minimizing harmful interference to other equipment and services.
Transmitters and receivers may be individual or combination units.
4.3 Auxiliary test equipment
All necessary test signal sources and set-up information shall accompany the equipment when it is submitted for testing.
4.4 Interpretation of the measurement results
The interpretation of the results recorded on the appropriate test report for the measurements described in the present
document shall be as follows:
• the measured value relating to the corresponding limit shall be used to decide whether an equipment meets the
requirements of the present document;
• the measurement uncertainty value for the measurement of each parameter shall be included in the test report;
• the recorded value of the measurement uncertainty shall, for each measurement, be equal to, or lower than, the
figures in the table of measurement uncertainty (see clause 9).
5 Test conditions, power sources and ambient
temperatures
5.1 Normal and extreme test conditions
Testing shall be made under normal test conditions, and also, where stated, under extreme test conditions.
The test conditions and procedures shall be as specified in clauses 5.2 to 5.4.
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11 ETSI EN 301 091-1 V1.3.3 (2006-11)
5.2 External test power source
During tests the power source of the equipment shall be an external test power source, capable of producing normal and
extreme test voltages as specified in clauses 5.3.2 and 5.4.2. The internal impedance of the external test power source
shall be low enough to be negligible for its effect on the test results.
The test voltage shall be measured at the point of connection of the power cable to the equipment.
During tests the external test power source voltages shall be within a tolerance of ±1 % relative to the voltage at the
beginning of each test. The level of this tolerance can be critical for certain measurements. Using a smaller tolerance
provides a reduced uncertainty level for these measurements.
5.3 Normal test conditions
5.3.1 Normal temperature and humidity
The normal temperature and humidity conditions for tests shall be any convenient combination of temperature and
humidity within the following ranges:
• temperature: +15°C to +35°C;
• relative humidity: 20 % to 75 %.
When it is impracticable to carry out tests under these conditions, a note to this effect, stating the ambient temperature
and relative humidity during the tests, shall be added to the test report.
5.3.2 Normal test power source
The internal impedance of the test power source shall be low enough to be negligible for its effect on the test results.
For the purpose of the tests, the voltage of the external test power source shall be measured at the input terminals of the
equipment.
5.3.2.1 Mains voltage
The normal test voltage for equipment shall be the nominal mains voltage. For the purpose of the present document, the
nominal voltage shall be the declared voltage, or any of the declared voltages, for which the equipment was designed.
The frequency of the test power source corresponding to the ac mains shall be between 49 Hz and 51 Hz.
5.3.2.2 Other power sources
For operation from other power sources the normal test voltage shall be that declared by the provider. Such values shall
be stated in the test report.
5.4 Extreme test conditions
5.4.1 Extreme temperatures
5.4.1.1 Procedure for tests at extreme temperatures
Before measurements are made, the equipment shall have reached thermal balance in the test chamber. The equipment
shall not be switched off during the temperature stabilizing period.
If the thermal balance is not checked by measurements, a temperature stabilizing period of at least one hour, or such
period as may be decided by the accredited test laboratory, shall be allowed. The sequence of measurements shall be
chosen, and the humidity content in the test chamber shall be controlled so that excessive condensation does not occur.
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12 ETSI EN 301 091-1 V1.3.3 (2006-11)
5.4.1.2 Extreme temperature ranges
For tests at extreme temperatures, measurements shall be made in accordance with the procedures specified in
clause 5.4.1.1, at the upper and lower temperatures of the following limits:
• temperature: -20°C to +55°C
5.4.2 Extreme test source voltages
5.4.2.1 Mains voltage
The extreme test voltages for equipment to be connected to an ac mains source shall be the nominal mains voltage
±10 %.
5.4.2.2 Other power sources
For equipment using other power sources, or capable of being operated from a variety of power sources, the extreme
test voltages shall be that declared by the provider. These shall be recorded in the test report.
6 General conditions
Detailed descriptions of the radiated measurement arrangements are included in annexes A and B. In general,
measurements should be carried out under far field conditions; however, relative power measurements in the 76 GHz to
77 GHz frequency band could be carried out in the near field by using the test fixture as described in clause 6.1 and
shown in figure 1.
The far field condition for the EUTs is considered to be fulfilled in a radial distance that shall be a minimum of 2d /λ ,
where d = largest dimension of the antenna aperture of the EUT and λ is the operating wavelength of the EUT.
Absolute power measurements shall be made only in the far field. This prohibits the use of the test fixture shown in
figure 1.
Each test site shall meet the appropriate requirements as defined in published guidelines/standards (e.g. for OATS, the
requirements are defined in CISPR 16 [3]).
6.1 Test fixture
The test fixture for radio equipment operating in the 76 GHz to 77 GHz range enables the EUT to be physically
supported, together with a wave guide horn antenna (which is used to couple/sample the transmitted energy), in a fixed
physical relationship. The test fixture shall be designed for use in an anechoic environment and allows certain
measurements to be performed in the near field. Only relative or comparative measurements may be performed, and
only those at the frequencies in the 76 GHz to 77 GHz band over which the test fixture shall have been calibrated. A
sketch of a test fixture is depicted in figure 1.
The test fixture incorporates at least one 50 Ω RF connector and a device for electromagnetic coupling to the EUT. It
incorporates a means for repeatable positioning of the EUT. Its compactness enables the whole assembly to be
accommodated within a test chamber, usually a climatic facility. The EUT can only be confidently tested after
verification that the test fixture does not affect its performance.
At set-up, the EUT shall be aligned in the test fixture so that the maximum power is detected at the coupled output.
Orientation of the horn antenna will take into account the polarization of the EUT.
In addition, the test fixture shall provide a connection to an external power supply.
The test fixture shall be provided by the provider together with a full description, which shall meet the approval of the
selected accredited test laboratory.
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13 ETSI EN 301 091-1 V1.3.3 (2006-11)
The performance characteristics of the test fixture shall be measured and shall be approved by the accredited test
laboratory. It shall conform to the following basic parameters:
• the gain of the waveguide horn shall not exceed 20 dB;
• the physical distance between the front face of the EUT and the waveguide horn shall be between 50 cm and
60 cm;
• the physical height between the centre of the EUT and the supporting structure of the test fixture shall be
between 50 cm and 60 cm;
NOTE: Information on uncertainty contributions, and verification procedures are detailed in clauses 5 and 6,
respectively, of TR 102 273-2 [6].
• circuitry associated with the RF coupling shall contain no active or non-linear devices;
• the Voltage Standing Wave Ratio (VSWR) at the waveguide flange where measurements are made shall not be
greater than 1,5: 1 over the frequency range of the measurements;
• the performance of the test fixture when mounted in the anechoic environment on an open test site, or in a
temperature chamber, shall be unaffected by the proximity of surrounding objects or people outside the
environment. The performance shall be reproducible if the EUT is removed and then replaced;
• the performance of the test fixture shall remain within the defined limits of the calibration report, when the test
conditions are varied over the limits described in clauses 5.3 and 5.4.
6.1.1 Calibration
The calibration of the test fixture establishes the relationship between the detected output from the test fixture, and the
transmitted power (as sampled at the position of the antenna) from the EUT in the test fixture. This can be achieved by
using a calibrated horn with a gain of equal to or less than 20 dB, fed from an external signal source, in place of the
EUT to determine the variations in detected power with temperature and over frequency.
The calibration of the test fixture shall be carried out by either the provider of the EUT or the accredited test laboratory.
The results shall be approved by the accredited test laboratory.
The calibration shall be carried out over the operating frequency band, for at least three frequencies, for the declared
polarization of the EUT, and over the temperature ranges specified in clause 5.4.1.2.
Waveguide
Horn
Equipment
15 cm Pyramid
Under Test
absorber
Waveguide Interface
Flange
50 cm to 60 cm
Figure 1: Test fixture
...