IEC 62037-8:2025

IEC 62037-8 ®
Edition 2.0 2025-03
REDLINE VERSION
INTERNATIONAL
STANDARD
Passive RF and microwave devices, intermodulation level measurement –
Part 8: Measurement of passive intermodulation generated by objects exposed
to RF radiation
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IEC 62037-8 ®
Edition 2.0 2025-03
REDLINE VERSION
INTERNATIONAL
STANDARD
Passive RF and microwave devices, intermodulation level measurement –
Part 8: Measurement of passive intermodulation generated by objects exposed
to RF radiation
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 33.120.01 ISBN 978-2-8327-0321-2

– 2 – IEC 62037-8:2025 RLV © IEC 2025
CONTENTS
FOREWORD . 3
1 Scope . 5
2 Normative references . 5
3 Terms, definitions and abbreviated terms . 5
3.1 Terms and definitions . 5
3.2 Abbreviated terms . 5
4 General considerations . 6
4.1 Test environment . 6
4.2 Safety . 6
5 Test set-up . 6
5.1 Test configurations . 6
5.1.1 General . 6
5.1.2 Antenna type . 7
5.1.3 Antenna directivity . 8
5.1.4 Antenna VSWR . 8
5.1.5 Antenna polarization . 8
5.1.6 DUT location . 8
5.1.7 DUT orientation . 9
5.2 Dynamic stimulus . 10
5.3 Verification tests . 11
5.3.1 Residual PIM verification . 11
5.3.2 VSWR verification . 11
6 Test specification . 11
7 Report . 11
Bibliography . 12

Figure 1 – Radiated PIM test set-up, single antenna, single band . 7
Figure 2 – Radiated PIM test set-up, dual antenna, dual band . 7
Figure 3 – Radiated PIM test set-up, dual antenna, single band . 7
Figure 4 – Test zone definition . 9
Figure 5 – Flat object or device definition . 10
Figure 6 – Rotate antenna or DUT to change polarization . 10

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
PASSIVE RF AND MICROWAVE DEVICES,
INTERMODULATION LEVEL MEASUREMENT –

Part 8: Measurement of passive intermodulation
generated by objects exposed to RF radiation

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote international
co-operation on all questions concerning standardization in the electrical and electronic fields. To this end and
in addition to other activities, IEC publishes International Standards, Technical Specifications, Technical Reports,
Publicly Available Specifications (PAS) and Guides (hereafter referred to as "IEC Publication(s)"). Their
preparation is entrusted to technical committees; any IEC National Committee interested in the subject dealt with
may participate in this preparatory work. International, governmental and non-governmental organizations liaising
with the IEC also participate in this preparation. IEC collaborates closely with the International Organization for
Standardization (ISO) in accordance with conditions determined by agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence between
any IEC Publication and the corresponding national or regional publication shall be clearly indicated in the latter.
5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
services carried out by independent certification bodies.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) IEC draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). IEC takes no position concerning the evidence, validity or applicability of any claimed patent rights in
respect thereof. As of the date of publication of this document, IEC had not received notice of (a) patent(s), which
may be required to implement this document. However, implementers are cautioned that this may not represent
the latest information, which may be obtained from the patent database available at https://patents.iec.ch. IEC
shall not be held responsible for identifying any or all such patent rights.
This redline version of the official IEC Standard allows the user to identify the changes
made to the previous edition IEC 62037-8:2022. A vertical bar appears in the margin
wherever a change has been made. Additions are in green text, deletions are in
strikethrough red text.
– 4 – IEC 62037-8:2025 RLV © IEC 2025
IEC 62037-8 has been prepared by technical committee 46: Cables, wires, waveguides, RF
connectors, RF and microwave passive components and accessories. It is an International
Standard.
This second edition cancels and replaces the first edition published in 2022. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) added safety warning to verify that transmitters are switched off before connecting or
disconnecting any component;
b) corrected formula for calculating directivity;
c) corrected antenna orientation labels in Figure 6;
d) added clarification that PIM tests reports shall include maximum PIM and VSWR values.
The text of this International Standard is based on the following documents:
Draft Report on voting
46/1039/FDIS 46/1045/RVD
Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this International Standard is English.
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detail at www.iec.ch/publications.
A list of all parts in the IEC 62037 series, published under the general title Passive RF and
microwave devices, intermodulation level measurement, can be found on the IEC website.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under webstore.iec.ch in the data related to the
specific document. At this date, the document will be
• reconfirmed,
• withdrawn, or
• revised.
PASSIVE RF AND MICROWAVE DEVICES,
INTERMODULATION LEVEL MEASUREMENT –

Part 8: Measurement of passive intermodulation
generated by objects exposed to RF radiation

1 Scope
This part of IEC 62037 defines a radiated passive intermodulation (PIM) test to determine PIM
levels generated by a device or object when it is exposed to RF radiation. This test can be
conducted on any material or object and is not limited to devices designed to propagate RF
signals. This test can be conducted as either a near field or far field test as defined by the test
specification in an outdoor test site or in an anechoic test chamber.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies.
For undated references, the latest edition of the referenced document (including any
amendments) applies.
IEC 62037-1, Passive RF and microwave devices, intermodulation level measurement – Part 1:
General requirements and measuring methods
IEC 62037-6:2021, Passive RF and microwave devices, intermodulation level measurement –
Part 6: Measurement of passive intermodulation in antennas
3 Terms, definitions and abbreviated terms
3.1 Terms and definitions
No terms and definitions are listed in this document.
ISO and IEC maintain terminology databases for use in standardization at the following
addresses:
• IEC Electropedia: available at https://www.electropedia.org/
• ISO Online browsing platform: available at https://www.iso.org/obp
3.2 Abbreviated terms
AIM active intermodulation
DUT device under test
IM intermodulation
PIM passive intermodulation
VSWR voltage standing wave ratio

– 6 – IEC 62037-8:2025 RLV © IEC 2025
4 General considerations
4.1 Test environment
When applicable, radiated PIM measurements can be accomplished outdoors. In performing
such a test, it is important to ensure that government regulations pertaining to the maximum
authorized RF radiation levels are met. These measurements can be subject to regulatory
requirements with regard to authorized RF radiation levels. Also, the RF energy radiated by the
test antenna can generate PIM in surrounding structures other than the device under test (DUT)
which can couple back into the test antenna resulting in invalid PIM test results. Additionally,
external sources of RF radiation can interfere with the test measurements. A survey of the
frequencies and power magnitude locally in use is recommended prior to testing. External
sources of PIM in the test environment can be minimized or eliminated by performing the test
within an anechoic test chamber providing a low PIM test environment. More information on the
construction of anechoic test chambers suitable for PIM testing is provided in IEC 62037-6:2021,
6.8.
4.2 Safety
Performing PIM tests with antenna products can be dangerous. Potentially high voltages and
high levels of RF energy can be present within the test environment. The DUT should be
positioned such that personnel will not be exposed to electromagnetic fields exceeding the
acceptable levels specified by government agencies are not exposed to unsafe levels of
electromagnetic fields, the maximum acceptable levels of which can be subject to governmental
specifications. Personnel should verify that the transmitters are switched off before connecting
or disconnecting any component.
5 Test set-up
5.1 Test configurations
5.1.1 General
A typical test set-up for radiated PIM testing is shown in Figure 1. Low PIM components should
be used to construct the test system and the overall cable or waveguide lengths should be
minimized to deliver maximum power to the transmitting antenna. Sufficient isolation shall be
provided between the transmit (Tx) and receive (Rx) paths to prevent active intermodulation
(AIM) within the test system receiver.
A second set-up for radiated PIM testing is shown in Figure 2. This configuration can be used
to measure intermodulation (IM) products that are outside of the operating bandwidth of the
transmitting antenna.
A third set-up for radiated PIM testing is shown in Figure 3. This configuration can be used
when the residual PIM of the test antenna is higher than desired, preventing accurate
measurement of the DUT.
Figure 1 – Radiated PIM test set-up, single antenna, single band

Figure 2 – Radiated PIM test set-up, dual antenna, dual band

Figure 3 – Radiated PIM test set-up, dual antenna, single band
5.1.2 Antenna type
The transmit and receive antenna(s) will shall be directional panel or horn type antennas.

– 8 – IEC 62037-8:2025 RLV © IEC 2025
5.1.3 Antenna directivity
The transmit and receive antenna directivity will shall be 10,25 dBi ± 3,0 dBi at the f , f and IM
1 2
product test frequencies, where directivity, dir, is calculated as follows:
Directivity = 4 1253 / (BW × BW )
A E
dir = 41 253 / (BW × BW )
A E
where
BW is the half power azimuth beam width of test antenna;
A
BW is the half power elevation beam width of test antenna.
E
5.1.4 Antenna VSWR
The transmit and receive antenna voltage standing wave ratio (VSWR) shall be less than 1,92:1
(10 dB return loss) at the f f and IM product test frequencies when measured in the test
1, 2
environment excluding the DUT and DUT support structure (if required).
5.1.5 Antenna polarization
The transmit and receive antennas shall be linearly polarized. If separate transmit and receive
antennas are used, the two antennas will shall be co-polarized while measuring PIM.
5.1.6 DUT location
5.1.6.1 DUT distance from transmit antenna
5.1.6.1.1 General
Radiated PIM tests can be conducted in either the near field or the far field region of the test
system transmit antenna. Distance is defined as the shortest direct path between the front face
of the transmit antenna and the closest point on the DUT. Unless otherwise specified, The
following test distance ranges will shall be used for far field and near field tests.
5.1.6.1.2 Far field test
Far field tests will be conducted within a distance range of 2 × D /λ ± 0,25 × λ, where λ is the
lowest f or f test frequency wavelength and D is the largest linear dimension of the transmit
1 2
antenna.
The far field test distance range, TD , is calculated as follows:
ff
TD = 2 × D /λ ± 0,25 × λ
ff
where
λ is the wavelength of the lowest f or f test frequency;
1 2
D is the largest linear dimension of the transmit antenna.
5.1.6.1.3 Near field test
Near field tests will be conducted at a distance of 1 × λ ± 0,1 × λ, where λ is the lowest f or f
1 2
test frequency wavelength.
The near field test distance range, TD , is calculated as follows:
nf
TD = 1 × λ ± 0,1 × λ
nf
where
λ is the wavelength of the lowest f or f test frequency.
1 2
5.1.6.2 DUT location within the antenna beam
The centre of the DUT will be positioned at the centre of the transmit antenna's main beam with
no part of the DUT extending outside of the transmit antenna's half-power azimuth or elevation
beam widths, as shown in Figure 4. If the DUT is too large to meet this requirement, it is
acceptable to move the DUT and repeat the test until all areas of the DUT have been exposed
to the required level of RF energy. It is acceptable to move the DUT while PIM testing to meet
this requirement if human safety is not at risk.
Maximum test zone width, w , is calculated as follows:
tz,max
w = D + 2 × S × Tan (BW / 2)
tz,max MIN A
where
D is the test antenna width or height, whichever is smaller;
MIN
S is the separation between antenna and DUT;
BW is the half power azimuth beam width of test antenna.
A
Maximum test zone height, h , is calculated as follows:
tz,max
h = D + 2 × S × Tan (BW / 2)
tz,max MIN E
where
D is the test antenna width or height, whichever is smaller;
MIN
S is the separation between antenna and DUT;
BW is the half power elevation beam width of test antenna.
E
Figure 4 – Test zone definition
5.1.7 DUT orientation
During the radiated PIM test, devices/objects should the device or object shall be positioned in
front of the test antenna in an orientation that simulates how the device or object would normally
be oriented in the field.
– 10 – IEC 62037-8:2025 RLV © IEC 2025
5.1.7.1 DUT surfaces to radiate
5.1.7.1.1 Flat objects or devices
Flat objects or devices are those whose vertical and horizontal aspect ratios (h/t and w/t) are
. The radiated PIM test will shall be conducted on the front
greater than 10 as shown in Figure 5
and rear surfaces (DUT rotated 180°) only for flat objects or devices.
w / t > 10
and
h / t > 10
Figure 5 – Flat object or device definition
5.1.7.1.2 Non-flat objects or devices
For non-flat objects or devices, the radiated PIM test will shall be conducted on the front surface,
left surface (DUT rotated 90°), right surface (DUT rotated −90°) and rear surface (DUT rotated
180°). The top and bottom surfaces are not tested, unless otherwise specified.
5.1.7.2 DUT orientation relative to antenna polarization
Radiated PIM tests will shall be conducted at two orthogonal polarizations for each DUT surface
tested. This can be accomplished by rotating the transmit and receive antenna(s) by 90°, by
radiating the DUT with orthogonal polarization ports of a dual polarized antenna, or by rotating
the DUT by 90° as shown in Figure 6. It is acceptable to rotate the DUT while testing to meet
this requirement.
Figure 6 – Rotate antenna or DUT to change polarization
5.2 Dynamic stimulus
A dynamic stimulus shall be applied while performing a radiated PIM test. The purpose for
applying a dynamic stimulus is to identify the presence of any loose metal-to-metal contacts
within the device or object. The stimulus does not have to simulate in-use conditions to identify
loose connections. Tap tests, flex tests, impact tests or vibration tests are all acceptable
stimulus methods. A dynamic stimulus will shall be selected that is appropriate for the type and
form of the object or device under test. The test specification will describe how and where the
dynamic stimulus is applied as well as the number of cycles or test duration.

5.3 Verification tests
5.3.1 Residual PIM verification
Prior to performing a radiated PIM test, measure the residual PIM of the test set-up including
the test environment and DUT support structure (if required). The residual PIM of the test set-
up shall be a minimum of 10 dB lower than the PIM level to be certified in accordance with
IEC 62037-1.
5.3.2 VSWR verification
Prior to performing a radiated PIM test, measure the VSWR of the test environment including
the transmit and receive antenna(s), the RF cable(s) feeding the test antenna(s), the DUT
support structure (if required). The VSWR at the f , f and IM product test frequencies should
1 2
be less than 1,92:1 (10 dB return loss).
6 Test specification
Test specifications shall specify:
a) test type: near field or far field;
b) dynamic stimulus:
• describes how and where the dynamic stimulus is applied;
• specifies the number of dynamic stimulus cycles or the test duration;
c) test power level;
d) IM product order to be measured;
e) frequency band(s) or specific test frequencies within the band(s) to be measured;
f) pass/fail IM product level.
It is possible that unique test configurations may be are required to better simulate operating
conditions. For those cases, the test specification will need to shall document any changes
relative to this specification.
7 Report
The report shall document the following:
a) description of device or object tested;
b) object or device type (flat or non-flat);
c) test type: near field or far field;
d) test power level;
e) IM product measured;
f) pass/fail IM product level;
g) dynamic stimulus;
h) for each band tested:
• test frequencies (f , f and IM product);
1 2
• residual PIM of the test set-up for each polarization;
• peak maximum PIM measured for each DUT surface and polarization;
• peak maximum VSWR (or return loss) at the f , f and IM product test frequencies of the
1 2
setup without DUT;
i) any differences between the actual test method or test configuration and this specification.

– 12 – IEC 62037-8:2025 RLV © IEC 2025
Bibliography
IEC 62037-6:2021, Passive RF and microwave devices, intermodulation level measurement –
Part 6: Measurement of passive intermodulation in antennas

___________
IEC 62037-8 ®
Edition 2.0 2025-03
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Passive RF and microwave devices, intermodulation level measurement –
Part 8: Measurement of passive intermodulation generated by objects exposed
to RF radiation
Dispositifs RF et à micro-ondes passifs, mesure du niveau d’intermodulation –
Partie 8: Mesure de l’intermodulation passive générée par des objets exposés au
rayonnement RF
– 2 – IEC 62037-8:2025 © IEC 2025
CONTENTS
FOREWORD . 3
1 Scope . 5
2 Normative references . 5
3 Terms, definitions and abbreviated terms . 5
3.1 Terms and definitions . 5
3.2 Abbreviated terms . 5
4 General considerations . 6
4.1 Test environment . 6
4.2 Safety . 6
5 Test set-up . 6
5.1 Test configurations . 6
5.1.1 General . 6
5.1.2 Antenna type . 7
5.1.3 Antenna directivity . 8
5.1.4 Antenna VSWR . 8
5.1.5 Antenna polarization . 8
5.1.6 DUT location . 8
5.1.7 DUT orientation . 9
5.2 Dynamic stimulus . 10
5.3 Verification tests . 11
5.3.1 Residual PIM verification . 11
5.3.2 VSWR verification . 11
6 Test specification . 11
7 Report . 11
Bibliography . 12

Figure 1 – Radiated PIM test set-up, single antenna, single band . 7
Figure 2 – Radiated PIM test set-up, dual antenna, dual band . 7
Figure 3 – Radiated PIM test set-up, dual antenna, single band . 7
Figure 4 – Test zone definition . 9
Figure 5 – Flat object or device definition . 10
Figure 6 – Rotate antenna or DUT to change polarization . 10

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
PASSIVE RF AND MICROWAVE DEVICES,
INTERMODULATION LEVEL MEASUREMENT –

Part 8: Measurement of passive intermodulation
generated by objects exposed to RF radiation

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote international
co-operation on all questions concerning standardization in the electrical and electronic fields. To this end and
in addition to other activities, IEC publishes International Standards, Technical Specifications, Technical Reports,
Publicly Available Specifications (PAS) and Guides (hereafter referred to as "IEC Publication(s)"). Their
preparation is entrusted to technical committees; any IEC National Committee interested in the subject dealt with
may participate in this preparatory work. International, governmental and non-governmental organizations liaising
with the IEC also participate in this preparation. IEC collaborates closely with the International Organization for
Standardization (ISO) in accordance with conditions determined by agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence between
any IEC Publication and the corresponding national or regional publication shall be clearly indicated in the latter.
5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
services carried out by independent certification bodies.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) IEC draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). IEC takes no position concerning the evidence, validity or applicability of any claimed patent rights in
respect thereof. As of the date of publication of this document, IEC had not received notice of (a) patent(s), which
may be required to implement this document. However, implementers are cautioned that this may not represent
the latest information, which may be obtained from the patent database available at https://patents.iec.ch. IEC
shall not be held responsible for identifying any or all such patent rights.
IEC 62037-8 has been prepared by technical committee 46: Cables, wires, waveguides, RF
connectors, RF and microwave passive components and accessories. It is an International
Standard.
This second edition cancels and replaces the first edition published in 2021. This edition
constitutes a technical revision.

– 4 – IEC 62037-8:2025 © IEC 2025
This edition includes the following significant technical changes with respect to the previous
edition:
a) added safety warning to verify that transmitters are switched off before connecting or
disconnecting any component;
b) corrected formula for calculating directivity;
c) corrected antenna orientation labels in Figure 6;
d) added clarification that PIM tests reports shall include maximum PIM and VSWR values.
The text of this International Standard is based on the following documents:
Draft Report on voting
46/1039/FDIS 46/1045/RVD
Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this International Standard is English.
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detail at www.iec.ch/publications.
A list of all parts in the IEC 62037 series, published under the general title Passive RF and
microwave devices, intermodulation level measurement, can be found on the IEC website.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under webstore.iec.ch in the data related to the
specific document. At this date, the document will be
• reconfirmed,
• withdrawn, or
• revised.
PASSIVE RF AND MICROWAVE DEVICES,
INTERMODULATION LEVEL MEASUREMENT –

Part 8: Measurement of passive intermodulation
generated by objects exposed to RF radiation

1 Scope
This part of IEC 62037 defines a radiated passive intermodulation (PIM) test to determine PIM
levels generated by a device or object when it is exposed to RF radiation. This test can be
conducted on any material or object and is not limited to devices designed to propagate RF
signals. This test can be conducted as either a near field or far field test as defined by the test
specification in an outdoor test site or in an anechoic test chamber.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies.
For undated references, the latest edition of the referenced document (including any
amendments) applies.
IEC 62037-1, Passive RF and microwave devices, intermodulation level measurement – Part 1:
General requirements and measuring methods
3 Terms, definitions and abbreviated terms
3.1 Terms and definitions
No terms and definitions are listed in this document.
ISO and IEC maintain terminology databases for use in standardization at the following
addresses:
• IEC Electropedia: available at https://www.electropedia.org/
• ISO Online browsing platform: available at https://www.iso.org/obp
3.2 Abbreviated terms
AIM active intermodulation
DUT device under test
IM intermodulation
PIM passive intermodulation
VSWR voltage standing wave ratio

– 6 – IEC 62037-8:2025 © IEC 2025
4 General considerations
4.1 Test environment
When applicable, radiated PIM measurements can be accomplished outdoors. These
measurements can be subject to regulatory requirements with regard to authorized RF radiation
levels. Also, the RF energy radiated by the test antenna can generate PIM in surrounding
structures other than the device under test (DUT) which can couple back into the test antenna
resulting in invalid PIM test results. Additionally, external sources of RF radiation can interfere
with the test measurements. A survey of the frequencies and power magnitude locally in use is
recommended prior to testing. External sources of PIM in the test environment can be minimized
or eliminated by performing the test within an anechoic test chamber providing a low PIM test
environment. More information on the construction of anechoic test chambers suitable for PIM
testing is provided in IEC 62037-6:2021, 6.8.
4.2 Safety
Performing PIM tests with antenna products can be dangerous. Potentially high voltages and
high levels of RF energy can be present within the test environment. The DUT should be
positioned such that personnel are not exposed to unsafe levels of electromagnetic fields, the
maximum acceptable levels of which can be subject to governmental specifications. Personnel
should verify that the transmitters are switched off before connecting or disconnecting any
component.
5 Test set-up
5.1 Test configurations
5.1.1 General
A typical test set-up for radiated PIM testing is shown in Figure 1. Low PIM components should
be used to construct the test system and the overall cable or waveguide lengths should be
minimized to deliver maximum power to the transmitting antenna. Sufficient isolation shall be
provided between the transmit (Tx) and receive (Rx) paths to prevent active intermodulation
(AIM) within the test system receiver.
A second set-up for radiated PIM testing is shown in Figure 2. This configuration can be used
to measure intermodulation (IM) products that are outside of the operating bandwidth of the
transmitting antenna.
A third set-up for radiated PIM testing is shown in Figure 3. This configuration can be used
when the residual PIM of the test antenna is higher than desired, preventing accurate
measurement of the DUT.
Figure 1 – Radiated PIM test set-up, single antenna, single band

Figure 2 – Radiated PIM test set-up, dual antenna, dual band

Figure 3 – Radiated PIM test set-up, dual antenna, single band
5.1.2 Antenna type
The transmit and receive antenna(s) shall be directional panel or horn type antennas.

– 8 – IEC 62037-8:2025 © IEC 2025
5.1.3 Antenna directivity
The transmit and receive antenna directivity shall be 10,25 dBi ± 3,0 dBi at the f , f and IM
1 2
product test frequencies, where directivity, dir, is calculated as follows:
dir = 41 253 / (BW × BW )
A E
where
BW is the half power azimuth beam width of test antenna;
A
BW is the half power elevation beam width of test antenna.
E
5.1.4 Antenna VSWR
The transmit and receive antenna voltage standing wave ratio (VSWR) shall be less than 1,92:1
(10 dB return loss) at the f f and IM product test frequencies when measured in the test
1, 2
environment excluding the DUT and DUT support structure (if required).
5.1.5 Antenna polarization
The transmit and receive antennas shall be linearly polarized. If separate transmit and receive
antennas are used, the two antennas shall be co-polarized while measuring PIM.
5.1.6 DUT location
5.1.6.1 DUT distance from transmit antenna
5.1.6.1.1 General
Radiated PIM tests can be conducted in either the near field or the far field region of the test
system transmit antenna. Distance is defined as the shortest direct path between the front face
of the transmit antenna and the closest point on the DUT. The following test distance ranges
shall be used for far field and near field tests.
5.1.6.1.2 Far field test
The far field test distance range, TD , is calculated as follows:
ff
TD = 2 × D /λ ± 0,25 × λ
ff
where
λ is the wavelength of the lowest f or f test frequency;
1 2
D is the largest linear dimension of the transmit antenna.
5.1.6.1.3 Near field test
The near field test distance range, TD , is calculated as follows:
nf
TD = 1 × λ ± 0,1 × λ
nf
where
λ is the wavelength of the lowest f or f test frequency.
1 2
5.1.6.2 DUT location within the antenna beam
The centre of the DUT will be positioned at the centre of the transmit antenna's main beam with
no part of the DUT extending outside of the transmit antenna's half-power azimuth or elevation
beam widths, as shown in Figure 4. If the DUT is too large to meet this requirement, it is
acceptable to move the DUT and repeat the test until all areas of the DUT have been exposed
to the required level of RF energy. It is acceptable to move the DUT while PIM testing to meet
this requirement if human safety is not at risk.
, is calculated as follows:
Maximum test zone width, w
tz,max
w = D + 2 × S × Tan (BW / 2)
tz,max MIN A
where
D is the test antenna width or height, whichever is smaller;
MIN
S is the separation between antenna and DUT;
BW is the half power azimuth beam width of test antenna.
A
Maximum test zone height, h , is calculated as follows:
tz,max
h = D + 2 × S × Tan (BW / 2)
tz,max MIN E
where
D is the test antenna width or height, whichever is smaller;
MIN
S is the separation between antenna and DUT;
BW is the half power elevation beam width of test antenna.
E
Figure 4 – Test zone definition
5.1.7 DUT orientation
During the radiated PIM test the device or object shall be positioned in front of the test antenna
in an orientation that simulates how the device or object would normally be oriented in the field.

– 10 – IEC 62037-8:2025 © IEC
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