IEC TR 61156-1-5:2013

Multicore and symmetrical pair/quad cables for digital communications - Part 1-5: Correction procedures for the measurement results of return loss and input impedance

IEC/TR 61156-1-5:2013(E), which is a Technical Report, describes correction procedures for the measurement results of return loss and input impedance.

General Information

• Status: Published
• Publication Date: 24-Jun-2013
• ICS: 01 - GENERALITIES. TERMINOLOGY. STANDARDIZATION. DOCUMENTATION
• ICS: 03.120.01 - Quality in general
• ICS: 19.020 - Test conditions and procedures in general
• ICS: 21.020 - Characteristics and design of machines, apparatus, equipment
• ICS: 33.120.20 - Wires and symmetrical cables
• Technical Committee: SC 46C - Wires and symmetric cables
• Current Stage: PPUB - Publication issued
• Start Date: 15-Oct-2013
• Completion Date: 25-Jun-2013

Standards Content (Sample)

IEC/TR 61156-1-5 ®
Edition 1.0 2013-06
TECHNICAL
REPORT
colour
inside
Multicore and symmetrical pair/quad cables for digital communications –
Part 1-5: Correction procedures for the measurement results of return loss and
input impedance
IEC/TR 61156-1-5:2013(E)
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IEC/TR 61156-1-5 ®
Edition 1.0 2013-06
TECHNICAL
REPORT
colour
inside
Multicore and symmetrical pair/quad cables for digital communications –

Part 1-5: Correction procedures for the measurement results of return loss and

input impedance
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
PRICE CODE
S
ICS 33.120.20 ISBN 978-2-83220-918-9

– 2 – TR 61156-1-5  IEC:2013(E)
CONTENTS
FOREWORD . 3
1 Scope . 5
2 Normative references . 5
3 Acronyms . 5
4 Return loss measurements . 6
4.1 General . 6
4.2 Return loss (RL) . 6
4.3 Open/short return loss (OSRL) . 7
4.4 Structural return loss (SRL) . 7
5 Correction procedures . 8
5.1 General . 8
5.2 Parasitic inductance corrected return loss (PRL) . 9
5.3 Gated return loss (GRL) . 10
5.4 Fitted return loss (FRL) . 12
Annex A (informative) Comparison of gated return loss (GRL) with fitted return loss (FRL) . 18
Annex B (informative) Influence of the correction technique on return loss peaks . 20

Figure 1 – Return loss with and without junction reflections . 6
Figure 2 – Return loss and open/short return loss . 7
Figure 3 – Return loss, open short return loss and structural return loss . 8
Figure 4 – Input impedance (magnitude) and operational return loss up to 2 GHz . 9
Figure 5 – Equivalent circuit for the corrective calculation . 9
Figure 6 – Return loss with gating correction . 12
Figure 7 – Return loss and input impedance before any correction . 15
Figure 8 – Return loss and input impedance (with fitting) after fixture correction . 15
Figure 9 – Residual impedance (after fixture correction) and its fitting . 16
Figure 10 – Return loss and input impedance after complete correction . 16
Figure 11 – Return loss, with fixture correction vs. without fixture correction . 17
Figure 12 – Input impedance (real and imaginary part), with fixture correction vs. without
fixture correction . 17
Figure A.1 – Return loss, fitting vs. gating correction . 18
Figure A.2 – Real part of input impedance, fitting vs. gating correction . 18
Figure A.3 – Imaginary part of input impedance, fitting vs. gating correction . 19
Figure B.1 – Reflection coefficient of a Cat.6 data cable in polar coordinates without and
with PRL-correction . 20
Figure B.2 – Return loss traces corresponding to Figure B.1 . 20
Figure B.3 – Reflection coefficient of a Cat.6 data cable in polar coordinates without and
with PRL-correction . 21
Figure B.4 – Return loss traces corresponding to Figure B.3 . 21

TR 61156-1-5  IEC:2013(E) – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
MULTICORE AND SYMMETRICAL PAIR/QUAD
CABLES FOR DIGITAL COMMUNICATIONS –

Part 1-5: Correction procedures for the measurement
results of return loss and input impedance

FOREWORD
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The main task of IEC technical committees is to prepare International Standards. However, a
technical committee may propose the publication of a technical report when it has collected data
of a different kind from that which is normally published as an International Standard, for
example "state of the art".
IEC/TR 61156-1-5, which is a technical report, has been prepared by subcommittee SC46C:
Wires and symmetric cables, of IEC technical committee TC46: Cables, wires, waveguides, R.F.
connectors, R.F. and microwave passive components and accessories.
The text of this technical report is based on the following documents:
Enquiry draft Report on voting
46C/973/DTR 46C/979/RVC
Full information on the voting for the approval of this technical report can be found in the report
on voting indicated in the above table.

– 4 – TR 61156-1-5  IEC:2013(E)
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all parts in the IEC 61156 series, published under the general title Multicore and
symmetrical pair/quad cables for digital communications, can be found on the IEC website.
The committee has decided that the contents of this publication will remain unchanged until the
stability date indicated on the IEC web site under "http://webstore.iec.ch" in the data related to
the specific publication. At this date, the publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
A bilingual version of this publication may be issued at a later date.

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TR 61156-1-5  IEC:2013(E) – 5 –
MULTICORE AND SYMMETRICAL PAIR/QUAD
CABLES FOR DIGITAL COMMUNICATIONS –

Part 1-5: Correction procedures for the measurement
results of return loss and input impedance

1 Scope
This part of IEC 61156 describes correction procedures for the measurement results of return
loss and input impedance.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and
are indispensable for its application. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments)
applies.
IEC 61156-1, Multicore and symmetrical pair/quad cables for digital communications – Part 1:
Generic specification
IEC/TR 61156-1-2, Multicore and symmetrical pair/quad cables for digital communications –
Part 1-2: Electrical transmission characteristics and test methods of symmetrical pair/quad
cables
IEC/TR 62152, Transmission properties of cascaded two-ports or quadripols – Background of
terms and definitions
IEC 62153-1-1, Metallic communication cables test methods – Part 1-1: Electrical –
Measurement of the pulse/step return loss in the frequency domain using the Inverse Discrete
Fourier Transformation
ASTM D4566:1998, Standard Test Methods for Electrical Performance Properties of Insulations
and Jackets for Telecommunications Wire and Cable
3 Acronyms
CUT cable under test
FRL fitted return loss
GRL gated return loss
IFDT Inverse discrete Fourier transformation
OSRL open short return loss
PRL
parasitic inductance corrected return loss
RL return lo
...