IEC 60027-2:2019

IEC 60027-2 ®
Edition 4.0 2019-01
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Letter symbols to be used in electrical technology –
Part 2: Telecommunications and electronics

Symboles littéraux à utiliser en électrotechnique –
Partie 2: Télécommunications et électronique

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IEC 60027-2 ®
Edition 4.0 2019-01
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Letter symbols to be used in electrical technology –

Part 2: Telecommunications and electronics

Symboles littéraux à utiliser en électrotechnique –

Partie 2: Télécommunications et électronique

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 01.060; 33.020 ISBN 978-2-8322-6346-4

– 2 – IEC 60027-2:2019 © IEC 2019
CONTENTS
FOREWORD . 3
1 Scope . 5
2 Normative references . 5
3 Terms and definitions . 5
4 Introduction to tables . 5
5 Quantities and units . 6
5.1 General concepts . 6
5.2 Linear time-independent networks under sinusoidal conditions . 20
5.2.1 General . 20
5.2.2 Two-port networks . 20
5.2.3 n-port networks . 28
5.3 Line transmission of signals and telephony . 34
5.3.1 Quantities and units in line transmission . 34
5.3.2 Subscripts for line transmission . 35
5.3.3 Quantities and units in telephony . 36
5.3.4 Subscripts for telephony . 36
5.4 Waveguide propagation . 37
5.4.1 Frequency and wavelength in a waveguide . 37
5.4.2 Characteristic and normalized impedance and admittance in general. 38
5.4.3 Impedance and admittance at a point in a substance . 39
5.4.4 Impedance and admittance at a point in vacuum . 40
5.4.5 Impedance and admittance of a waveguide . 41
5.5 Radiocommunications . 42
5.5.1 General and tropospheric propagation . 42
5.5.2 Ionospheric propagation . 45
5.5.3 Antennas . 46
5.5.4 Radio links. 51
5.6 Optical fibre communication . 53
5.7 Television . 59
5.8 Dependability . 61
5.9 Piezoelectric resonators . 62
5.10 Semiconductor devices . 68
5.11 Electroacoustics . 68
Bibliography . 73

Figure 1 – Conventions concerning signs in electric circuits . 20
Figure 2 – Conventions for n-port linear networks . 28
Figure 3 – Equivalent circuits of a one-port piezoelectric resonator . 62

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
LETTER SYMBOLS TO BE USED IN ELECTRICAL TECHNOLOGY –

Part 2: Telecommunications and electronics

FOREWORD
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International Standard IEC 60027-2 has been prepared by IEC technical committee 25:
Quantities and units.
This fourth edition cancels and replaces the third edition published in 2005. This fourth edition
constitutes a technical revision.
This edition includes the following significant changes with respect to the previous edition:
a) former Subclauses 3.8 and 3.9 are cancelled and replaced by IEC 80000-13:2008;
b) former Subclause 3.10, now 4.8, is revised in accordance with IEC 60050-192:2015;
c) former Subclause 3.11, now 4.9, is revised in accordance with IEC 60050-561:2014;
d) former Subclause 3.13, now 4.11, is revised in accordance with ISO 80000-8:2007,
IEC 60050-801:1994 and IEC 60050-802:2011;
e) technical and editorial corrections have been carried out, mainly in Subclause 4.1.
f) tables are simplified, mainly by deleting useless columns.

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