IEC 63098-2:2022

IEC 63098-2 ®
Edition 1.0 2022-12
INTERNATIONAL
STANDARD
colour
inside
Transmitting and receiving equipment for radiocommunication – Radio-over-
fibre technologies and their performance standard –
Part 2: Radio-over-fibre-based fronthaul network for railway communication
systems
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IEC 63098-2 ®
Edition 1.0 2022-12
INTERNATIONAL
STANDARD
colour
inside
Transmitting and receiving equipment for radiocommunication – Radio-over-

fibre technologies and their performance standard –

Part 2: Radio-over-fibre-based fronthaul network for railway communication

systems
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 33.060.20 ISBN 978-2-8322-6056-2

– 2 – IEC 63098-2:2022  IEC 2022
CONTENTS
FOREWORD . 4
INTRODUCTION . 6
1 Scope . 7
2 Normative references . 7
3 Terms, definitions and abbreviated terms . 7
3.1 Terms and definitions . 7
3.2 Abbreviated terms . 8
4 Functional specification . 8
4.1 RoF fronthaul network . 8
4.2 RoF transmitter and receiver . 9
4.3 Operating environment . 9
5 Testing . 9
5.1 General . 9
5.2 Performance testing . 9
6 Environmental specifications . 9
6.1 General safety . 9
6.2 Laser safety . 10
6.3 Temperature and environment . 10
Annex A (normative) Specifications for RoF fronthaul networks in railway
communication systems . 11
A.1 Overview. 11
A.2 Diagrams . 12
A.2.1 Optical switch-based system . 12
A.2.2 WDM-based system . 12
A.3 Functional specification. 13
A.4 Testing . 14
A.4.1 General . 14
A.4.2 Performance testing. 14
Annex B (informative) Specifications for the DSB RoF transmitter for fronthaul
systems in railway communication systems . 15
B.1 Overview. 15
B.2 Diagrams . 16
B.3 Functional specification. 17
B.4 Testing . 17
B.4.1 General . 17
B.4.2 Characterization testing . 17
B.4.3 Performance testing. 17
Annex C (informative) Specifications for SSB RoF transmitter for fronthaul system in
railway communication systems . 18
C.1 Overview. 18
C.2 Diagrams . 18
C.3 Functional specification. 19
C.4 Testing . 19
C.4.1 General . 19
C.4.2 Characterization testing . 19
C.4.3 Performance testing. 19

Bibliography . 20

Figure 1 – Block diagram of RoF fronthaul network for a railway communication system . 9
Figure A.1 – Schematic diagram of a railway communication system . 11
Figure A.2 – Block diagram of optical-switch-based fronthaul network . 12
Figure A.3 – Block diagram of WDM-based fronthaul network . 13
Figure B.1 – Relative RF throughput of the DSB-modulated signals over some length of
the optical fibre at a centre frequency of 3 GHz and 15 GHz . 16
Figure B.2 – Block diagram of DSB RoF transmitter with (a) external modulation and

(b) direct modulation systems . 16
Figure B.3 – Block diagram of DSB RoF transmitter with (a) external modulation and
(b) direct modulation systems for the WDM-based network . 17
Figure C.1 – Block diagram of SSB RoF transmitter with (a) DSB E/O with an optical
filter, (b) DD-MZM-based system and (c) IQ-modulator-based systems . 18

Table 1 – Abbreviated terms . 8
Table 2 – Operating environment . 9
Table A.1 – Functional specification of the RoF fronthaul network . 14
Table A.2 – Performance test plan . 14
Table B.1 – Functional specification of DSB RoF transmitter . 17
Table C.1 – Functional specification of SSB RoF transmitter . 19

– 4 – IEC 63098-2:2022  IEC 2022
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
TRANSMITTING AND RECEIVING EQUIPMENT FOR
RADIOCOMMUNICATION – RADIO-OVER-FIBRE
TECHNOLOGIES AND THEIR PERFORMANCE STANDARD –

Part 2: Radio-over-fibre-based fronthaul network
for railway communication systems

FOREWORD
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IEC 63098-2
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