IEC TR 61292-12:2022

IEC TR 61292-12 ®
Edition 1.0 2022-09
TECHNICAL
REPORT
colour
inside
Optical amplifiers –
Part 12: Fibre amplifiers for space division multiplexing transmission

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IEC TR 61292-12 ®
Edition 1.0 2022-09
TECHNICAL
REPORT
colour
inside
Optical amplifiers –
Part 12: Fibre amplifiers for space division multiplexing transmission

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 33.180.30, 33.180.10 ISBN 978-2-8322-5755-5

– 2 – IEC TR 61292-12:2022  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 Classification of SDM OFAs . 9
5 Multi-core OFA technology . 10
5.1 Outline of multi-core EDFAs . 10
5.2 State-of-the-art multi-core EDFA development technology . 12
5.2.1 Core pumped multi-core EDFA . 12
5.2.2 Cladding pumped multi-core EDFA . 16
5.2.3 Core and cladding hybrid pumped MC-EDFA . 18
5.3 State-of-the-art remotely pumped MC-EDFA and MC-FRA technologies. 18
5.4 Specific features and measurements. 19
6 Few-mode OFA technology . 21
6.1 Outline of few-mode EDFA . 21
6.2 State-of-the-art few-mode EDFA development technology. 22
6.2.1 Few-LP mode EDFA . 22
6.2.2 OAM mode EDFA and Coupled-core mode EDFA . 25
6.3 State-of-the-art FM-FRA development technology . 26
6.4 Specific feature and measurement . 27
7 Combined MC and FM-OFA technology . 28
Bibliography . 30

Figure 1 – Classification of SDM OFAs . 10
Figure 2 – Concept of an MC-EDFA . 11
Figure 3 – Amplification media and pump methods for MC-EDFAs . 11
Figure 4 – Configurations of core-pumped MC-EDFAs . 13
Figure 5 – Configuration and amplification characteristics of a core-pumped MC-EDFA
with 7-core MC-EDF and conventional WDM couplers . 14
Figure 6 – Configuration and amplification characteristics of a core-pumped MC-EDFA
with 19-core MC-EDF and MC WDM coupler . 15
Figure 7 – Configuration of a cladding-pumped MC-EDFA . 16
Figure 8 – Pump light combiner . 17
Figure 9 – Configuration and amplification characteristics of an EDFA with 32-core
cladding pumped MC-EDF . 17
Figure 10 – Configuration of core and cladding hybrid-pumped MC-EDFA . 18
Figure 11 – Configuration and performance of remotely pumped MC-EDFA and
MC-FRA . 19
Figure 12 – Multi-core EDFA evaluation setup for basic optical characteristics . 20
Figure 13 – XT evaluation methods with different wavelengths . 20
Figure 14 – Image of each mode propagating through the core . 22
Figure 15 – Configuration of an FM-EDFA. 22

Figure 16 – Example of gain and NF of a 2-LP FM-EDFA (large core, step core index
and step erbium doping profile structured as in a conventional EDF) . 23
Figure 17 – Configuration and amplification characteristics of a 2-LP mode EDFA

prototype consisting of a ring-core FM-EDF, FM WDM coupler, and two FM isolators . 24
Figure 18 – Configuration and amplification characteristics of a 3-mode EDFA
prototype using 2-LP signal modes employing a ring-core FM-EDF . 25
Figure 19 – Configuration and amplification characteristics of a 2-OAM mode EDFA . 26
Figure 20 – 2-LP-mode FM-FRA experiment . 27
Figure 21 – FM-EDFA evaluation setup for basic optical characteristics . 28
Figure 22 – MC-EDFA with FM cores . 29

– 4 – IEC TR 61292-12:2022  IEC 2022
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
OPTICAL AMPLIFIERS –
Part 12: Fibre amplifiers for space
division multiplexing transmission

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
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rights. IEC shall not be held responsible for identifying any or all such patent rights.
IEC TR 61292-12 has been prepared by subcommittee 86C: Fibre optic systems and active
devices, of IEC technical committee 86: Fibre optics. It is a Technical Report.
External document OITDA/TP 33/AM [1] has served as a basis for the elaboration of this
document.
___________
Numbers in square brackets refer to the Bibliography.

The text of this Technical Report is based on the following documents:
Draft Report on voting
86C/1807/DTR 86C/1819/RVDTR
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 Technical Report 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/standardsdev/publications.
A list of all parts in the IEC 61292 series, published under the general title Optical amplifiers,
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,
• replaced by a revised edition, or
• amended.
IMPORTANT – The "colour inside" logo on the cover page of this document indicates that it
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contents. Users should therefore print this document using a colour printer.

– 6 – IEC TR 61292-12:2022  IEC 2022
INTRODUCTION
Optical amplifiers (OAs) are essential components for designing long-haul optical transmission
systems, for which many standards ha
...