IEC 61097-4:2007

IEC 61097-4
Edition 2.0 2007-10
INTERNATIONAL
STANDARD
Global maritime distress and safety system (GMDSS) –
Part 4: INMARSAT-C ship earth station and INMARSAT enhanced group call
(EGC) equipment – Operational and performance requirements, methods of
testing and required test results

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IEC 61097-4
Edition 2.0 2007-10
INTERNATIONAL
STANDARD
Global maritime distress and safety system (GMDSS) –
Part 4: INMARSAT-C ship earth station and INMARSAT enhanced group call
(EGC) equipment – Operational and performance requirements, methods of
testing and required test results

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
PRICE CODE
U
ICS 47.020.70 ISBN 2-8318-9317-8

– 2 – 61097-4 © IEC:2007(E)
CONTENTS
FOREWORD.4

1 Scope.6
2 Normative references .6
3 Performance requirements .7
3.1 Introduction .7
3.2 Non-operational requirements common to all classes of INMARSAT-C SES
and INMARSAT-EGC .7
3.3 Operational requirements for all classes of INMARSAT-C SES including
those with INMARSAT-EGC .8
3.4 Operational requirements for INMARSAT-EGC receivers including those
incorporated in an INMARSAT-C SES .9
3.5 Performance related requirements from IEC 60945 .10
3.6 Other requirements additional to those of volume 3 of the INMARSAT-C SDM .11
4 Technical characteristics .11
4.1 Introduction .11
4.2 Environmental and electromagnetic compatibility requirement .11
4.3 Radiated spurious emissions .12
5 Methods of testing and required test results .16
5.1 Introduction .16
5.2 Tests of non-operational requirements for all classes of INMARSAT-C SES
and INMARSAT-EGC .17
5.3 Tests of operational requirements for all classes of INMARSAT-C SES
(including those with INMARSAT-EGC) .17
5.4 Tests of operational requirements for INMARSAT-EGC receivers (including
those incorporated in an INMARSAT-C SES).17
5.5 Tests of performance related requirements from IEC 60945 .18
5.6 Tests of other requirements additional to those of the INMARSAT-C SDM.19
5.7 Tests of technical characteristics.19

Annex A (normative) Requirements relating to installation .23
Annex B (normative) Radiated unwanted emissions .24

Table 1 – INMARSAT-C SES technical characteristics .12
Table 2 – INMARSAT-EGC technical characteristics .14
Table 3 – Environmental conditions for INMARSAT-C SESs and INMARSAT-EGC

equipment suitable for GMDSS use .16
Table 4 – INMARSAT-C SES schedule of tests .20
Table 5 – INMARSAT-EGC schedule of tests .22
Table B.1 – Limits of unwanted emissions up to 1 000 MHz at a measuring distance of
10 m .24
Table B.2 – Limits of unwanted emissions above 1 000 MHz and outside the bands
1 626,5 MHz to 1 645,5 MHz and 1 656,6 MHz to 1 660,5 MHz applicable before
1 June 2002.24
Table B.3 – Limits of unwanted emissions above 1 000 MHz and outside the bands
1 626,5 MHz to 1 645,5 MHz and 1 656,6 MHz to 1 660,5 MHz applicable from 1 June
2002 .26

61097-4 © IEC:2007(E) – 3 –
Table B.4 – Limits of unwanted emission within the operating band with carrier-on .27

– 4 – 61097-4 © IEC:2007(E)
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
GLOBAL MARITIME DISTRESS AND
SAFETY SYSTEM (GMDSS) –
Part 4: INMARSAT-C ship earth station and
INMARSAT enhanced group call (EGC) equipment –
Operational and performance requirements,
methods of testing and required test results

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
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patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 61097-4 has been prepared by IEC technical committee 80:
Maritime navigation and radiocommunication equipment and systems.
This second edition cancels and replaces the first edition published in 1994. This edition
constitutes a technical revision.
The main changes with respect to the previous edition are:
– the IMO references and requirements have been updated to the new performance
standards for Inmarsat-C ship earth stations adopted in 1995;
– the requirements for interfaces have been updated to the current version of IEC 61162-1;
– the general requirements have been updated to the current version of IEC 60945;

61097-4 © IEC:2007(E) – 5 –
– Annex B concerning radiated unwanted emissions has been updated to current
requirements.
The text of this standard is based on the following documents:
FDIS Report on voting
80/487/FDIS 80/497/RVD
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all parts of IEC 61097 series, published under the general title Global maritime
distress and safety system (GMDSS), can be found on the IEC website.
The committee has decided that the contents of this publication will remain unchanged until
the maintenance result 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.

– 6 – 61097-4 © IEC:2007(E)
GLOBAL MARITIME DISTRESS AND
SAFETY SYSTEM (GMDSS) –
Part 4: INMARSAT-C ship earth station and
INMARSAT enhanced group call (EGC) equipment –
Operational and performance requirements,
methods of testing and required test results

1 Scope
This part of IEC 61097 specifies the performance requirements and methods of testing for
INMARSAT-C ship earth stations (SES) capable of transmitting and receiving direct-printing
communications, and for enhanced group call (EGC) equipment, for use in the GMDSS. The
available variants are:
Class 0: An EGC receiver, either stand-alone or an element of a GMDSS installation in
accordance with the INMARSAT design and installation guidelines (DIGs) for
GMDSS installations.
Class 1: A basic SES providing shore-to-ship and ship-to-shore message transfer only.
Class 2: As class 1 but with EGC as an alternative to shore-to-ship transfer using a
shared receiver.
Class 3: As class 1 but with EGC using an independent receiver.
The standard complies with IMO performance requirements stated in the normative
references, INMARSAT technical characteristics and test procedures, and IEC 60945 general
requirements except where modifications are explicitly stated in this standard. Technical
characteristics essential to GMDSS operation as defined by the IMO are identified.
All text of this standard, whose wording is identical to that in IMO SOLAS Convention 1974 as
amended in 1988 and Resolutions A.807(19), A.664(16), and A.694(17) is printed in italics
and reference made to the Resolution/Recommendation and subclause number.
This standard covers equipment construction and testing. Matters relatin
...