IEC 62287-2:2013

Maritime navigation and radiocommunication equipment and systems - Class B shipborne equipment of the automatic identification system (AIS) - Part 2: Self-organising time division multiple access (SOTDMA) techniques

IEC 62287-2:2013 specifies operational and performance requirements, methods of testing and required test results for Class B "SO" shipborne AIS equipment using Self-organised TDMA (SOTDMA) techniques as described in Recommendation ITU-R M.1371. This standard takes into account other associated IEC International Standards and existing national standards, as applicable. The main differences between Class B "CS" (IEC 62287-1) and Class B "SO" units are that the Class B "SO":
- covers all 25 kHz channels listed in Recommendation ITU-R M.1084-5;
- only uses the internal GNSS, no position sensor input is allowed;
- requires use of VDL Message 17 for correction of the internal GNSS;
- has a presentation interface;
- has additional reporting intervals, down to 5 s;
- has two power settings, with a high level of 5 W;
- has the capability to transmit binary messages. It is applicable for AIS equipment used on craft that are not covered by a mandatory carriage requirement of AIS under SOLAS Chapter V.

Matériels et systèmes de navigation et de radiocommunication maritimes - Transpondeur embarqué du Système d'Identification Automatique (AIS) de classe B - Partie 2: Techniques auto-organisées d'accès multiple par répartition dans le temps (SOTDMA)

L'IEC 62287-2:2013 spécifie les exigences opérationnelles et de performance, les méthodes d'essai et les résultats d'essai exigibles pour le transpondeur embarqué du système d'identification automatique (AIS) de classe B "SO" utilisant les techniques auto-organisées TDMA (SOTDMA) telles qu'elles sont décrites dans la Recommandation UIT-R M.1371. La présente Norme prend en compte d'autres normes internationales IEC associées et des normes nationales existantes, selon le cas.
Les différences principales entre les unités de la classe B "CS" (IEC 62287-1) et de la classe B "SO" sont le fait que la classe B "SO":
- couvre tous les voies de 25 kHz énumérées dans la Recommandation UIT-R M.1084-5;
- n'utilise que le système mondial de navigation par satellite (GNSS) interne, aucune entrée provenant d'un capteur de position n’est autorisée;
- nécessite l'utilisation du message 17 sur une liaison de données en ondes métriques (VDL) pour la correction du GNSS interne;
- a une interface de présentation;
- a des intervalles de rapport supplémentaires, jusqu'à 5 s;
- a deux réglages de puissance, avec un niveau supérieur de 5 W;
- a la capacité de transmettre des messages binaires.
Elle est applicable aux équipements AIS utilisés sur le navire, qui ne sont pas visés par l'exigence relative aux AIS de bord obligatoires selon le Chapitre V de la SOLAS.

General Information

• Status: Published
• Publication Date: 17-Mar-2013
• ICS: 47.020.70 - Navigation and control equipment
• Technical Committee: TC 80 - Maritime navigation and radiocommunication equipment and systems
• Drafting Committee: WG 15 - TC 80/WG 15
• Current Stage: DELPUB - Deleted Publication
• Start Date: 07-Feb-2017
• Completion Date: 26-Oct-2025

Relations

• Revised: IEC 62287-2:2017 - Maritime navigation and radiocommunication equipment and systems - Class B shipborne equiment of the automatic identification system (AIS) - Part 2: Self-organising time division multiple access (SOTDMA) techniques
• Effective Date: 05-Sep-2023

Overview

IEC 62287-2:2013 specifies operational and performance requirements, test methods and required test results for Class B "SO" shipborne AIS equipment using Self‑Organising Time Division Multiple Access (SOTDMA) techniques. Aligned with Recommendation ITU‑R M.1371, this IEC standard applies to AIS units intended for craft not subject to mandatory SOLAS carriage under SOLAS Chapter V. It defines functionality, environmental and EMC requirements, link and network layer behavior, and laboratory and operational test procedures for Class B “SO” devices.

Key technical topics and requirements

• Scope and capabilities: Covers Class B “SO” AIS using SOTDMA (self‑organising TDMA) and the full set of 25 kHz channels listed in ITU‑R M.1084‑5.
• Positioning: Requires an internal GNSS receiver only; external position sensor input is not permitted.
• GNSS correction: Mandates use of VDL Message 17 for correction of the internal GNSS.
• Reporting and messaging:
  • Additional reporting intervals, down to 5 s for dynamic reports.
  • Capability to transmit binary messages (data messaging).
  • Presentation interface for local display and message presentation.
• Power and RF: Two transmitter power settings are defined with a high level of 5 W. Physical layer, transmitter/receiver performance, spurious emissions and modulation accuracy are covered in detail.
• Functional and safety tests: Operational tests (autonomous, single message, polled/interrogation modes), built‑in integrity tests (BIIT), alarms, fallback arrangements and transmitter shutdown procedures.
• Conformance testing: Environmental, EMC, vibration, shock, and a comprehensive set of laboratory measurements for TDMA transmitters and receivers, link layer behavior, multi‑channel operation and synchronisation.

Practical applications - who uses this standard

• Marine electronics manufacturers designing and producing Class B “SO” AIS transceivers.
• Test laboratories and certification bodies performing compliance and type‑approval testing.
• Marine integrators and system installers specifying AIS for recreational craft, yachts and non‑SOLAS vessels.
• Naval architects, yacht builders and procurement teams seeking compliant AIS equipment.
• Regulators and port authorities referencing technical requirements for non‑SOLAS AIS usage.

Related standards and references

• IEC 62287‑1 (Class B “CS” specifications) - for comparison of Class B variants.
• ITU‑R M.1371 - AIS protocol and SOTDMA techniques.
• ITU‑R M.1084‑5 - channel plan (25 kHz channels).
• SOLAS Chapter V - carriage requirements for AIS applicability.

IEC 62287‑2:2013 is essential for ensuring reliable, interoperable AIS SOTDMA implementations on non‑SOLAS craft, guiding manufacturers, testers and users through technical, safety and conformance requirements.

Standards Content (Sample)

IEC 62287-2 ®
Edition 1.0 2013-03
INTERNATIONAL
STANDARD
colour
inside
Maritime navigation and radiocommunication equipment and systems – Class B
shipborne equipment of the automatic identification system (AIS) –
Part 2: Self-organising time division multiple access (SOTDMA) techniques

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IEC 62287-2 ®
Edition 1.0 2013-03
INTERNATIONAL
STANDARD
colour
inside
Maritime navigation and radiocommunication equipment and systems – Class B

shipborne equipment of the automatic identification system (AIS) –

Part 2: Self-organising time division multiple access (SOTDMA) techniques

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
PRICE CODE
XC
ICS 47.020.70 ISBN 978-2-83220-682-9

– 2 – 62287-2 © IEC:2013(E)
CONTENTS
FOREWORD . 7
1 Scope . 9
2 Normative references . 9
3 Abbreviations . 10
4 General requirements . 11
4.1 General . 11
4.1.1 Capabilities of the Class B “SO” AIS . 11
4.1.2 Quality assurance . 11
4.1.3 Safety of operation . 11
4.1.4 Additional features . 12
4.1.5 Functionality . 12
4.2 Manuals . 12
4.3 Marking and identification . 12
5 Environmental, power supply, interference and safety requirements . 12
6 Performance requirements . 13
6.1 Internal processes . 13
6.2 Operating frequency channels . 14
6.3 Internal GNSS receiver for position reporting. 14
6.4 Identification . 14
6.5 AIS Information . 14
6.5.1 Information content . 14
6.5.2 Information reporting intervals . 15
6.5.3 Short safety-related messages . 16
6.5.4 Permissible initialisation period . 16
6.6 Alarms and indications, fall-back arrangements . 16
6.6.1 Built-in integrity tests (BIIT) . 16
6.6.2 Transmitter shutdown procedure . 17
6.6.3 Position sensor fallback conditions . 18
6.7 User interface . 18
6.7.1 Indication and display . 18
6.7.2 Static data input . 19
6.7.3 External interfaces . 19
6.8 Protection from invalid control commands . 19
7 Technical requirements . 19
7.1 General . 19
7.2 Physical layer . 20
7.2.1 General . 20
7.2.2 Receiver characteristics . 20
7.2.3 Other characteristics . 21
7.2.4 Transmitter requirements . 22
7.3 Link layer . 23
7.3.1 General . 23
7.3.2 Link sub-layer 1: Medium Access Control (MAC) . 23
7.3.3 Link sub-layer 2: Data Link Service (DLS). 25
7.3.4 Link sub-layer 3: Link Management Entity (LME) . 25
7.4 Network layer . 29

62287-2 © IEC:2013(E) – 3 –
7.4.1 General . 29
7.4.2 Management of regional operating settings. 29
7.4.3 Multi-channel operation . 30
7.5 Transport layer . 30
7.6 Presentation Interface . 31
7.7 DSC receive capability . 31
8 Test conditions . 31
8.1 General . 31
8.2 Normal test conditions . 31
8.2.1 Temperature and humidity . 31
8.2.2 Power supply . 31
8.3 Extreme test conditions . 31
8.4 Test signals . 31
8.4.1 Standard test signal number 1 . 31
8.4.2 Standard test signal number 2 . 32
8.4.3 Standard test signal number 3 . 32
8.4.4 Standard test signal number 4 . 32
8.5 Standard test environment . 33
8.5.1 Test setup . 33
8.5.2 Sensor test input . 33
8.5.3 Synchronisation . 33
8.5.4 Test signals applied to the receiver input . 33
8.5.5 Waiver for receivers . 34
8.5.6 Artificial antenna (dummy load) . 34
8.5.7 Modes of operation of the transmitter . 34
8.5.8 Common test conditions for protection from invalid controls . 34
8.5.9 Measurement uncertainties . 34
9 Power supply, environmental and EMC tests . 35
9.1 Test summary. 35
9.2 Vibration . 36
9.2.1 Purpose . 36
9.2.2 Method of measurement . 36
9.2.3 Required results . 36
9.3 Shock . 36
9.3.1 Purpose . 36
9.3.2 Method of measurement . 36
9.3.3 Required result . 36
9.4 Performance tests / checks . 36
9.5 Under voltage test (brown out) . 37
9.5.1 Purpose . 37
9.5.2 Method of test . 37
9.5.3 Required result . 37
9.6 Under voltage test (short term) . 37
9.6.1 Purpose . 37
9.6.2 Method of test . 37
9.6.3 Required result . 37
10 Operational tests . 37
10.1 General . 37
10.1.1 Tests by inspection . 37

– 4 – 62287-2 © IEC:2013(E)
10.1.2 Safety of operation . 38
10.1.3 Additional features . 38
10.2 Modes of operation . 38
10.2.1 Autonomous mode . 38
10.2.2 Single messages . 40
10.2.3 Polled mode / Interrogation response . 43
10.3 Channel selection . 44
10.3.1 Valid channels . 44
10.3.2 Invalid channels. 44
10.4 Internal GNSS receiver . 44
10.5 AIS information. 45
10.5.1 Information content . 45
10.5.2 Information update intervals . 45
10.6 Initialisation period . 47
10.6.1 Purpose . 47
10.6.2 Method of measurement . 47
10.6.3 Required results . 47
10.7 Alarms and indications, fall-back arrangements . 47
10.7.1 Built in integrity test . 47
10.7.2 Transceiver protection . 48
10.7.3 Transmitter shutdown procedure . 48
10.7.4 Position sensor fallback conditions . 48
10.8 User interface . 49
10.8.1 Status indication . 49
10.8.2 Message display . 49
10.8.3 Static data input . 50
11 Physical tests . 51
11.1 TDMA transmitter . 51
11.1.1 Frequency error . 51
11.1.2 Carrier power . 51
11.1.3 Transmission spectrum . 52
11.1.4 Modulation accuracy . 53
11.1.5 Transmitter output power versus time function . 54
11.2 TDMA receivers . 55
11.2.1 Sensitivity . 55
11.2.2 Error behaviour at high input levels . 56
11.2.3 Co-channel rejection . 56
11.2.4 Adjacent channel selectivity . 57
11.2.5 Spurious response rejection . 58
11.2.6 Intermodulation response rejection . 60
11.2.7 Blocking or desensitisation . 62
11.3 Conducted spurious emissions . 62
11.3.1 Spurious emissions from the receiver . 62
11.3.2 Spurious emissions from the transmitter . 63
12 Specific tests of Link layer . 63
12.1 TDMA synchronisation . 64
12.1.1 Synchronisation test using UTC direct and indirect . 64
12.1.2 Synchronisation test without UTC, EUT receiving semaphore . 64
12.2 Time division (frame format) . 65

62287-2 © IEC:2013(E) – 5 –
12.2.1 Purpose . 65
12.2.2 Method of measurement . 65
12.2.3 Required results . 65
12.3 Synchronisation jitter . 65
12.3.1 Definition . 65
12.3.2 Purpose . 65
12.3.3 Method of measurement . 65
12.3.4 Required results . 65
12.4 Data encoding (bit stuffing) . 65
12.4.1 Purpose . 65
12.4.2 Method of measurement . 65
12.4.3 Required results . 66
12.5 Frame check sequence . 66
12.5.1 Purpose . 66
12.5.2 Method of measurement . 66
12.5.3 Required results . 66
12.6 Slot allocation (Channel access protocols) . 66
12.6.1 Network entry . 66
12.6.2 Autonomous scheduled transmissions (SOTDMA) . 66
12.6.3 Autonomous scheduled transmissions (ITDMA) . 67
12.6.4 Transmission of Messages 24A and 24B (ITDMA) . 67
12.6.5 Assigned operation . 67
12.6.6 Group assignment . 69
12.6.7 Base station reservations . 73
12.7 Message formats . 74
12.7.1 Received messages. 74
12.7.2 Transmitted messages . 74
13 Specific tests of network layer . 74
13.1 Regional area designation by VDL Message . 74
13.1.1 Purpose . 74
13.1.2 Method of measurement . 74
13.1.3 Required results . 75
13.2 Channel management by addressed Message 22 . 76
13.2.1 Purpose . 76
13.2.2 Method of measurement . 76
13.2.3 Required results . 76
13.3 Invalid regional operating areas. 76
13.3.1 Purpose . 76
13.3.2 Method of measurement . 76
13.3.3 Required test results . 76
13.4 Continuation of autonomous mode reporting interval . 76
13.4.1 Purpose . 76
13.4.2 Method of test . 77
13.4.3 Required result . 77
13.5 Slot reuse and FATDMA reservations . 77
13.5.1 Method of measurement . 77
13.5.2 Required results . 77
13.6 Other features . 77
Annex A (normative) DSC channel management . 78

– 6 – 62287-2 © IEC:2013(E)
Annex B (normative) Calculation of area size . 86
Bibliography . 87

Figure 1 – OSI layer model . 20
Figure 2 – Power versus time mask . 24
Figure 3 – Format for repeating four-packet cluster . 32
Figure 4 – Measurement arrangement for carrier power . 51
Figure 5 – Emission mask . 53
Figure 6 – Measurement arrangement for modulation accuracy . 53
Figure 7 – Measurement arrangement . 55
Figure 8 – Measurement arrangement with two generators . 57
Figure 9 – SINAD or PER/BER measuring equipment . 59
Figure 10 – Measurement arrangement for intermodulation . 61
Figure 11 – Regional transitional zones . 75

Table 1 – Dynamic information autonomous reporting intervals for Class B “SO” AIS . 16
Table 2 – BIIT and reaction to malfunctions . 17
Table 3 – Position sensor fallback conditions . 18
Table 4 – Required receiver performance . 21
Table 5 – Transceiver characteristics . 21
Table 6 – Transmitter characteristics . 23
Table 7 – Definitions of timing for Figure 2 . 25
Table 8 – Use of VDL Messages by a Class B “SO” AIS . 28
Table 9 – Content of first two packets . 32
Table 10 – Fixed PRS data derived from Recommendation ITU-T O.153 . 33
Table 11 – Test . 35
Table 12 – Peak frequency deviation versus time. 54
Table 13 – Frequencies for intermodulation test . 61
Table 14 – Regional area scenario . 75
Table 15 – Required channels in use . 75
Table A.1 – DSC monitoring times . 79
Table B.1 – Coordinate points . 86

62287-2 © IEC:2013(E) – 7 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
MARITIME NAVIGATION AND RADIOCOMMUNICATION
EQUIPMENT AND SYSTEMS –
CLASS B SHIPBORNE EQUIPMENT OF
THE AUTOMATIC IDENTIFICATION SYSTEM (AIS) –

Part 2: Self-organising time division multiple access
(SOTDMA) techniques
FOREWORD
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International Standard IEC 62287-2 has been prepared by IEC technical committee 80:
Maritime navigation and radiocommunication equipment and systems.
The text of this standard is based on the following documents:
FDIS Report on voting
80/685/FDIS 80/691/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.

– 8 – 62287-2 © IEC:2013(E)
A list of all parts in the IEC 62287 series, published under the general title Maritime
navigation and radiocommunication and systems – Class B shipborne equipment of the
automatic identification system (AIS), 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.

IMPORTANT – The 'colour inside' logo on the cover page of this publication
indicates that it contains colours which are considered to be useful for the correct
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62287-2 © IEC:2013(E) – 9 –
MARITIME NAVIGATION AND RADIOCOMMUNICATION
EQUIPMENT AND SYSTEMS –
CLASS B SHIPBORNE EQUIPMENT OF
THE AUTOMATIC IDENTIFICATION SYSTEM (AIS) –

Part 2: Self-organising time division multiple access
(SOTDMA) techniques
1 Scope
This part of IEC 62287 specifies operational and performance requirements, methods of
testing and required test results for Class B “SO” shipborne AIS equipment using Self-
organised TDMA (SOTDMA) techniques as described in Recommendation ITU-R M.1371. This
standard takes into account other associated IEC International Standards and existing
national standards, as applicable.
The main differences between Class B “CS” (IEC 62287-1) and Class B “SO” units are that
the Class B “SO”:
• covers all 25 kHz channels listed in Recommendation ITU-R M.1084-5;
• only uses the internal GNSS, no position sensor input is allowed;
• requires use of VDL Message 17 for correction of the internal GNSS;
• has a presentation interface;
• has additional reporting intervals, down to 5 s;
• has two power settings, with a high level of 5 W;
• has the capability to transmit binary messages.
It is applicable for AIS equipment used on craft that are not covered by a mandatory carriage
requirement of AIS under SOLAS Chapter V.
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 60945:2002, Maritime navigation and radiocommunication equipment and systems –
General requirements – Methods of testing and required test results
IEC 61108 (all parts), Maritime navigation and radio communication equipment and systems
– Global navigation satellite systems (GNSS)
IEC 61108-4, Maritime navigation and radio communication equipment and systems – Global
navigation satellite systems (GNSS) – Part 4: Shipborne DGPS and DGLONASS maritime
radio beacon receiver equipment – Performance requirements, methods of testing and
required test results
IEC 61162 (all parts), Maritime navigation and radiocommunication equipment and systems
– Digital interfaces
– 10 – 62287-2 © IEC:2013(E)
IEC 61162-1, Maritime navigation and radiocommunication equipment and systems – Digital
interfaces – Part 1: Single talker and multiple listeners
IEC 61993-2, Maritime navigation and radio communication equipment and systems –
Automatic identification systems (AIS) – Part 2: Class A shipborne equipment of the universal
automatic identification system (AIS) – Operational and performance requirements, methods
of test and required test results
ITU Radio regulations 2012, Appendices
ITU-R Recommendation M.825-3:1998, Characteristics of a transponder system using digital
selective calling techniques for use with vessel traffic services and ship-to-ship identification
ITU-R Recommendation M.1084-5, Interim solutions for improved efficiency in the use of the
band 156-174 MHz by stations in the maritime mobile service
ITU-R Recommendation M.1371-4:2010, Technical characteristics for an automatic
identification system using time division multiple access in the VHF maritime mobile band
3 Abbreviations
AIS Automatic Identification System
BER Bit Error Rate
BIIT Built-In Integrity Tests
BT Bandwidth Time
COG Course over ground
CRC Cyclic Redundancy Check
CSD Compass Safe Distance
DGNSS Differential Global Navigation Satellite Service
DLS Data Link Service
DSC Digital Selective Calling
EUT Equipment under test
FM Frequency Modulation
GMSK Gaussian Minimum Shift Keying
GNSS Global Navigation Satellite Service
IMO International Maritime Organization
ITDMA Incremental Time Division Multiple Access
ITU International Telecommunication Union
LME Link Management Entity
MAC Medium access control
MMSI Maritime Mobile Service Identity
MSSA Multi-channel slot selection access
NM Nautical mile (1 NM = 1 852 m)
NRZI Non Return to Zero Inverted
OSI Open Systems Interconnection model
PER Packet Error Rate
PI Presentation Interface
RAIM Receiver autonomous integrity monitoring

62287-2 © IEC:2013(E) – 11 –
RATDMA Random Access Time Division Multiple Access
RF Radio Frequency
RR Radio Regulations
Rx Receive
SAR Search and rescue
SINAD Signal Interference Noise and Distortion ratio
SOG Speed over ground
SOTDMA Self Organised Time Division Multiple Access
TDMA Time Division Multiple Access
Tx Transmit
UTC Universal Time Co-ordinated
VDL VHF Data Link
VHF Very High Frequency
VSWR Voltage Standing Wave Ratio
VTS Vessel Traffic Services
NOTE Abbreviations included in the IEC 61162 series are not specified in the above list. Refer to this series of
International Standards for these abbreviations.
4 General requirements
4.1 General
4.1.1 Capabilities of the Class B “SO” AIS
The Class B “SO” AIS shall improve the safety of navigation by assisting in the efficient
navigation of ships and small craft, protection of the environment, and operation of Vessel
Traffic Services (VTS).
The Class B “SO” AIS station shall be inter-operable and compatible with all AIS stations
operating on the AIS VHF Data Link. In particular, Class B “SO” AIS stations shall not
degrade the integrity of the AIS VHF Data Link.
The Class B “SO” AIS shall be capable of providing information from the craft, automatically,
continuously and with the required accuracy and update rate
• in a ship-to-ship mode for collision avoidance,
• as a means for littoral States to obtain information about the craft, and
• as a VTS tool, i.e. ship-to-shore (traffic management).
4.1.2 Quality assurance
(See 10.1.1)
Manufacturers shall have a quality control system audited by a competent authority to ensure
continuous compliance with the requirements of this standard. Alternatively, the manufacturer
may use final product verification procedures where a competent authority verifies compliance
with the requirements of this standard before the product is put to the market.
NOTE The ISO 9000 series, as applicable, meets the requirements of a quality control system.
4.1.3 Safety of operation
(See 10.1.2)
– 12 – 62287-2 © IEC:2013(E)
It shall not be possible for the operator to augment, amend or erase any program software
required for operation in accordance with this equipment standard. The manufacturer may
provide means to install software updates.
Data used during operation and stored in the system shall be protected in such a way that
necessary modifications and amendments by the user cannot endanger its integrity and
correctness.
4.1.4 Additional features
(See 10.1.3, 13.6)
Where equipment provides a feature that is additional to the minimum requirements and
options of this standard, the operation and, as far as is reasonably practicable, the
malfunction of such additional features shall not degrade the performance of the equipment.
4.1.5 Functionality
The equipment shall operate in three modes (see 7.3.4.3):
• autonomous (default mode);
• assigned;
• interrogation.
4.2 Manuals
(See 10.1.1)
The manuals shall include the
• type of external connectors, if applicable,
• information for correct installation and positioning of the antennas,
• information for compass safe distance.
4.3 Marking and identification
(See 10.1.1)
In addition to the requirements of IEC 60945:2002, 4.9, the markings shall include:
• details of the power supply from which the equipment is intended to be operated;
• if applicable, the date by which batteries need to be replaced.
5 Environmental, power supply, interference and safety requirements
(See Clause 9)
In addition to the specific requirements of this standard, the Class B “SO” AIS shall fulfil the
following general requirements as detailed in IEC 60945:
• inter-unit connection (electrical interfaces other than IEC 61162 are permissible);
• power supply;
• extreme power supply;
• excessive conditions;
• power supply short-term variation and power supply failure;
• durability and resistance to environmental conditions;
• interference;
62287-2 © IEC:2013(E) – 13 –
• electromagnetic compatibility;
• compass safe distance;
• safety precautions;
• protection against accidental access to dangerous voltages;
• electromagnetic radiofrequency radiation.
The Class B “SO” AIS shall not enter an undefined or unstable state in case of under voltage.
The manufacturer shall declare the category of the equipment as follows:
a) portable;
b) protected from the weather;
c) exposed to the weather;
d) submerged or in continuous contact with sea water.
The Class B “SO” AIS shall be tested for compliance with the environmental, power supply,
special-purpose and safety requirements of IEC 60945.
• AIS equipment declared for protected installation shall meet the requirements described in
Table 3 column "Protected" of IEC 60945:2002;
• exposed AIS equipment shall meet the requirements described in Table 3, column
"Exposed" of IEC 60945;
• portable AIS equipment shall meet the requirements of Table 3 of IEC 60945:2002
"Protected" or "Exposed" as appropriate.
In addition, the AIS installation, when operating, shall not be damaged by the effects of open
circuited or short circuited antenna terminals.
6 Performance requirements
6.1 Internal processes
(See 10.1.1)
The Class B “SO” AIS shall comprise:
• a communication processor, capable of operating in the VHF Maritime Mobile Service
band;
• at least one transmitter and two receiving processes for TDMA op
...

IEC 62287-2 ®
Edition 1.0 2013-03
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Maritime navigation and radiocommunication equipment and systems –
Class B shipborne equipment of the automatic identification system (AIS) –
Part 2: Self-organising time division multiple access (SOTDMA) techniques

Matériels et systèmes de navigation et de radiocommunication maritimes –
Transpondeur embarqué du système d'identification automatique (AIS)
de classe B –
Partie 2: Techniques auto-organisées d'accès multiple par répartition dans le
temps (SOTDMA)
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IEC 62287-2 ®
Edition 1.0 2013-03
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Maritime navigation and radiocommunication equipment and systems –

Class B shipborne equipment of the automatic identification system (AIS) –

Part 2: Self-organising time division multiple access (SOTDMA) techniques

Matériels et systèmes de navigation et de radiocommunication maritimes –

Transpondeur embarqué du système d'identification automatique (AIS)

de classe B –
Partie 2: Techniques auto-organisées d'accès multiple par répartition dans le

temps (SOTDMA)
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 47.020.70 ISBN 978-2-8322-5025-9

– 2 – IEC 62287-2:2013 © IEC 2013

CONTENTS
FOREWORD . 7
1 Scope . 9
2 Normative references . 9
3 Abbreviations . 10
4 General requirements . 11
4.1 General . 11
4.1.1 Capabilities of the Class B “SO” AIS . 11
4.1.2 Quality assurance . 11
4.1.3 Safety of operation . 11
4.1.4 Additional features . 12
4.1.5 Functionality . 12
4.2 Manuals . 12
4.3 Marking and identification . 12
5 Environmental, power supply, interference and safety requirements . 12
6 Performance requirements . 13
6.1 Internal processes . 13
6.2 Operating frequency channels . 14
6.3 Internal GNSS receiver for position reporting. 14
6.4 Identification . 14
6.5 AIS Information . 14
6.5.1 Information content . 14
6.5.2 Information reporting intervals . 15
6.5.3 Short safety-related messages . 16
6.5.4 Permissible initialisation period . 16
6.6 Alarms and indications, fall-back arrangements . 16
6.6.1 Built-in integrity tests (BIIT) . 16
6.6.2 Transmitter shutdown procedure . 17
6.6.3 Position sensor fallback conditions . 18
6.7 User interface . 18
6.7.1 Indication and display . 18
6.7.2 Static data input . 19
6.7.3 External interfaces . 19
6.8 Protection from invalid control commands . 19
7 Technical requirements . 19
7.1 General . 19
7.2 Physical layer . 20
7.2.1 General . 20
7.2.2 Receiver characteristics . 20
7.2.3 Other characteristics . 21
7.2.4 Transmitter requirements . 22
7.3 Link layer . 23
7.3.1 General . 23
7.3.2 Link sub-layer 1: Medium Access Control (MAC) . 23
7.3.3 Link sub-layer 2: Data Link Service (DLS). 25
7.3.4 Link sub-layer 3: Link Management Entity (LME) . 25
7.4 Network layer . 29

7.4.1 General . 29
7.4.2 Management of regional operating settings. 29
7.4.3 Multi-channel operation . 30
7.5 Transport layer . 30
7.6 Presentation Interface . 31
7.7 DSC receive capability . 31
8 Test conditions . 31
8.1 General . 31
8.2 Normal test conditions . 31
8.2.1 Temperature and humidity . 31
8.2.2 Power supply . 31
8.3 Extreme test conditions . 31
8.4 Test signals . 31
8.4.1 Standard test signal number 1 . 31
8.4.2 Standard test signal number 2 . 32
8.4.3 Standard test signal number 3 . 32
8.4.4 Standard test signal number 4 . 32
8.5 Standard test environment . 33
8.5.1 Test setup . 33
8.5.2 Sensor test input . 33
8.5.3 Synchronisation . 33
8.5.4 Test signals applied to the receiver input . 33
8.5.5 Waiver for receivers . 34
8.5.6 Artificial antenna (dummy load) . 34
8.5.7 Modes of operation of the transmitter . 34
8.5.8 Common test conditions for protection from invalid controls . 34
8.5.9 Measurement uncertainties . 34
9 Power supply, environmental and EMC tests . 35
9.1 Test summary. 35
9.2 Vibration . 36
9.2.1 Purpose . 36
9.2.2 Method of measurement . 36
9.2.3 Required results . 36
9.3 Shock . 36
9.3.1 Purpose . 36
9.3.2 Method of measurement . 36
9.3.3 Required result . 36
9.4 Performance tests / checks . 36
9.5 Under voltage test (brown out) . 37
9.5.1 Purpose . 37
9.5.2 Method of test . 37
9.5.3 Required result . 37
9.6 Under voltage test (short term) . 37
9.6.1 Purpose . 37
9.6.2 Method of test . 37
9.6.3 Required result . 37
10 Operational tests . 37
10.1 General . 37
10.1.1 Tests by inspection . 37

– 4 – IEC 62287-2:2013 © IEC 2013
10.1.2 Safety of operation . 38
10.1.3 Additional features . 38
10.2 Modes of operation . 38
10.2.1 Autonomous mode . 38
10.2.2 Single messages . 40
10.2.3 Polled mode / Interrogation response . 43
10.3 Channel selection . 44
10.3.1 Valid channels . 44
10.3.2 Invalid channels. 44
10.4 Internal GNSS receiver . 44
10.5 AIS information. 45
10.5.1 Information content . 45
10.5.2 Information update intervals . 45
10.6 Initialisation period . 47
10.6.1 Purpose . 47
10.6.2 Method of measurement . 47
10.6.3 Required results . 47
10.7 Alarms and indications, fall-back arrangements . 47
10.7.1 Built in integrity test . 47
10.7.2 Transceiver protection . 48
10.7.3 Transmitter shutdown procedure . 48
10.7.4 Position sensor fallback conditions . 48
10.8 User interface . 49
10.8.1 Status indication . 49
10.8.2 Message display . 49
10.8.3 Static data input . 50
11 Physical tests . 51
11.1 TDMA transmitter . 51
11.1.1 Frequency error . 51
11.1.2 Carrier power . 51
11.1.3 Transmission spectrum . 52
11.1.4 Modulation accuracy . 53
11.1.5 Transmitter output power versus time function . 54
11.2 TDMA receivers . 55
11.2.1 Sensitivity . 55
11.2.2 Error behaviour at high input levels . 56
11.2.3 Co-channel rejection . 56
11.2.4 Adjacent channel selectivity . 57
11.2.5 Spurious response rejection . 57
11.2.6 Intermodulation response rejection . 60
11.2.7 Blocking or desensitisation . 62
11.3 Conducted spurious emissions . 62
11.3.1 Spurious emissions from the receiver . 62
11.3.2 Spurious emissions from the transmitter . 63
12 Specific tests of Link layer . 63
12.1 TDMA synchronisation . 64
12.1.1 Synchronisation test using UTC direct and indirect . 64
12.1.2 Synchronisation test without UTC, EUT receiving semaphore . 64
12.2 Time division (frame format) . 65

12.2.1 Purpose . 65
12.2.2 Method of measurement . 65
12.2.3 Required results . 65
12.3 Synchronisation jitter . 65
12.3.1 Definition . 65
12.3.2 Purpose . 65
12.3.3 Method of measurement . 65
12.3.4 Required results . 65
12.4 Data encoding (bit stuffing) . 65
12.4.1 Purpose . 65
12.4.2 Method of measurement . 65
12.4.3 Required results . 66
12.5 Frame check sequence . 66
12.5.1 Purpose . 66
12.5.2 Method of measurement . 66
12.5.3 Required results . 66
12.6 Slot allocation (Channel access protocols) . 66
12.6.1 Network entry . 66
12.6.2 Autonomous scheduled transmissions (SOTDMA) . 66
12.6.3 Autonomous scheduled transmissions (ITDMA) . 67
12.6.4 Transmission of Messages 24A and 24B (ITDMA) . 67
12.6.5 Assigned operation . 67
12.6.6 Group assignment . 69
12.6.7 Base station reservations . 73
12.7 Message formats . 74
12.7.1 Received messages. 74
12.7.2 Transmitted messages . 74
13 Specific tests of network layer . 74
13.1 Regional area designation by VDL Message . 74
13.1.1 Purpose . 74
13.1.2 Method of measurement . 74
13.1.3 Required results . 75
13.2 Channel management by addressed Message 22 . 76
13.2.1 Purpose . 76
13.2.2 Method of measurement . 76
13.2.3 Required results . 76
13.3 Invalid regional operating areas. 76
13.3.1 Purpose . 76
13.3.2 Method of measurement . 76
13.3.3 Required test results . 76
13.4 Continuation of autonomous mode reporting interval . 76
13.4.1 Purpose . 76
13.4.2 Method of test . 77
13.4.3 Required result . 77
13.5 Slot reuse and FATDMA reservations . 77
13.5.1 Method of measurement . 77
13.5.2 Required results . 77
13.6 Other features . 77
Annex A (normative) DSC channel management . 78

– 6 – IEC 62287-2:2013 © IEC 2013
Annex B (normative) Calculation of area size . 86
Bibliography . 87

Figure 1 – OSI layer model . 20
Figure 2 – Power versus time mask . 24
Figure 3 – Format for repeating four-packet cluster . 32
Figure 4 – Measurement arrangement for carrier power . 51
Figure 5 – Emission mask . 53
Figure 6 – Measurement arrangement for modulation accuracy . 53
Figure 7 – Measurement arrangement . 55
Figure 8 – Measurement arrangement with two generators . 56
Figure 9 – SINAD or PER/BER measuring equipment . 59
Figure 10 – Measurement arrangement for intermodulation . 61
Figure 11 – Regional transitional zones . 75

Table 1 – Dynamic information autonomous reporting intervals for Class B “SO” AIS . 16
Table 2 – BIIT and reaction to malfunctions . 17
Table 3 – Position sensor fallback conditions . 18
Table 4 – Required receiver performance . 21
Table 5 – Transceiver characteristics . 21
Table 6 – Transmitter characteristics . 23
Table 7 – Definitions of timing for Figure 2 . 25
Table 8 – Use of VDL Messages by a Class B “SO” AIS . 28
Table 9 – Content of first two packets . 32
Table 10 – Fixed PRS data derived from Recommendation ITU-T O.153 . 33
Table 11 – Test . 35
Table 12 – Peak frequency deviation versus time. 54
Table 13 – Frequencies for intermodulation test . 61
Table 14 – Regional area scenario . 75
Table 15 – Required channels in use . 75
Table A.1 – DSC monitoring times . 79
Table B.1 – Coordinate points . 86

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
MARITIME NAVIGATION AND RADIOCOMMUNICATION
EQUIPMENT AND SYSTEMS –
CLASS B SHIPBORNE EQUIPMENT OF
THE AUTOMATIC IDENTIFICATION SYSTEM (AIS) –

Part 2: Self-organising time division multiple access
(SOTDMA) techniques
FOREWORD
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patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 62287-2 has been prepared by IEC technical committee 80:
Maritime navigation and radiocommunication equipment and systems.
This bilingual version (2017-11) corresponds to the monolingual English version, published in
2013-03.
The text of this standard is based on the following documents:
FDIS Report on voting
80/685/FDIS 80/691/RVD
– 8 – IEC 62287-2:2013 © IEC 2013

Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
The French version of this standard has not been voted upon.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all parts in the IEC 62287 series, published under the general title Maritime
navigation and radiocommunication and systems – Class B shipborne equipment of the
automatic identification system (AIS), 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.
IMPORTANT – The 'colour inside' logo on the cover page of this publication indicates
that it contains colours which are considered to be useful for the correct
understanding of its contents. Users should therefore print this document using a
colour printer.
MARITIME NAVIGATION AND RADIOCOMMUNICATION
EQUIPMENT AND SYSTEMS –
CLASS B SHIPBORNE EQUIPMENT OF
THE AUTOMATIC IDENTIFICATION SYSTEM (AIS) –

Part 2: Self-organising time division multiple access
(SOTDMA) techniques
1 Scope
This part of IEC 62287 specifies operational and performance requirements, methods of
testing and required test results for Class B “SO” shipborne AIS equipment using Self-
organised TDMA (SOTDMA) techniques as described in Recommendation ITU-R M.1371. This
standard takes into account other associated IEC International Standards and existing
national standards, as applicable.
The main differences between Class B “CS” (IEC 62287-1) and Class B “SO” units are that
the Class B “SO”:
• covers all 25 kHz channels listed in Recommendation ITU-R M.1084-5;
• only uses the internal GNSS, no position sensor input is allowed;
• requires use of VDL Message 17 for correction of the internal GNSS;
• has a presentation interface;
• has additional reporting intervals, down to 5 s;
• has two power settings, with a high level of 5 W;
• has the capability to transmit binary messages.
It is applicable for AIS equipment used on craft that are not covered by a mandatory carriage
requirement of AIS under SOLAS Chapter V.
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 60945:2002, Maritime navigation and radiocommunication equipment and systems –
General requirements – Methods of testing and required test results
IEC 61108 (all parts), Maritime navigation and radio communication equipment and systems
– Global navigation satellite systems (GNSS)
IEC 61108-4, Maritime navigation and radio communication equipment and systems – Global
navigation satellite systems (GNSS) – Part 4: Shipborne DGPS and DGLONASS maritime
radio beacon receiver equipment – Performance requirements, methods of testing and
required test results
IEC 61162 (all parts), Maritime navigation and radiocommunication equipment and systems
– Digital interfaces
– 10 – IEC 62287-2:2013 © IEC 2013
IEC 61162-1, Maritime navigation and radiocommunication equipment and systems – Digital
interfaces – Part 1: Single talker and multiple listeners
IEC 61993-2, Maritime navigation and radio communication equipment and systems –
Automatic identification systems (AIS) – Part 2: Class A shipborne equipment of the universal
automatic identification system (AIS) – Operational and performance requirements, methods
of test and required test results
ITU Radio regulations 2012, Appendices
ITU-R Recommendation M.825-3:1998, Characteristics of a transponder system using digital
selective calling techniques for use with vessel traffic services and ship-to-ship identification
ITU-R Recommendation M.1084-5, Interim solutions for improved efficiency in the use of the
band 156-174 MHz by stations in the maritime mobile service
ITU-R Recommendation M.1371-4:2010, Technical characteristics for an automatic
identification system using time division multiple access in the VHF maritime mobile band
3 Abbreviations
AIS Automatic Identification System
BER Bit Error Rate
BIIT Built-In Integrity Tests
BT Bandwidth Time
COG Course over ground
CRC Cyclic Redundancy Check
CSD Compass Safe Distance
DGNSS Differential Global Navigation Satellite Service
DLS Data Link Service
DSC Digital Selective Calling
EUT Equipment under test
FM Frequency Modulation
GMSK Gaussian Minimum Shift Keying
GNSS Global Navigation Satellite Service
IMO International Maritime Organization
ITDMA Incremental Time Division Multiple Access
ITU International Telecommunication Union
LME Link Management Entity
MAC Medium access control
MMSI Maritime Mobile Service Identity
MSSA Multi-channel slot selection access
NM Nautical mile (1 NM = 1 852 m)
NRZI Non Return to Zero Inverted
OSI Open Systems Interconnection model
PER Packet Error Rate
PI Presentation Interface
RAIM Receiver autonomous integrity monitoring

RATDMA Random Access Time Division Multiple Access
RF Radio Frequency
RR Radio Regulations
Rx Receive
SAR Search and rescue
SINAD Signal Interference Noise and Distortion ratio
SOG Speed over ground
SOTDMA Self Organised Time Division Multiple Access
TDMA Time Division Multiple Access
Tx Transmit
UTC Universal Time Co-ordinated
VDL VHF Data Link
VHF Very High Frequency
VSWR Voltage Standing Wave Ratio
VTS Vessel Traffic Services
NOTE Abbreviations included in the IEC 61162 series are not specified in the above list. Refer to this series of
International Standards for these abbreviations.
4 General requirements
4.1 General
4.1.1 Capabilities of the Class B “SO” AIS
The Class B “SO” AIS shall improve the safety of navigation by assisting in the efficient
navigation of ships and small craft, protection of the environment, and operation of Vessel
Traffic Services (VTS).
The Class B “SO” AIS station shall be inter-operable and compatible with all AIS stations
operating on the AIS VHF Data Link. In particular, Class B “SO” AIS stations shall not
degrade the integrity of the AIS VHF Data Link.
The Class B “SO” AIS shall be capable of providing information from the craft, automatically,
continuously and with the required accuracy and update rate
• in a ship-to-ship mode for collision avoidance,
• as a means for littoral States to obtain information about the craft, and
...