IEC 62320-3:2015

Maritime navigation and radiocommunication equipment and systems - Automatic identification systems (AIS) - Part 3: Repeater stations - Minimum operational and performance requirements - Methods of test and required test results

IEC 62320-3:2015 specifies the minimum operational and performance requirements, methods of testing and required test results for AIS repeater stations, compatible with the performance standards adopted by IMO Res. MSC.74 (69), annex 3, Universal AIS. It incorporates the technical characteristics of non-shipborne, fixed station AIS equipment, included in Recommendation ITU-R M.1371 and IALA Recommendation A-124. Where applicable, it also takes into account the ITU Radio Regulations. This standard takes into account other associated IEC International Standards and existing national standards, as applicable. This standard is applicable for AIS repeater stations. It does not include specifications for the display of AIS data on shore.

Matériels et systèmes de navigation et de radiocommunication maritimes - Systèmes d'identification automatique (SIA) - Partie 3: Station de répéteurs - Exigences minimales d'exploitation et de performances - Méthodes d’essai et résultats d’essai exigibles

L'IEC 62320-3:2015 spécifie les exigences minimales d'exploitation et de performances, les méthodes d'essai et les résultats exigibles pour les stations de répéteurs SIA conformes aux normes de performances adoptées par l'Annexe 3 de la Résolution MSC.74 (69) de l'OMI, SIA universel. Elle intègre les caractéristiques techniques des systèmes SIA de station fixe non embarquée, incluses dans la Recommandation UIT-R M.1371 et la Recommandation IALA A-124. Le cas échéant, elle tient compte également des réglementations de radiodiffusion de l'UIT. La présente norme s'appuie sur d'autres Normes internationales de l'IEC associées et sur des normes nationales existantes, selon le cas.
La présente norme s'applique aux stations de répéteurs SIA. Elle n'inclut pas les spécifications pour l'affichage des données SIA à terre.

General Information

• Status: Published
• Publication Date: 27-Jan-2015
• 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: PPUB - Publication issued
• Start Date: 28-Jan-2015
• Completion Date: 28-Feb-2015

Overview

IEC 62320-3:2015 specifies the minimum operational and performance requirements, test methods and required test results for shore-based Automatic Identification System (AIS) repeater stations. The standard ensures repeater stations are compatible with IMO performance standards (IMO Res. MSC.74 (69), annex 3 - Universal AIS) and incorporates technical characteristics from Recommendation ITU‑R M.1371 and IALA Recommendation A‑124. It applies specifically to non‑shipborne, fixed AIS repeater equipment and does not cover how AIS data is displayed on shore.

Key topics and technical requirements

The standard covers comprehensive functional, performance and test requirements for AIS repeater stations, including:

• Functional requirements

  • Types of repeater stations and repeating operation
  • Synchronization and access to the VDL (VHF Data Link)
  • Configuration structures and message formatting

• Repeating rules and message handling

  • Duplicate message filtering, content and channel filtering
  • Reporting-interval and position‑based filtering
  • Overload protection, RSSI‑based slot selection and message scheduling
  • Repeater station identification message structure

• Physical and link layer performance

  • Transmitter and receiver requirements (TDMA transmitter/receiver tests)
  • Frequency error, carrier power, modulation spectrum and intermodulation
  • Receiver sensitivity, co‑channel/adjacent channel rejection, blocking/desensitisation
  • Power consumption and environmental conditions

• Test methods and required results

  • Configuration and basic functional tests (including FATDMA/RATDMA/ITDMA access)
  • VDL access and repetition‑rate tests, filtering behaviour verification
  • Physical radio tests, spurious emissions and transceiver protection
  • Normative configuration annex and informative test-area arrangements

Practical applications - who uses this standard

IEC 62320-3:2015 is used by maritime stakeholders involved in shore‑based AIS infrastructure and certification:

• Manufacturers of AIS repeater stations and shore-based maritime communications equipment (for design and factory testing)
• Testing and certification laboratories performing conformity, type‑approval and performance testing
• Maritime administrations, harbour/port authorities and coastal surveillance operators deploying or auditing AIS repeater installations
• System integrators and consultants implementing coastal VDL networks and traffic‑management systems
• Regulatory bodies verifying compliance with IMO, ITU and IALA requirements

Related standards

• IMO Res. MSC.74 (69), annex 3 (Universal AIS)
• ITU‑R M.1371 (AIS technical characteristics)
• IALA Recommendation A‑124
• Other IEC standards referenced for environmental and electrical testing

Keywords: IEC 62320-3:2015, AIS repeater stations, Automatic Identification System, maritime navigation, AIS repeater testing, VDL access, TDMA transmitter/receiver, IMO universal AIS.

Standards Content (Sample)

IEC 62320-3 ®
Edition 1.0 2015-01
INTERNATIONAL
STANDARD
colour
inside
Maritime navigation and radiocommunication equipment and systems –
Automatic identification system (AIS) –
Part 3: Repeater stations – Minimum operational and performance
requirements – Methods of test and required test results

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IEC 62320-3 ®
Edition 1.0 2015-01
INTERNATIONAL
STANDARD
colour
inside
Maritime navigation and radiocommunication equipment and systems –

Automatic identification system (AIS) –

Part 3: Repeater stations – Minimum operational and performance

requirements – Methods of test and required test results

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 47.020.70 ISBN 978-2-8322-2237-9

– 2 – IEC 62320-3:2015  IEC 2015
CONTENTS
FOREWORD . 6
INTRODUCTION . 8
1 Scope . 9
2 Normative references . 9
3 Symbols and abbreviations . 10
4 Functional requirements for a repeater station . 11
4.1 General . 11
4.1.1 Types of repeater stations . 11
4.1.2 Repeating operation . 11
4.1.3 Synchronisation . 12
4.1.4 Access to the VDL . 12
4.1.5 Configuration . 13
4.2 Functional block diagram of an AIS repeater station . 13
4.3 Repeating rules. 14
4.3.1 General repeating rules . 14
4.3.2 Repeater station use of repeat indicator . 15
4.3.3 Duplicate message filtering . 15
4.3.4 Content filtering . 16
4.3.5 Reporting interval filtering . 19
4.3.6 Channel filtering . 19
4.3.7 Filtering procedure . 19
4.3.8 Message processing . 21
4.3.9 Overload protection . 21
4.3.10 Slot selection using RSSI – RSSI measurement . 22
4.4 Message scheduling . 22
4.4.1 Station report . 22
4.4.2 Repeater station identification message structure . 23
4.4.3 Broadcast active AIS-SART message . 24
4.4.4 Configuration parameters . 24
4.5 Repeater station input/output sentence formatters . 29
5 Performance requirements. 30
5.1 Cyclic redundancy check. 30
5.2 Physical layer requirement . 30
5.2.1 Transmitter requirements . 30
5.2.2 Receiver requirements . 34
5.2.3 Power consumption . 34
5.2.4 Environmental requirements . 35
5.3 Link layer requirements . 35
6 Functional tests . 35
6.1 Configuration tests . 35
6.1.1 Factory default settings . 35
6.1.2 Standard test set-up . 36
6.1.3 Configuration via VDL . 37
6.2 Basic functional tests . 38
6.2.1 Basic repetition test . 38
6.2.2 Power setting . 38

6.2.3 Repeat indicator handling . 39
6.2.4 Synchronisation jitter . 40
6.3 VDL access. 41
6.3.1 RATDMA . 41
6.3.2 FATDMA access . 44
6.3.3 ITDMA access . 44
6.4 Repetition rates . 45
6.4.1 Downsampling . 45
6.4.2 Fixed repetition interval . 46
6.4.3 Maximum VDL load . 46
6.4.4 Maximum transmissions per second . 47
6.4.5 Age of time stamp . 47
6.5 Filtering . 48
6.5.1 Duplicate filtering . 48
6.5.2 Channel filtering . 48
6.5.3 Position filtering . 49
6.5.4 Message type filtering . 51
6.5.5 Message content filtering . 51
6.5.6 AIS-SART filtering . 56
6.6 Repeater station identification message . 56
6.6.1 Purpose . 56
6.6.2 Method of measurement . 56
6.6.3 Required results . 57
7 Test conditions . 57
7.1 Normal and extreme test conditions . 57
7.1.1 Normal test conditions . 57
7.1.2 Extreme test conditions . 57
7.2 Additional test arrangements. 57
7.2.1 Arrangements for test signals applied to the receiver input . 57
7.2.2 Encoder for receiver measurements . 58
7.2.3 Waiver for receivers . 58
7.2.4 Impedance . 58
7.2.5 Artificial antenna (dummy load) . 58
7.2.6 Facilities for access . 58
7.2.7 Modes of operation of the transmitter. 58
7.3 Measurement uncertainties . 58
7.4 Test signals . 59
7.4.1 Standard test signal number 1 . 59
7.4.2 Standard test signal number 2 . 59
7.4.3 Standard test signal number 3 . 59
7.4.4 Standard test signal number 4 . 59
8 Physical radio tests . 60
8.1 Transceiver protection test . 60
8.1.1 Purpose . 60
8.1.2 Method of measurement . 60
8.1.3 Required results . 61
8.2 TDMA transmitter . 61
8.2.1 General . 61
8.2.2 Frequency error . 61

– 4 – IEC 62320-3:2015  IEC 2015
8.2.3 Carrier power . 61
8.2.4 Modulation spectrum slotted transmission . 62
8.2.5 Transmitter test sequence and modulation accuracy verification . 63
8.2.6 Transmitter output power versus time function . 64
8.2.7 Intermodulation attenuation (Type 1 only) . 66
8.3 TDMA receivers . 67
8.3.1 Sensitivity . 67
8.3.2 Error behaviour at high input levels. 68
8.3.3 Co-channel rejection . 68
8.3.4 Adjacent channel selectivity . 69
8.3.5 Spurious response rejection . 70
8.3.6 Intermodulation response rejection . 72
8.3.7 Blocking or desensitisation . 73
8.3.8 Conducted spurious emissions at the antenna . 74
Annex A (normative) Configuration structures . 75
A.1 General . 75
A.2 PI sentences for repeater stations . 77
A.2.1 RFS – Repeater station FATDMA slots . 77
A.2.2 RMF – Repeater station MMSI filter . 79
A.2.3 Area configuration . 79
A.3 Configuration via VDL using Message 26 . 83
Annex B (informative) Test area arrangement . 103
Bibliography . 104

Figure 1 – Functional block diagram of an AIS repeater station . 14
Figure 2 – Power versus time characteristics . 32
Figure 3 – Format for repeating four-packet cluster . 60
Figure 4 – Measurement arrangement . 61
Figure 5 – Measurement arrangement . 62
Figure 6 – Modulation spectrum for slotted transmission . 63
Figure 7 – Measurement arrangement . 63
Figure 8 – Power versus time characteristics . 65
Figure 9 – Measurement arrangement . 66
Figure 10 – Measurement arrangement . 67
Figure 11 – Measurement arrangement . 68
Figure 12 – Measurement arrangement . 68
Figure 13 – Measurement arrangement . 69
Figure 14 – SINAD or PER/BER measuring equipment . 71
Figure 15 – Measurement arrangement . 72
Figure 16 – Measurement arrangement . 73
Figure B.1 – Test area arrangement. 103

Table 1 – SOTDMA communication state of received station . 12
Table 2 – ITDMA Communication state of received station . 13
Table 3 – ITDMA communication state of received station with rescheduling . 13
Table 4 – Duplicate message filtering parameters . 16
Table 5 – Repeater station behaviour for message repeat . 17

Table 6 – Contents of Message 26 used for repeater station identification . 23
Table 7 – Alarm status definition for Table 6 . 24
Table 8 – Message 8 structure with AIS-SART related content . 24
Table 9 – Configurable parameters . 25
Table 10 – Repetition parameters . 26
Table 11 – Area related configuration parameters . 28
Table 12 – Repeater station input/output sentence formatters . 30
Table 13 – Transmitter parameters . 31
Table 14 – Power versus time characteristics for Figure 2 . 32
Table 15 – Required parameter settings for a repeater station . 33
Table 16 – Required settings of physical layer constants . 33
Table 17 – Modulation parameters of the physical layer of the repeater station . 33
Table 18 – Required receiver characteristics . 34
Table 19 – Factory default values . 35
Table 20 – Standard test set-up . 36
Table 21 – Test area of standard test set-up . 37
Table 22 – Content of first two packets . 60
Table 23 – Fixed PRS data derived from Recommendation ITU-T O.153 . 60
Table 24 – Power versus time characteristics . 65
Table 25 – Frequencies for intermodulation tests . 73
Table A.1 – Basic system parameters . 76
Table A.2 – General repetition parameters . 77
Table A.3 – Basic structure of Message 26 . 84
Table A.4 – Message 26 repeater command IDs . 84
Table A.5 – EPV configuration . 85
Table A.6 – EPV query. 86
Table A.7 – Property identifiers for use with EPV – Basic system parameters . 87
Table A.8 – Property identifiers for use with EPV – General repetition parameters . 88
Table A.9 – AES key configuration . 89
Table A.10 – RFS configuration . 90
Table A.11 – RFS query . 91
Table A.12 – RMF configuration . 92
Table A.13 – RMF query . 93
Table A.14 – RA1 configuration . 94
Table A.15 – RA1 query . 95
Table A.16 – RA2 configuration . 96
Table A.17 – RA2 query . 98
Table A.18 – RA3 configuration . 99
Table A.19 – RA3 query . 100
Table A.20 – RA4 configuration . 101
Table A.21 – RA4 query . 102

– 6 – IEC 62320-3:2015  IEC 2015
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
MARITIME NAVIGATION AND
RADIOCOMMUNICATION EQUIPMENT AND SYSTEMS –
AUTOMATIC IDENTIFICATION SYSTEM (AIS) –

Part 3: Repeater stations –
Minimum operational and performance requirements –
Methods of test and required test results

FOREWORD
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International Standard IEC 62320-3 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
80/744/FDIS 80/752/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 in the IEC 62320 series, published under the general title, Maritime
navigation and radiocommunication equipment and systems – 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 website 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.

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– 8 – IEC 62320-3:2015  IEC 2015
INTRODUCTION
Chapter V of the 1974 SOLAS Convention requires mandatory carriage of Automatic
Identification System (AIS) equipment on all vessels constructed on or after 01 July 2002.
Implementation for other types and sizes of SOLAS Convention vessels was required to be
completed not later than 31 December 2004.
SOLAS Chapter V, Regulation 19, section 2.4.5 states that AIS shall:
a) provide automatically to appropriate equipped shore stations, other ships and aircraft
information, including ship's identity, type, position, course, speed, navigational status and
other safety-related information;
b) receive automatically such information from similarly fitted ships;
c) monitor and track ships; and
d) exchange data with shore-based facilities.
In addition, the IMO Performance Standards for AIS states that:
• The AIS should improve the safety of navigation by assisting in the efficient navigation of
ships, protection of the environment, and operation of Vessel Traffic Services (VTS), by
satisfying the following functional requirements:
1) in a ship-to-ship mode for collision avoidance;
2) as a means for littoral States to obtain information about a ship and its cargo; and
3) as a VTS tool, i. e. ship-to-shore (traffic management).
• The AIS should be capable of providing to ships and to competent authorities, information
from the ship, automatically and with the required accuracy and frequency, to facilitate
accurate tracking. Transmission of the data should be with the minimum involvement of
ship's personnel and with a high level of availability.
The provision of Shore Based AIS will be necessary to attain the full benefit of the SOLAS
Convention requirements.
This standard provides the minimum operational and performance requirements, methods of
test and the required test results for AIS repeater stations. The testing is divided into two
parts, the logical tests and the transceiver tests. These are captured in Clause 6 and Clause 8
respectively.
MARITIME NAVIGATION AND
RADIOCOMMUNICATION EQUIPMENT AND SYSTEMS –
AUTOMATIC IDENTIFICATION SYSTEM (AIS) –

Part 3: Repeater stations –
Minimum operational and performance requirements –
Methods of test and required test results

1 Scope
This part of IEC 62320 specifies the minimum operational and performance requirements,
methods of testing and required test results for AIS repeater stations, compatible with the
performance standards adopted by IMO Res. MSC.74 (69), annex 3, Universal AIS. It
incorporates the technical characteristics of non-shipborne, fixed station AIS equipment,
included in Recommendation ITU-R M.1371 and IALA Recommendation A-124. Where
applicable, it also takes into account the ITU Radio Regulations. This standard takes into
account other associated IEC International Standards and existing national standards, as
applicable.
This standard is applicable for AIS repeater stations. It does not include specifications for the
display of AIS data on shore.
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, Maritime navigation and radiocommunication equipment and systems – General
requirements – Methods of testing and required test results
IEC 61162-1, Maritime navigation and radiocommunication equipment and systems – Digital
interfaces – Part 1: Single talker and multiple listeners
ITU-R Recommendation M.585, Assignment and use of identities in the maritime mobile
service
ITU-R Recommendation M.1084, 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, Technical characteristics for a universal shipborne
automatic identification system using time division multiple access in the VHF maritime mobile
band
ITU-T Recommendation O.153, Basic parameters for the measurement of error performance
at bit rates below the primary rate
ITU Radio Regulations, Appendix 18

– 10 – IEC 62320-3:2015  IEC 2015
3 Symbols and abbreviations
AES Advanced Encryption Standard
AIS Automatic Identification System
AtoN Aids To Navigation
BER Bit Error Rate
BFO Beat frequency oscillator
BIIT Built-In Integrity Tests
BT Bandwidth Time product
COG Course Over Ground
CS Carrier Sense
CSTDMA Carrier Sense Time Division Multiple Access
DAC Digital Area Code
dBc Decibel-carrier
dBm Decibel-milliwatts
EUT Equipment under test
FATDMA Fixed Access Time Division Multiple Access
FI Function Identifier
FIFO First in, first out
GNSS Global Navigation Satellite System
IALA International Association of Marine Aids to Navigation and Lighthouse
Authorities
ITDMA Incremental Time Division Multiple Access
IMO International Maritime Organization
ITU International Telecommunication Union
kn Knots
MMSI Maritime Mobile Service Identity
NavStatus Navigational Status
NM Nautical Mile
NRZI Non-Return to Zero Inverted
PER Packet Error Rate
Pc Carrier Power
PI Presentation Interface
PPS Pulse(s) Per Second
RATDMA Random Access Time Division Multiple Access
RSSI Received Signal Strength Indication
Rx Receive
AIS-SART Search And Rescue Transmitter
SO Self-Organizing
SOG Speed Over Ground
SOTDMA Self-Organizing Time Division Multiple Access
TDMA Time Division Multiple Access
Tx Transmit
UTC Coordinated Universal Time

VCO Voltage controlled oscillator
VDL VHF Data Link
VHF Very High Frequency
VSWR Voltage Standing Wave Ratio
VTS Vessel Traffic Services
4 Functional requirements for a repeater station
4.1 General
4.1.1 Types of repeater stations
AIS repeater stations are designed to retransmit VDL messages in one or several steps to
extend the receiving range in areas with impaired VHF coverage. Careful consideration needs
to be taken not to overload the VDL with repeated messages, considering the additional load
repeated messages generate. The AIS environment may also contain one or more repeaters.
A repeater station is a store and forward repeater process.
A repeater station is a non-controlling station on the VDL.
The repeater station can be one of two types.
Type 1:
• Radio requirements as per the AIS base station requirements
• A dedicated repeater station is a Type 1 device
Type 2:
• Radio requirements as per the AIS AtoN station requirements
• Restricted repeater capability
• Suitable for areas with low AIS activity only
These two types of repeater functions can be implemented in three different ways:
• As a dedicated repeater station (Type 1)
• As an internal process of an AIS Base Station (Type 1)
• As an internal process of an AIS AtoN device (Type 2)
4.1.2 Repeating operation
(See 6.2.1)
4.1.2.1 Modes of repeating operation
The repeater station is designed for independent operation in autonomous and assigned
mode. No polled mode is allowed.
4.1.2.2 Message by message repeating
Each received message that shall be repeated is internally allocated for transmission using
RATDMA, ITDMA, or FATDMA as supported and configured.
4.1.2.3 Message rescheduling
This mode is only applicable for scheduled position reports.

– 12 – IEC 62320-3:2015  IEC 2015
Received messages shall be analysed and the repeater station shall reschedule
transmissions using an ITDMA schedule.
The repeater station may reschedule repeated messages using a reporting interval different
from the original interval, depending on configuration.
4.1.3 Synchronisation
(See 6.2.4)
The repeater station shall primarily use an internal source for UTC direct synchronisation.
The repeater station can synchronise on any AIS station that has direct UTC (otherwise
known as UTC indirect). The repeater station shall have UTC direct, or UTC indirect and only
transmit when sync state is 0 or 1.
4.1.4 Access to the VDL
4.1.4.1 Means of access
Access to the VDL can be by using pre-configured transmission slots. Pre-configured
transmission slots shall in this case be reserved by Message 20 from a base station.
If pre-configured slots are not available, RATDMA may be used for transmission.
A repeater station shall use as a minimum RATDMA, ITDMA and FATDMA to allocate and
pre-announce transmissions.
The repeater station needs to take into account all received Message 20s. It shall respect slot
reservations. If a base station reserves slots for the repeater station, the repeater station shall
be configured to use FATDMA.
CSTDMA is not suitable for repeater stations and not permitted because of:
• slot start delay;
• no protection from collision with Class B CS units;
• only one slot messages;
• intentional slot reuse is not allowed.
4.1.4.2 RATDMA and FATDMA access scheme
(See 6.3.1, 6.3.2)
The repeater station shall not change the data content of the message, but shall change the
SOTDMA communication state or ITDMA if relevant. The repeater station shall change the
SOTDMA communication state as indicated in Table 1.
Table 1 – SOTDMA communication state of received station
Received parameter Transmit parameters
Synch state Change to Synch State of repeater station
Slot time out Set to zero
Slot offset Set to zero
The repeater station shall change the ITDMA communication state as indicated in Table 2.

Table 2 – ITDMA Communication state of received station
Received parameter Transmit parameters
Synch state Change to synch state of repeater
Slot increment Set to zero
Number of slots Set to zero
Keep flag Set to FALSE ( = 0)
4.1.4.3 ITDMA access scheme
(See 6.3.3)
The repeater station shall not change the data content of the message, but shall change the
SOTDMA communication state or ITDMA as relevant. The repeater station shall change the
SOTDMA or ITDMA communication state to an ITDMA communication state as described in
Table 2. When using ITDMA to reschedule refer to Table 3.
If ITDMA is used and the repeater station receives a Message 1 that shall be repeated, the
repeater station shall change the message ID from 1 to 3 to all ITDMA access scheme.
Table 3 – ITDMA communication state of received station with rescheduling
Received parameter Transmit parameters
Synch state Change to synch state of repeater station
Slot increment Offset set to next transmission slot
Number of slots As required for next repeated message
Keep flag Set to FALSE ( = 0)
ITDMA can be used to schedule transmissions that originate from different stations.
When using ITDMA reservations, the selection interval shall be 150 slots. Set the ITDMA
communication state at time of transmission to the next scheduled transmission.
4.1.5 Configuration
(See 6.1.3)
Initial configuration shall be possible using the presentation interface of the repeater station
as defined in Annex A.
The repeater station may use VDL Messages for configuration and status reports as defined
in Clause A.3.
4.2 Functional block diagram of an AIS repeater station
Figure 1 shows the principal components of the AIS repeater station.

– 14 – IEC 62320-3:2015  IEC 2015

Dedicated AIS Repeater station

I/O
Controller
AIS TX
Internal Sync AIS RX
Source
Power
AIS RX
BIIT
IEC
Figure 1 – Functional block diagram of an AIS repeater station
As a minimum, the following functional elements are required for the AIS repeater station:
• two multi-channel receiving processes;
• one multi-channel TDMA transmitter;
NOTE Since the minimum configuration of the repeater station has only one transmitter, the repeater station
cannot transmit on both AIS Channels (AIS A and AIS B) simultaneously.
• a controlling unit, which includes a unique identifier to the repeater station;
• an internal synchronisation source capable of providing UTC;
• a Built-In-Integrity-Test unit (BIIT), which shall provide alarms;
• a power supply;
• an interface with data format conforming to IEC 61162-1. The physical interface will be
determined by the manufacturer. The interface shall output VDO sentences for all
transmitted messages, and VDM sentences for all received messages. Additionally, the
repeater station shall be configurable using the PI. The repeater station shall be
configurable for repeater enable via the VDL, and may optionally be configurable for all
parameters via the VDL.
4.3 Repeating rules
4.3.1 General repeating rules
(See 6.2.1, 6.4.5)
The repeater station is a store-and-forward process and shall use the FIFO principle.
Retransmission of messages shall be performed as soon as possible, according to
configuration, after receiving the relevant messages which are required to be retransmitted.
The maximum delay of the retransmission shall be within 9 s of reception in order to ensure
one minute interval UTC time stamp in a position report that has undergone multiple
Presentation Interface
Antenna system
repetitions. If RATDMA is used to transmit a message, the received message can be held for
maximum 4 s and 10 slots.
With the exception of AIS-SART position reports, messages containing a time stamp older
than 30 s shall not be repeated.
The repeater station shall be capable of retransmission of a message within 10 slots of
reception of that received message.
Received position messages (Message 1, 2, 3 or 18) shall replac
...

IEC 62320-3 ®
Edition 1.0 2015-01
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Maritime navigation and radiocommunication equipment and systems –
Automatic identification system (AIS) –
Part 3: Repeater stations – Minimum operational and performance
requirements – Methods of test and required test results

Matériels et systèmes de navigation et de radiocommunication maritimes –
Systèmes d'identification automatique (SIA) –
Partie 3: Stations de répéteurs – Exigences minimales d'exploitation et de
performances – Méthodes d’essai et résultats d’essai exigés

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IEC 62320-3 ®
Edition 1.0 2015-01
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Maritime navigation and radiocommunication equipment and systems –

Automatic identification system (AIS) –

Part 3: Repeater stations – Minimum operational and performance

requirements – Methods of test and required test results

Matériels et systèmes de navigation et de radiocommunication maritimes –

Systèmes d'identification automatique (SIA) –

Partie 3: Stations de répéteurs – Exigences minimales d'exploitation et de

performances – Méthodes d’essai et résultats d’essai exigés

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 47.020.70 ISBN 978-2-8322-8083-6

– 2 – IEC 62320-3:2015  IEC 2015
CONTENTS
FOREWORD . 6
INTRODUCTION . 8
1 Scope . 9
2 Normative references . 9
3 Symbols and abbreviations . 10
4 Functional requirements for a repeater station . 11
4.1 General . 11
4.1.1 Types of repeater stations . 11
4.1.2 Repeating operation . 11
4.1.3 Synchronisation . 12
4.1.4 Access to the VDL . 12
4.1.5 Configuration . 13
4.2 Functional block diagram of an AIS repeater station . 13
4.3 Repeating rules. 14
4.3.1 General repeating rules . 14
4.3.2 Repeater station use of repeat indicator . 15
4.3.3 Duplicate message filtering . 15
4.3.4 Content filtering . 16
4.3.5 Reporting interval filtering . 19
4.3.6 Channel filtering . 19
4.3.7 Filtering procedure . 19
4.3.8 Message processing . 21
4.3.9 Overload protection . 21
4.3.10 Slot selection using RSSI – RSSI measurement . 22
4.4 Message scheduling . 22
4.4.1 Station report . 22
4.4.2 Repeater station identification message structure . 23
4.4.3 Broadcast active AIS-SART message . 24
4.4.4 Configuration parameters . 24
4.5 Repeater station input/output sentence formatters . 29
5 Performance requirements. 30
5.1 Cyclic redundancy check. 30
5.2 Physical layer requirement . 30
5.2.1 Transmitter requirements . 30
5.2.2 Receiver requirements . 34
5.2.3 Power consumption . 34
5.2.4 Environmental requirements . 35
5.3 Link layer requirements . 35
6 Functional tests . 35
6.1 Configuration tests . 35
6.1.1 Factory default settings . 35
6.1.2 Standard test set-up . 36
6.1.3 Configuration via VDL . 37
6.2 Basic functional tests . 38
6.2.1 Basic repetition test . 38
6.2.2 Power setting . 38

6.2.3 Repeat indicator handling . 39
6.2.4 Synchronisation jitter . 40
6.3 VDL access. 41
6.3.1 RATDMA . 41
6.3.2 FATDMA access . 44
6.3.3 ITDMA access . 44
6.4 Repetition rates . 45
6.4.1 Downsampling . 45
6.4.2 Fixed repetition interval . 46
6.4.3 Maximum VDL load . 46
6.4.4 Maximum transmissions per second . 47
6.4.5 Age of time stamp . 47
6.5 Filtering . 48
6.5.1 Duplicate filtering . 48
6.5.2 Channel filtering . 48
6.5.3 Position filtering . 49
6.5.4 Message type filtering . 51
6.5.5 Message content filtering . 51
6.5.6 AIS-SART filtering . 56
6.6 Repeater station identification message . 56
6.6.1 Purpose . 56
6.6.2 Method of measurement . 56
6.6.3 Required results . 57
7 Test conditions . 57
7.1 Normal and extreme test conditions . 57
7.1.1 Normal test conditions . 57
7.1.2 Extreme test conditions . 57
7.2 Additional test arrangements. 57
7.2.1 Arrangements for test signals applied to the receiver input . 57
7.2.2 Encoder for receiver measurements . 58
7.2.3 Waiver for receivers . 58
7.2.4 Impedance . 58
7.2.5 Artificial antenna (dummy load) . 58
7.2.6 Facilities for access . 58
7.2.7 Modes of operation of the transmitter. 58
7.3 Measurement uncertainties . 58
7.4 Test signals . 59
7.4.1 Standard test signal number 1 . 59
7.4.2 Standard test signal number 2 . 59
7.4.3 Standard test signal number 3 . 59
7.4.4 Standard test signal number 4 . 59
8 Physical radio tests . 60
8.1 Transceiver protection test . 60
8.1.1 Purpose . 60
8.1.2 Method of measurement . 60
8.1.3 Required results . 61
8.2 TDMA transmitter . 61
8.2.1 General . 61
8.2.2 Frequency error . 61

– 4 – IEC 62320-3:2015  IEC 2015
8.2.3 Carrier power . 61
8.2.4 Modulation spectrum slotted transmission . 62
8.2.5 Transmitter test sequence and modulation accuracy verification . 63
8.2.6 Transmitter output power versus time function . 64
8.2.7 Intermodulation attenuation (Type 1 only) . 66
8.3 TDMA receivers . 67
8.3.1 Sensitivity . 67
8.3.2 Error behaviour at high input levels. 68
8.3.3 Co-channel rejection . 68
8.3.4 Adjacent channel selectivity . 69
8.3.5 Spurious response rejection . 70
8.3.6 Intermodulation response rejection . 72
8.3.7 Blocking or desensitisation . 73
8.3.8 Conducted spurious emissions at the antenna . 74
Annex A (normative) Configuration structures . 75
A.1 General . 75
A.2 PI sentences for repeater stations . 77
A.2.1 RFS – Repeater station FATDMA slots . 77
A.2.2 RMF – Repeater station MMSI filter . 79
A.2.3 Area configuration . 79
A.3 Configuration via VDL using Message 26 . 83
Annex B (informative) Test area arrangement . 103
Bibliography . 104

Figure 1 – Functional block diagram of an AIS repeater station . 14
Figure 2 – Power versus time characteristics . 32
Figure 3 – Format for repeating four-packet cluster . 60
Figure 4 – Measurement arrangement . 61
Figure 5 – Measurement arrangement . 62
Figure 6 – Modulation spectrum for slotted transmission . 63
Figure 7 – Measurement arrangement . 63
Figure 8 – Power versus time characteristics . 65
Figure 9 – Measurement arrangement . 66
Figure 10 – Measurement arrangement . 67
Figure 11 – Measurement arrangement . 68
Figure 12 – Measurement arrangement . 68
Figure 13 – Measurement arrangement . 69
Figure 14 – SINAD or PER/BER measuring equipment . 71
Figure 15 – Measurement arrangement . 72
Figure 16 – Measurement arrangement . 73
Figure B.1 – Test area arrangement. 103

Table 1 – SOTDMA communication state of received station . 12
Table 2 – ITDMA Communication state of received station . 13
Table 3 – ITDMA communication state of received station with rescheduling . 13
Table 4 – Duplicate message filtering parameters . 16

Table 5 – Repeater station behaviour for message repeat . 17
Table 6 – Contents of Message 26 used for repeater station identification . 23
Table 7 – Alarm status definition for Table 6 . 24
Table 8 – Message 8 structure with AIS-SART related content . 24
Table 9 – Configurable parameters . 25
Table 10 – Repetition parameters . 26
Table 11 – Area related configuration parameters . 28
Table 12 – Repeater station input/output sentence formatters . 30
Table 13 – Transmitter parameters . 31
Table 14 – Power versus time characteristics for Figure 2 . 32
Table 15 – Required parameter settings for a repeater station . 33
Table 16 – Required settings of physical layer constants . 33
Table 17 – Modulation parameters of the physical layer of the repeater station . 33
Table 18 – Required receiver characteristics . 34
Table 19 – Factory default values . 35
Table 20 – Standard test set-up . 36
Table 21 – Test area of standard test set-up . 37
Table 22 – Content of first two packets . 60
Table 23 – Fixed PRS data derived from Recommendation ITU-T O.153 . 60
Table 24 – Power versus time characteristics . 65
Table 25 – Frequencies for intermodulation tests . 73
Table A.1 – Basic system parameters . 76
Table A.2 – General repetition parameters . 77
Table A.3 – Basic structure of Message 26 . 84
Table A.4 – Message 26 repeater command IDs . 84
Table A.5 – EPV configuration . 85
Table A.6 – EPV query. 86
Table A.7 – Property identifiers for use with EPV – Basic system parameters . 87
Table A.8 – Property identifiers for use with EPV – General repetition parameters . 88
Table A.9 – AES key configuration . 89
Table A.10 – RFS configuration . 90
Table A.11 – RFS query . 91
Table A.12 – RMF configuration . 92
Table A.13 – RMF query . 93
Table A.14 – RA1 configuration . 94
Table A.15 – RA1 query . 95
Table A.16 – RA2 configuration . 96
Table A.17 – RA2 query . 98
Table A.18 – RA3 configuration . 99
Table A.19 – RA3 query . 100
Table A.20 – RA4 configuration . 101
Table A.21 – RA4 query . 102

– 6 – IEC 62320-3:2015  IEC 2015
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
MARITIME NAVIGATION AND
RADIOCOMMUNICATION EQUIPMENT AND SYSTEMS –
AUTOMATIC IDENTIFICATION SYSTEM (AIS) –

Part 3: Repeater stations –
Minimum operational and performance requirements –
Methods of test and required test results

FOREWORD
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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 62320-3 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
80/744/FDIS 80/752/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 in the IEC 62320 series, published under the general title, Maritime
navigation and radiocommunication equipment and systems – 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 website 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.
– 8 – IEC 62320-3:2015  IEC 2015
INTRODUCTION
Chapter V of the 1974 SOLAS Convention requires mandatory carriage of Automatic
Identification System (AIS) equipment on all vessels constructed on or after 01 July 2002.
Implementation for other types and sizes of SOLAS Convention vessels was required to be
completed not later than 31 December 2004.
SOLAS Chapter V, Regulation 19, section 2.4.5 states that AIS shall:
a) provide automatically to appropriate equipped shore stations, other ships and aircraft
information, including ship's identity, type, position, course, speed, navigational status and
other safety-related information;
b) receive automatically such information from similarly fitted ships;
c) monitor and track ships; and
d) exchange data with shore-based facilities.
In addition, the IMO Performance Standards for AIS states that:
• The AIS should improve the safety of navigation by assisting in the efficient navigation of
ships, protection of the environment, and operation of Vessel Traffic Services (VTS), by
satisfying the following functional requirements:
1) in a ship-to-ship mode for collision avoidance;
2) as a means for littoral States to obtain information about a ship and its cargo; and
3) as a VTS tool, i. e. ship-to-shore (traffic management).
• The AIS should be capable of providing to ships and to competent authorities, information
from the ship, automatically and with the required accuracy and frequency, to facilitate
accurate tracking. Transmission of the data should be with the minimum involvement of
ship's personnel and with a high level of availability.
The provision of Shore Based AIS will be necessary to attain the full benefit of the SOLAS
Convention requirements.
This standard provides the minimum operational and performance requirements, methods of
test and the required test results for AIS repeater stations. The testing is divided into two
parts, the logical tests and the transceiver tests. These are captured in Clause 6 and Clause 8
respectively.
MARITIME NAVIGATION AND
RADIOCOMMUNICATION EQUIPMENT AND SYSTEMS –
AUTOMATIC IDENTIFICATION SYSTEM (AIS) –

Part 3: Repeater stations –
Minimum operational and performance requirements –
Methods of test and required test results

1 Scope
This part of IEC 62320 specifies the minimum operational and performance requirements,
methods of testing and required test results for AIS repeater stations, compatible with the
performance standards adopted by IMO Res. MSC.74 (69), annex 3, Universal AIS. It
incorporates the technical characteristics of non-shipborne, fixed station AIS equipment,
included in Recommendation ITU-R M.1371 and IALA Recommendation A-124. Where
applicable, it also takes into account the ITU Radio Regulations. This standard takes into
account other associated IEC International Standards and existing national standards, as
applicable.
This standard is applicable for AIS repeater stations. It does not include specifications for the
display of AIS data on shore.
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, Maritime navigation and radiocommunication equipment and systems – General
requirements – Methods of testing and required test results
IEC 61162-1, Maritime navigation and radiocommunication equipment and systems – Digital
interfaces – Part 1: Single talker and multiple listeners
ITU-R Recommendation M.585, Assignment and use of identities in the maritime mobile
service
ITU-R Recommendation M.1084, 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, Technical characteristics for a universal shipborne
automatic identification system using time division multiple access in the VHF maritime mobile
band
ITU-T Recommendation O.153, Basic parameters for the measurement of error performance
at bit rates below the primary rate
ITU Radio Regulations, Appendix 18

– 10 – IEC 62320-3:2015  IEC 2015
3 Symbols and abbreviations
AES Advanced Encryption Standard
AIS Automatic Identification System
AtoN Aids To Navigation
BER Bit Error Rate
BFO Beat frequency oscillator
BIIT Built-In Integrity Tests
BT Bandwidth Time product
COG Course Over Ground
CS Carrier Sense
CSTDMA Carrier Sense Time Division Multiple Access
DAC Digital Area Code
dBc Decibel-carrier
dBm Decibel-milliwatts
EUT Equipment under test
FATDMA Fixed Access Time Division Multiple Access
FI Function Identifier
FIFO First in, first out
GNSS Global Navigation Satellite System
IALA International Association of Marine Aids to Navigation and Lighthouse
Authorities
ITDMA Incremental Time Division Multiple Access
IMO International Maritime Organization
ITU International Telecommunication Union
kn Knots
MMSI Maritime Mobile Service Identity
NavStatus Navigational Status
NM Nautical Mile
NRZI Non-Return to Zero Inverted
PER Packet Error Rate
Pc Carrier Power
PI Presentation Interface
PPS Pulse(s) Per Second
RATDMA Random Access Time Division Multiple Access
RSSI Received Signal Strength Indication
Rx Receive
AIS-SART Search And Rescue Transmitter
SO Self-Organizing
SOG Speed Over Ground
SOTDMA Self-Organizing Time Division Multiple Access
TDMA Time Division Multiple Access
Tx Transmit
UTC Coordinated Universal Time

VCO Voltage controlled oscillator
VDL VHF Data Link
VHF Very High Frequency
VSWR Voltage Standing Wave Ratio
VTS Vessel Traffic Services
4 Functional requirements for a repeater station
4.1 General
Types of repeater stations
AIS repeater stations are designed to retransmit VDL messages in one or several steps to
extend the receiving range in areas with impaired VHF coverage. Careful consideration needs
to be taken not to overload the VDL with repeated messages, considering the additional load
repeated messages generate. The AIS environment may also contain one or more repeaters.
A repeater station is a store and forward repeater process.
A repeater station is a non-controlling station on the VDL.
The repeater station can be one of two types.
Type 1:
• Radio requirements as per the AIS base station requirements
• A dedicated repeater station is a Type 1 device
Type 2:
• Radio requirements as per the AIS AtoN station requirements
• Restricted repeater capability
• Suitable for areas with low AIS activity only
These two types of repeater functions can be implemented in three different ways:
• As a dedicated repeater station (Type 1)
• As an internal process of an AIS Base Station (Type 1)
• As an internal process of an AIS AtoN device (Type 2)
Repeating operation
(See 6.2.1)
Modes of repeating operation
The repeater station is designed for independent operation in autonomous and assigned
mode. No polled mode is allowed.
Message by message repeating
Each received message that shall be repeated is internally allocated for transmission using
RATDMA, ITDMA, or FATDMA as supported and configured.
Message rescheduling
This mode is only applicable for scheduled position reports.

– 12 – IEC 62320-3:2015  IEC 2015
Received messages shall be analysed and the repeater station shall reschedule
transmissions using an ITDMA schedule.
The repeater station may reschedule repeated messages using a reporting interval different
from the original interval, depending on configuration.
Synchronisation
(See 6.2.4)
The repeater station shall primarily use an internal source for UTC direct synchronisation.
The repeater station can synchronise on any AIS station that has direct UTC (otherwise
known as UTC indirect). The repeater station shall have UTC direct, or UTC indirect and only
transmit when sync state is 0 or 1.
Access to the VDL
Means of access
Access to the VDL can be by using pre-configured transmission slots. Pre-configured
transmission slots shall in this case be reserved by Message 20 from a base station.
If pre-configured slots are not available, RATDMA may be used for transmission.
A repeater station shall use as a minimum RATDMA, ITDMA and FATDMA to allocate and
pre-announce transmissions.
The repeater station needs to take into account all received Message 20s. It shall respect slot
reservations. If a base station reserves slots for the repeater station, the repeater station shall
be configured to use FATDMA.
CSTDMA is not suitable for repeater stations and not permitted because of:
• slot start delay;
• no protection from collision with Class B CS units;
• only one slot messages;
• intentional slot reuse is not allowed.
RATDMA and FATDMA access scheme
(See 6.3.1, 6.3.2)
The repeater station shall not change the data content of the message, but shall change the
SOTDMA communication state or ITDMA if relevant. The repeater station shall change the
SOTDMA communication state as indicated in Table 1.
Table 1 – SOTDMA communication state of received station
Received parameter Transmit parameters
Synch state Change to Synch State of repeater station
Slot time out Set to zero
Slot offset Set to zero
The repeater station shall change the ITDMA communication state as indicated in Table 2.

Table 2 – ITDMA Communication state of received station
Received parameter Transmit parameters
Synch state Change to synch state of repeater
Slot increment Set to zero
Number of slots Set to zero
Keep flag Set to FALSE ( = 0)
ITDMA access scheme
(See 6.3.3)
The repeater station shall not change the data content of the message, but shall change the
SOTDMA communication state or ITDMA as relevant. The repeater station shall change the
SOTDMA or ITDMA communication state to an ITDMA communication state as described in
Table 2. When using ITDMA to reschedule refer to Table 3.
If ITDMA is used and the repeater station receives a Message 1 that shall be repeated, the
repeater station shall change the message ID from 1 to 3 to all ITDMA access scheme.
Table 3 – ITDMA communication state of received station with rescheduling
Received parameter Transmit parameters
Synch state Change to synch state of repeater station
Slot increment Offset set to next transmission slot
Number of slots As required for next repeated message
Keep flag Set to FALSE ( = 0)
ITDMA can be used to schedule transmissions that originate from different stations.
When using ITDMA reservations, the selection interval shall be 150 slots. Set the ITDMA
communication state at time of transmission to the next scheduled transmission.
Configuration
(See 6.1.3)
Initial configuration shall be possible using the presentation interface of
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