Appendix 1 Description of AIS
Clasification Society 2024 - Version 9.40
Statutory Documents - IMO Publications and Documents - Resolutions - Assembly - IMO Resolution A.1106(29) Revised Guidelines for fhe Onboard Operational Use of Shipborne Automatic Identification Systems (AIS) (Adopted on 2 December 2015) - Appendix 1 Description of AIS

Appendix 1 Description of AIS


1 In general, an onboard AIS (see figure 1) consists of:
  • - antennas;
  • - one VHF transmitter;
  • - two multi-channel VHF receivers;
  • - one channel 70 VHF receiver for channel management;
  • - a central processing unit (CPU);
  • - an electronic position-fixing system, Global Navigation Satellite System (GNSS) receiver for timing purposes and position redundancy;
  • - interfaces to heading and speed devices and to other shipborne sensors;
  • - interfaces to radar/Automatic Radar Plotting Aids (ARPA), Electronic Chart System/Electronic Chart Display and Information System (ECS/ECDIS) and Integrated Navigation Systems (INS);
  • - built-in integrity test (BIIT); and
  • - minimum display and keyboard to input and retrieve data.

With the integral minimum display and keyboard unit, the AIS would be able to operate as a stand-alone system. A stand-alone graphical display or the integration of the AIS data display into other devices such as INS, ECS/ECDIS or a radar/ARPA display would significantly increase the effectiveness of AIS, when achievable.

 2 All onboard sensors must comply with the relevant IMO standards concerning availability, accuracy, discrimination, integrity, update rates, failure alarms, interfacing and type-testing.

3 AIS provides:
  • - a BIIT running continuously or at appropriate intervals;
  • - monitoring of the availability of data;
  • - an error detection mechanism of the transmitted data; and
  • - an error check on the received data.

Figure 1 - AIS Components


The connection of AIS to external navigational display systems

4 The AIS can be connected either to an additional dedicated AIS display unit, possibly one with a large graphic display, or as an input to existing navigational system devices such as a radar display, ECS, ECDIS, or INS. Such system interconnection and data integration is recommended."

The connection of AIS to external portable navigational equipment

5 It is becoming common practice for pilots to possess their own portable navigational equipment, which they carry on board. Such devices can be connected to shipborne AIS equipment and display the targets they receive. Some Administrations require this connection to be provided at the bridge front.

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