# Commission Implementing Regulation (EU) 2019/838 of 20 February 2019 on technical specifications for vessel tracking and tracing systems and repealing Regulation (EC) No 415/2007, Division 3.2: Scope

Extent: E+W+S+N.I.

The AIS is a ship-borne radio data system, exchanging static, dynamic and voyage related vessel data between equipped vessels and between equipped vessels and shore stations. Ship-borne AIS stations broadcast the vessel's identity, position and other data in regular intervals. By receiving these transmissions, ship-borne or shore-based AIS stations within the radio range can automatically locate, identify and track AIS equipped vessels on an appropriate display like radar or electronic chart display systems such as the Inland Electronic Chart Display and Information System (Inland ECDIS) as defined in Commission Implementing Regulation (EU) No 909/2013. AIS is intended to enhance safety of navigation in ship-to-ship use, surveillance (VTS), Vessel Tracking and Tracing, and calamity abatement support.
AIS mobile stations are divided into following types:
a)) Class A mobile stations to be used by all sea going vessels falling under carriage requirements of Chapter V of SOLAS convention;
b)) Inland AIS mobile station, having full Class A functionality on VHF Data Link level, deviating in supplementary functions designed for the use by inland vessels;
c)) Class B SO/CS mobile stations with limited functionality which may be used by vessels not falling under carriage requirements for Class A or Inland AIS mobile stations;
d)) AIS shore stations, including AIS base stations and AIS repeater stations.
The following modes of operation can be distinguished:
a)) ship-to-ship operation: all AIS equipped vessels are able to receive static and dynamic information from all other AIS equipped vessels within the radio range;
b)) ship-to-shore operation: data from AIS equipped vessels can also be received by AIS shore stations connected to the RIS centre where a traffic image (Tactical Traffic Image and/or Strategic Traffic Image) can be generated;
c)) shore-to-ship operation: voyage and safety related data from shore to vessel can be transmitted.
A characteristic of AIS is the autonomous mode, using self-organised time division multiple access (SOTDMA), without any need for an organising master station. The radio protocol is designed in a way that vessel stations operate autonomously in a self-organised manner by exchanging link access parameters. Time is divided into one minute frames with 2 250 time slots per radio channel which are synchronised by GNSS UTC time. Each participant organises its access to the radio channel by choosing free time slots considering the future use of time slots by other stations. There is no need for a central intelligence controlling the slot assignment.
An Inland AIS mobile station consists in general of the following components:
a)) VHF transceiver (one transmitter, two receivers);
b)) GNSS receiver;
c)) data processor.
Universal ship-borne AIS, as defined by IMO, ITU and IEC, and recommended for the use in inland navigation uses SOTDMA in the VHF maritime mobile band. AIS operates on the internationally designated VHF frequencies AIS 1 (161,975 MHz) and AIS 2 (162,025 MHz) and can be switched to other frequencies in the VHF maritime mobile band.
To serve the specific requirements of inland navigation, AIS has to be further developed to the so called Inland AIS while preserving compatibility with the maritime AIS.
Vessel Tracking and Tracing systems in inland navigation shall be compatible with AIS Class A mobile stations, as defined by IMO. Therefore, Inland AIS messages shall be able to provide the following types of information:
a)) static information, such as official vessel number, call sign of vessel, name of vessel, type of vessel;
b)) dynamic information, such as vessels position with accuracy indication and integrity status;
c)) voyage related information, such as length and beam of convoy, dangerous cargo on board;
d)) inland navigation specific information, such as number of blue cones/lights according to ADN or ETA at lock/bridge/terminal/border.
For moving vessels the update rate for dynamic information on tactical level shall be between 2 and 10 seconds. For vessels at anchor it is recommended to have an update rate of several minutes, or an update triggered when information is amended.
Inland AIS mobile station does not replace, but supports navigational services such as radar target tracking and VTS. Inland AIS mobile station provides an additional input for navigational information: its value added is to provide means of surveillance and tracking of vessels equipped with Inland AIS. The position accuracy derived from Inland AIS mobile station using the internal (uncorrected) GNSS is typically above 10 metres. When the position is corrected using DGNSS from either maritime beacon differential correction service, AIS Message 17 or EGNOS (SBAS) the accuracy is typically below 5 metres. Due to their different characteristics, Inland AIS mobile station and radar complement each other.

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Source: https://www.legislation.gov.uk/eur/2019/838/annex/division/3/division/3.2 (the official version)
Page: https://openlegislation.uk/eu-regulation-2019-838/annex/division-3/division-3.2
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.