Automatic Identification System(AIS)

Automatic Identification System(AIS)

*Description:

The automatic identification system for ships adopts time-division multiple access technology in the very high frequency (VHF) mobile frequency band, automatically broadcasting and receiving static information, dynamic information, voyage information, and safety information of ships. Through information exchange, ship identification, collision avoidance, and navigation can be effectively completed to ensure the safety of ships. The International Maritime Organization (IMO) stipulates that ships of 300 gross tons or more on international routes and ships of 500 gross tons or more on domestic routes operated by convention countries are required to install AIS equipment in stages from July 1, 2002 to July 1, 2008.

The static information transmitted by ship borne AIS includes ship name, call sign, captain, ship width, IMO number, and ship type; Dynamic information includes ship position (latitude and longitude), heading, speed, navigation status, and other related information. Its operating distance is approximately 25 nautical miles, which means that through the AIS system, information about all other ships carrying AIS systems within a 25 nautical mile range of this ship, including their names, can be obtained; Is it sailing or anchoring; What is the heading; What is the speed of the ship. At the same time, AIS is not affected by visibility, rain, snow, and obstacles, greatly improving the ability of ships to coordinate and avoid each other.

*Objective:

1. Identify ships;

2. Assist in tracking targets;

3. Simplify and promote information exchange;

4. Provide auxiliary information to avoid collisions;

5. Reduce verbal mandatory ship reporting

*The significance of AIS system

1. Reduce investment in VTS and VHF-DSC construction;

2. The social benefits of AIS are to avoid ship collisions, reduce loss of life and property damage;

3. Solved the major problem of ship shore information transmission, achieved ship shore information networking and ship information sharing;

4. Promote the informatization project of transportation.

*Major function

1. Ship collision avoidance: AIS shipyards installed can automatically identify and exchange information with ships sailing in the waters of the Yangtze River estuary.

2. Maritime management: Continuous monitoring and management of static and dynamic information of ship navigation.

3. Enhance VTS function: AIS information is integrated into the VTS system to improve the recognition accuracy and information volume of ships, and extend the traffic management scope of ships in the Yangtze River estuary.

*AIS message content

AIS messages provide three types of data, including:

1. Ship static data, including ship name, call sign, MMSI, IMO, ship type, captain, ship width, etc;

2. Ship dynamic data, including longitude, latitude, bow direction, track direction, speed, etc;

3. Ship voyage data, including ship status, draft, destination, ETA, etc.

*AIS system service content:

1. Services provided for ships

Water traffic dynamics and traffic guidance;

Navigation warnings, navigation notices, and traffic control information;

Factors affecting ship navigation, such as meteorological, hydrological, and navigational information;

Answer the request for help from the opposite shore of the shipyard.

2. Services provided to the maritime department

Ship dynamic and static information;

Relative to the position of the waterway;

The location and intention of surrounding vessels;

Publish navigation warnings, navigation notices, and traffic control information.

3. Social Information Services

It provides services for ships, shipping companies, shipping departments, governments, ports, ecology, rescue, marine and atmospheric, research and statistics, public access, VTS, counter-terrorism, etc. through C/S and B/S models.