AIS system makes ship position report more accurate and fast. Broadcast AIS can automatically and continuously send ship navigation information or insert ship and voyage information according to the query requirements, and then send it to the reporting station through the wireless communication network and then to the calculation center. The calculation center will establish a database of all ships according to the system requirements, and analyze and process the static data of ships, electronic charts and meteorological data according to the requirements of users, so as to provide ship information and search and rescue for the search and rescue department. At present, BLM-Shipping provides applications and services based on AIS system, receives AIS data of ships, and provides intuitive ship positioning, real-time dynamic query and historical trajectory tracking services. Therefore, it has a broad application prospect in maritime management, has the ability to supervise ship traffic management, has the ability to manage transport fleets, has the ability to pilot ships in and out of ports, and has the ability to search and rescue ships in distress, which is of great help to navigation early warning and meteorological information of ships at sea.
Navigation mark telemetry and remote control system based on AIS system
AIS navigation mark telemetry and remote control system consists of automatic navigation mark equipment and AIS transponder. Compared with the existing navigation mark telemetry and remote control system, it has the following advantages: it does not need to apply for telemetry and remote control channels, and directly uses AIS international dedicated channels CH87B and CH88B to transmit data; The construction of special communication network can be omitted, and only navigation AIDS and AIS transponders need to be configured; AIS's open system interconnection mode enables it to access the Internet conveniently, and enables the competent department of navigation AIDS to monitor and manage navigation AIDS facilities through the Internet. Navigation information can also be applied in a way similar to "ship-to-ship". IS can also be used as a virtual navigation sign. Virtual navigation mark can be a virtual navigation mark facility or a virtual navigation mark system. AIS navigation mark telemetry and remote control system has the advantages of less equipment, low investment cost, short construction period, powerful function, convenience and easy operation.
Application of AIS system in real-time release of hydrometeorological information
The format of hydrometeorological information generally includes average wind speed, wind direction, water level, water temperature, air temperature, speed and direction of different concentrations, and tidal information. If it is registered in ILA (International Association of Lighthouse Authors of Navigation Aids) in advance, it can be applied internationally.
Application of AIS system in VTS
1) to enhance the ship identification ability. For data such as ship position, ship heading and ship speed to the ground, radar obtains the average value of historical tracks, while AIS obtains instantaneous data, so the accuracy of AIS is higher than that of radar. Radar can only obtain the dynamic information of the ship, and the phenomenon of tag exchange or tracking loss often occurs in the area where two ships cross or have high density. The information transmitted by AIS includes not only the dynamic information of the ship, but also the static information, and there is almost no data loss.
2) Improve the dynamic tracking ability and expand the tracking range. AIS data can be received by other AIS stations and relay stations, and ship information can be received and tracked within the maximum receiving range of VHF wireless communication frequency.
High accuracy. The accuracy of ship position data provided by GPS/DGPS is less than 5m, which greatly improves the tracking resolution and accuracy, and the tracking vector stability time is short. When the delay of radar data processing is about 20 antenna scanning periods, it is about 1.5 min. However, A IS information tracking can directly obtain the dynamic data of the target for identification, which has no stable time and high tracking reliability. The transmitted data is not affected by weather and sea conditions, and is used by international dedicated channels and.
3) Integrate and supplement VTS functions. The information provided by ARPA (automatic radar p lotting aid) is very limited, and it is impossible to identify the intentions of other ships, especially in narrow waterways, bends of waterways, behind islands, waters with high ship density, and when encountering bad weather and sea conditions. The automatic tracking function has the problems of tracking by mistake, losing the target, and even failing to detect the target, and with the increase of the observation distance, the measurement accuracy and resolution of the target will decrease. Because AIS uses VHF band as the wireless communication link, its ability to resist the interference of waves, rain and snow is better than that of ordinary radar, and its ability to capture and track targets is more effective, and the communication link of AIS can maintain a good connection. It can make up for the weakness of radar in bad weather conditions. Radar waves can only travel in a straight line. When a ship is blocked by other ships or tall objects, it forms a blind spot of radar, and AIS can also make up for the shortage of radar.
4) VTS based on AIS system has good cost performance. Because AIS has good remote control performance, a control platform can remotely control multiple base stations, a few control stations and a large number of base stations can cover a wide area, and the investment of an IS base station is much lower than that of a radar station. In ports with low traffic density, ships equipped with AIS can form an "unmanned VTS" without shore stations. In busy ports, AIS will reduce the workload of VTS operators and improve their work efficiency in tasks such as traffic management and information service.