Marine

The Global Positioning System (GPS) has altered the way the world operates. This is especially true for marine operations, including search and rescue. GPS provides the fastest and most accurate method for mariners to navigate, measure speed, and determine location. This enables increased levels of safety and efficiency for mariners worldwide.

It is important in marine navigation for the ship's officer to know the watercraft position while in open sea and also in congested ports and waterways. While at sea, accurate position, speed, and heading are needed to ensure the ship reaches its destination in the safest, most economical and timely fashion that conditions will allow. The need for accurate position information becomes even more vital as the ship departs from or arrives in port. ship traffic and other waterway hazards make maneuvering more difficult, and the risk of accidents becomes greater.

Mariners and oceanographers are increasingly using GPS data for underwater surveying, buoy placement, and navigational danger location and mapping. Commercial fishing fleets use GPS to navigate to most favorable fishing locations, track fish migrations, and ensure compliance with regulations.
An improvement to the basic GPS signal known as Differential GPS (DGPS) provides much higher accuracy and increased safety in its coverage areas for maritime operations. Many nations use DGPS for operations such as buoy positioning, sweeping, and dredging. This enhancement improves harbor navigation.

Governments and industrial organizations allover the worlds are working collectively to develop performance standards for Electronic Chart Display and Information Systems, which use GPS and/or DGPS for positioning information. These systems are revolutionizing marine navigation and are leading to the substitution of paper nautical charts. With DGPS, position and radar data can be integrated and displayed on an electronic chart, forming the basis of the Integrated Bridge System which is being installed on commercial vessels of all types.

GPS is playing an ever more vital role in the management of maritime port facilities. GPS technology, joined with geographic information system (GIS) software, is key to the competent management and operation of automated container placement in the world's largest port facilities. GPS facilitates the automation of the pick-up, transfer, and placement process of containers by tracking them from port entry to exit. With millions of container shipments being positioned in port terminals annually, GPS has greatly reduced the number of lost or misdirected containers and lowered associated operation costs.

GPS information is embedded within a system recognized as the Automatic Identification System (AIS) transmission. The AIS, which is authorized by the International Maritime Organization, is used for vessel traffic control around busy seaways. This service is not only very important for navigation, but is more and more used to bolster the security of ports and waterways by providing governments with greater situational consciousness of commercial vessels and their cargo.

AIS uses a transponder system that operates in the VHF maritime band and is capable of communicating ship to ship as well as ship to shore, transmitting information relating to ship identification, geographic location, vessel type, and cargo information -- all on a real-time, completely automated basis. Because the ship's GPS position is embedded in these transmissions, all essential information about vessel movements and contents can be uploaded automatically to electronic charts. The safety and security of vessels using this system is significantly enhanced.

Finally, with the modernization of GPS, mariners can look forward to even better service. In addition to the current GPS civilian service, the United States is committed to implementing two additional civilian signals. Access to the new signals will mean increased accuracy, more availability, and better integrity for all users.