How AIS works

GPS Positioning
"See around corners" connected to a chart system

The vessel's primary GPS receiver needs to be interfaced with the AIS and is used as the main positioning source. However, the AI80 also incorporates an "all-inview" GPS receiver which can be used as back-up for the primary GPS receiver. Easy installation The remotely installed transponder with separate display provides a simple installation solution, saving time and money.

Chart and Radar Interfacing

AIS can be interfaced to electronic charts or radar provided they support the AIS interface. When interfacing AIS to radar and chart plotters, AIS target information as position, heading course and speed becomes available to the mariner and increase reliability of navigation data from other vessels.

ARPA radar interface

By activating the interface to an ARPA radar, moving targets and operator selected "fixed points" can be displayed. Other vessels are then shown in real time on the chart, color coded depending on possibility for collision.

VHF data communication

Dedicated VHF frequencies are used for AIS data communication and the range is dependant on the height of the VHF antenna. In order to avoid interference with the ship's VHF voice communication, the AIS VHF antenna must beinstalled in accordance with IMO requirements. As the SOTDMA (Self Organized Time Division Multiple Access) protocol, which utilizes timeslots for transmission and reception of data is being used, an almost unlimited number of users may operate on the system at the same time without causing interference problems.