How the automatic identification system works
www.amsa.gov.au › safety-navigation › navigationThe automatic identification system (AIS) works automatically and continuously, regardless of where a vessel is located. There are two dedicated frequencies used for AIS: AIS 1 (channel 87B) AIS 2 (channel 88B). Each frequency is divided into 2250 time slots that are repeated every 60 seconds. The AIS units send packets of information which are transmitted in these time slots.
How AIS Works - Power & Motoryacht
www.powerandmotoryacht.com › electronics › how-ais-worksFeb 24, 2015 · The Automatic Identification System, or AIS, is a tracking system that uses transponders operating on two dedicated VHF radio frequencies to share data—including vessel name and type, position, speed, course, and rate of turn—between boats, and is updated frequently (transmission rates vary with vessel type and speed), as most of us know by now.
How AIS Works | Boating Mag
www.boatingmag.com › how-ais-worksOct 18, 2016 · How does the automatic identification system (AIS) work? A. AIS signals are transmitted from vessels through VHF radio frequencies. An icon appears on the navigation displays of craft equipped to receive AIS information, indicating the transmitting ship’s location.
HOW AIS WORKS - navcen.uscg.gov
navcen.uscg.govAIS normally works in an autonomous and continuous mode, regardless of whether it is operating in the open seas or coastal or inland areas. Transmissions use 9.6 kb GMSK FM modulation over 25 or 12.5 kHz channels using HDLC packet protocols. Although only one radio channel is necessary, each station transmits and receives over two radio channels to avoid interference problems, and to allow channels to be shifted without communications loss from other ships.