At the ITU World Radio communication Conference (WRC) in Geneva during October/November 1997, IMO requested that two maritime VHF channels be assigned for AIS. These were designated and a footnote was added to Appendix S18 of the ITU Radio Regulations titled “Table of Transmitting Frequencies in the VHF Maritime Mobile Band” as follows:-
“These channels (AIS 1 and AIS 2) will be used for an automatic ship identification and surveillance system capable of providing worldwide operation on high seas, unless other frequencies are designated on a regional basis for this purpose”
The channels allocated are:
- AIS 1 (161.975 MHz.)
- AIS 2 (162.025 MHz.).