TYPE 1 AND TYPE 3

AUTOMATIC IDENTIFICATION SYSTEM

The VegaAIS transponder is an AIS ATON Station and part of the Automatic Identification System (AIS) operating in the VHF maritime band. The VegaAIS transponder will provide broadcast information of the location and operation of an Aid To Navigation to vessels and base stations receiving AIS messages. The transponder can provide monitoring information and relay Meteorological / Hydrological information as part of the overall AIS system.

The AIS system uses time division multiple access (TDMA) to transmit messages. The VegaAIS Type 1 uses Fixed Access TDMA (FATDMA) where time slots are reserved by a local AIS base station. The VegaAIS Type 3 can either use FATDMA or Random Access TDMA (RATDMA) where communication slots are not required to be reserved by a AIS base station. In the Type 3 unit each AIS message can be configured to transmit as a FATDMA or RATDMA message.

In addition to monitoring information, the VegaAIS unit can transmit the details of up to three virtual ATON locations. The VegaAIS unit supports collision monitoring and “On Demand” operation of the ATON. A Type 3 unit is required in order to be able to receive the information to perform and report these features.