Rescue beacon manufacturer Ocean Signal brought out the new ATB1 Class B AIS Transponder at METS, incorporating what the company is calling its superior SOTDMA access scheme.


Designed as an aid to collision-avoidance, the device is said to provide a significant advantage in navigational safety, giving Captains the peace of mind that their vessel will be seen day or night and no matter the weather. The new AIS unit uses the SOTDMA (Self Organised Time Division Multiple Access) scheme to provide this enhanced navigational safety. This complex AIS technology ensures increased priority for position reports with no loss or delay of transmission.

Using this advanced SOTDMA access scheme sets the ATB1 apart from CSTDMA (Carrier Sense Time Division Multiple Access) class B products available. Indeed, this new Class B unit has the same AIS transmission priority as a class A unit.

The ATB1 also has a faster reporting rate and higher output power than CSTDMA class B units. It sends AIS transmissions every 5 seconds instead of the traditional maximum two transmissions per minute, and uses 5W output power instead of 2W.

Other notable features include the ability to automatically upload vessel information such as name, call sign, type and dimensions, as well as the MMSI, directly from Ocean Signal’s user-friendly mobile app or website via WiFi. Once this information has been uploaded, it remains stored in the unit’s non-volatile memory even if powered down for long periods of time.

Superyacht Technology News met with the Ocean Signal team at METS last week to interview them about the new product… find out more in our METS Summary edition, out 4th Dec!