AtoN AIS Akari

Zeni Lite introduced the world’s first AIS unit for AtoN, the Akari-AIS-400, at the 2002 IALA Conference in Sydney. Since then, its AIS AtoN systems have been deployed globally. The company pioneered several innovations, including the first FATDMA AtoN AIS transponder, AIS installations on buoys, lighthouses, and light-beacons, remote monitoring of AtoN via AIS, and AIS-based weather and tidal broadcast stations. In 2005, Zeni Lite launched the Akari-100 with RATDMA/FATDMA options and support for meteorological and hydrological data. The Akari-1D and Akari-3D followed in 2008, marking further technological advancement.

Zeni Lite has introduced new Akari AIS AtoN models, which are more compact and energy-efficient than previous versions. The Akari-1/1S and Akari-3/3S correspond to IEC 62320-2 Type 1 and Type 3 standards, respectively. Beyond standard compliance, these units feature enhanced capabilities, including an extra circuit board for monitoring lantern and power supply status, sending addressed messages, and broadcasting meteorological and hydrological data.

Message 21, as defined by ITU-R M.1371, is used by AIS AtoN to transmit key navigational data to vessels. It includes the AtoN identity, type, position, and a digital flag indicating if a floating AtoN is off its intended location. Akari AIS AtoN units broadcast this message at configurable intervals. As e-Navigation advances under IMO and IALA, Message 21 is expected to play an increasingly vital role in maritime safety and efficiency.

Message 6, as defined by ITU, is an addressed binary message used for data transmission between AIS stations. Akari utilizes this format to report detailed status information about its lantern and power supply. The MSG6 format is compatible with Zeni Lite and GLA systems per IALA Recommendation R0126. Monitoring of AtoN AIS sites can be handled by the authority’s own center or delegated to a VTS or similar facility. AIS enables efficient data transfer, allowing quick detection of faults and improving AtoN service availability.

Message 8, as defined by ITU, is a broadcast binary message intended for multiple users. The IMO version of Message 8 is used to transmit meteorological and hydrological data. Akari units can broadcast this data at configurable intervals.
To collect such data, external sensors are required. Zeni Lite offers complete systems, including a unique GPS-based sensor that measures wave height, period, and direction using patented software. However, wave data accuracy may be affected by buoy movement.
Received Met-Hydro data from Akari can be displayed on ECDIS, radar, or a separate ENC display. The Akari unit operates within a broader AIS AtoN and AIS base station network.

The new products operate on 12-VDC or 24-VDC, offering improved energy efficiency and reliability. Limiting input voltage to 32-VDC enables a robust RF transmitter and power system design. In FATDMA mode, with Message 21 sent every 3 minutes, power consumption remains below 1.0 Ahr/day. If other voltages are required, a converter is used.

The selection of an appropriate Akari product depends on the required service, existing AIS infrastructure, and occasionally administrative factors related to base station networks. The information provided here serves as general guidance; for tailored advice, consult Zeni Lite offices or distributors.