New Products
AtoN AIS Products
Akari-1 and Akari-3
Various Aluminium Lighthouse & Beacon
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Akari-1 & Akari-3 Series AIS AtoN Units Offer Versatility, Small Size, and Low Power Drain |

Zeni Lite - Heritage and Experience in AIS AtoN
Zeni Lite launched and demonstrated the world's first AIS unit specifically designed for Aids to Navigation, the Akari-AIS-400 at the IALA Conference in Sydney in March 2002. Since then our AIS AtoN systems have been installed in Europe, Asia, the Americas, the Middle East, and African continent.
Zeni Lite was also the first to announce an FATDMA AtoN AIS transponder, the first to install AtoN AIS on buoys, on lighthouses and on light-beacons, the first to monitor Aids to Navigation over an AIS link, and the first to install and commission AIS weather and tidal message broadcast stations at AtoN sites.
The Akari-100 product, released in 2005 brought a new standard of capability, with a choice of RATDMA or FATDMA operation and the ability to broadcast meteorological and hydrological data.
Now Zeni Lite announces a new AIS AtoN series, including Akari-1, Akari-1D, Akari-3, and Akari-3D.
The New Akari-1 and Akari-3 Series AIS AtoN Units
Following the success of the Akari-100 AIS AtoN, Zeni Lite is pleased to announce the new Akari-1 and Akari-3 AIS AtoN products, which are smaller and use less power than their predecessor.
The names reflect the types of AIS AtoN defined in the IEC 62320-2 test standard, Akari-1 being an IEC Type 1 unit, and Akari-3 being an IEC Type 3 unit.
Akari-1D and Akari-3D offer additional features over the minimum requirements for IEC Type 1 and Type 3 respectively. These products contain an additional circuit board with sensing, computing, and memory components to monitor lantern and power supply operation, send addressed messages with monitoring data, and broadcast meteorological and hydrological messages.
AIS Message 21 - For Navigation
AIS Messages are defined by ITU-R M.1371, and Message 21, "Aids to navigation Report", is for broadcasting by AIS AtoNs to provide navigation information for use by shipping. As well as the identity of the AtoN, the type of AtoN, and its position, this message carries a digital flag to indicate if a floating AtoN is off position. All the Akari AIS AtoN units broadcast Message 21 at an interval which is configurable by the authority.
Message 21 will increasingly be an important part of e-Navigation, now being developed by IMO and IALA.
Monitoring of AtoN Lantern and Power Supply - Message 6
ITU defines Message 6 as an addressed binary message, used for sending of data from one AIS station to another. The Akari-1D and Akari-3D use Message 6 to carry extensive information on the operational status of a lantern and power supply at the Akari unit's location.
The AtoN authority may have its own monitoring centre, or may assign the monitoring task to a VTS centre or other existing facility. Whatever the location, the monitoring data from each AtoN AIS site can be easily transferred to the required point via the AIS network. Early indication of fault or failure of a lantern or power supply allows the authority to respond rapidly, increasing the availability of the AtoN service.
Meteorological and Hydrological Report - Message 8
Message 8 is defined by ITU as a broadcast binary message, meaning that it is intended for multiple users. IMO has defined one version of Message 8 for carrying meteorological and hydrological data. Akari-1D and Akari-3D can broadcast this message at intervals set during configuration of the unit.
External sensors are, of course, needed for obtaining most such meteorological and hydrological data, and Zeni Lite can provide complete systems.
The Akari-1D and Akari-3D products can measure wave height, period and direction using GPS receiver and patented unique software processes as option, and add this to the broadcast meteorological and hydrological messages, so no external sensor is needed. Users should note that the accuracy of the wave data is affected by buoy motion.
The data display of the Met-Hydro data received from Akari-1D or Akari-3D may be on the ECDIS or radar, or on a separate ENC display. At right is an example of parts of an ENC display, showing a portion of the ENC with the AIS AtoN, and the Met-Hydro data display window. This Akari unit is part of an extensive AIS AtoN and AIS base station network.
Input Power
The new products use a nominal supply voltage of 12-VDC. The advantage lies in two areas, energy efficiency and reliability. Limiting the maximum input voltage to 16-VDC permits a robust design of RF transmitter and power system, resulting in the highest reliability. The other advantage is power drain. Operating in FATDMA mode, with Message 21 sent every 3 minutes, power drain is less than 0.7 Ahr per day. If a different supply voltage must be used, a voltage converter is employed.
Recommended Applications
The choice of the most suitable Akari product for a given application is influenced by the service required, the existing AIS infrastructure, and sometimes by administrative arrangements for base station networks. The following is for guidance only. Zeni Lite offices and distributors can provide additional advice.
AKARI-AWS
AIS Weather Station
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- Fixed or floating installation
The Akari-AWS system is suitable for installation on buoys or fixed structures. Power drain by both the sensor package and the AIS module is minimised by special hardware and software. Exact power drain depends on the AIS message frequency. Zeni Lite will be pleased to prepare an energy budget based on your data requirements.
When an aid to navigation is used as the platform, all the benefits of the Akari-1D or Akari-3D aids to navigation transponder are also available, both for navigation safety and aids to navigation management.
Meteorological and Hydrological Sensors
The Akari-AWS and Akari-DIU system has been integrated to different manufacturers’ Meteorological and Hydrological sensors, making it a trully universal compatible product.


Sensors:Akari-AWS may be fitted with the following sensors.
- Group 1 sensors
・ Wind speed
・ Wind direction
・ Barometric pressure
・ Air temperature
・ Relative humidity - Group 2 sensors
・ Current speed
・ Current direction
・ Sea surface temperature
・ Water level [tidal height]
・ Wave data
Group 1 sensors may be installed easily in almost any location.
Group 2 sensors may require special consideration. Consult Zeni Lite to discuss your particular needs.
Or a combination:
An Electronic Navigation Chart identifying a number of Lighthouses & Resilient Beacons (Spar Buoys) fitted with Meteorological and Hydrological (Weather) Sensors broadcasting Message 8.


Zeni Lite Akari-1D or Akari-3D AtoN AIS unit - Single-line diagram installation example.
Typical installation with lantern and other equipment such as meteorological or tidal sensors, or another AtoN system
