The Complementarity of this project with others within the ambit of INTERREG III-B, namely the CLIMARCOST -Meteo-Oceanographic Data Monitoring System, whose partnership comprises the same entities of the MACAIS, enables the sailors to get information via transponders by establishing connections between the Operational Centres of CLIMARCOST and MACAIS. This on-line information is very relevant since it is about the maritime agitation and meteorological parameters to be gathered by different wave recorder stations on the waters of the 3 Regions. 

 

These and other A.I.S. Safety Messages are transmitted to the ships via on-board A.I.S., through one or more base stations. 

 

This meteo-oceanographic feature as well as other radio help systems connected with the A.I.S. common information will allow a meaningful increase in safety and efficiency in the set of sea activities and in those related to coasteal areas (tourism, sedimentary dynamics, coast planning, port and coastal protection infrastructures ).

A.I.S. Network Architecture:

To install the 3 shore Stations Networks in the archipelagos there was a need for resorting to a deep survey performed by the Hydrographical Institute of Portugal.
The Architecture case for Madeira was chosen as example in this diagram. It gives us a general idea of the A.I.S. system focusing on its constituent equipment on the different islands.

Shore  Stations, Logic Units and Control Centres are interconnected by the network and are supported by different data base.
The function of the Unit Logic is to follow-up the good performance of the A.I.S. equipment, assuring the data integrity and transmitting the information to the centres of the different Port Authorities. Besides that, it configures the Physical Shore Stations, detects any alterations in the service and communicates them to the responsible bodies.

The function of the A.I.S. Control Station is to follow-up the good performance of the A.I.S. network, supervising the respective land-based stations and logic units. It also has to assure the data integrity, transmit the information to the different Port Authorities. Besides that, it configures the Physical Shore Stations, detects any alterations in the service and communicates them to the responsible bodies.

Shore Stations:

An A.I.S. Shore Station is basically constituted by a transponder, a VHF aerial, a GPS aerial, a local control unit for the management and control of the physical Shore Station, one switch TCP/ IP, protection against lightening and other nature damages and a UPS unit with capacity to supply the A.I.S.  physical Shore Station for 3 hours after a power stop;

Physical Shore Station Network :

Given that the A.I.S. works in VHF units, the orographic obstacles can make it difficult to spread frequencies in some directions.
Thus, line-of-sight coverage diagrams were calculated from each A.I.S. Shore Station in order to confirm each station’s coverage area.
It must be stressed that these diagrams were obtained considering the line of sight propagation, but, in fact, the VHF waves suffer considerable alterations in their trajectory due to atmospheric refraction, which allows them to round the obstacles.
According to the table bellow, the total of 20  A.I.S. Shore Stations for 3 Regions are enough to cover practically all coastal areas in between the  shoreline when at a minimum of 20 miles away. Assuming that the on-board aerials have a height of 4 meters, we reached the following positive results, which show the good expected coverage rate.