Small fishing vessels account for more than 60% of total accidents according to the statistics on domestic marine casualties. And the range of vessels that have to be equipped with Automatic Identification System (AIS) is being enlarged as the 'Ship Safety Act' reinforced. Therefore, it is necessary to design and implement the customized AIS device and auxiliary functions.
In chapter 2 of this thesis, both domestic and international technology trends on AIS were described as were the results of a study that surveyed people who will actually use AIS technology. Based on results of technical trends and the survey, the necessity for a low priced AIS device and auxiliary functions was determined.
In chapter 3, standards for an AIS Class B system for fishing boats were presented. These were based on an analysis of existing domestic and international tech requirements. Also, described were the results of actual system design, main process module design, and auxiliary system design and implementation. The R&D efforts are summarized below.
A transceiver part containing two receiving channels and one transmitting channel was designed as part of AIS terminal design and implementation. CSTDMA, one of the international standards, was used for VHF telecommunication method.
The system design and implementation took into consideration security measures to alleviate potential backlash from fishing boat owners who have been concerned that introducing an AIS system to prevent maritime accidents could also reveal their fishing locations. First, the location information of the AIS equipped vessel is encrypted so that only related institutions and boats in the same fishing fleet can listen to the signals. Additionally, an encryption process module is attached, thus allowing the AIS terminal to transmit a non-encrypted AIS signal when one boat approaches the safety limit.
Second, a course recording module was designed and implemented so that maritime accident analysis and investigation could be assisted by the track data.
Third, a duty-free fuel management module based on smart card technology was added. This module compares and manages recorded track and filled fuel. With this module, clearer and more rational duty-free fuel management is expected to be realized.
In chapter 4, hardware and software test results were described showing how hardware performs and how the location information and encrypted information are received, processed and displayed on the vessel monitoring system and how well the auxiliary system functions are working.
As the test results showed, the hardware satisfied both domestic and international standards. The GPS information is well received and contained location information is confirmed to be set accordingly. Also, based on the received location information, transmission of current location information is confirmed and transmission of the non-encrypted standard vessel location information when a vessel approaches too closely is also confirmed. Also, confirmed are the replay function with track data stored on SD card by the course recording module and the display of the migration distance calculated by the duty-free fuel management module using GPS location information.
As an AIS system that both satisfies international standards and reflects the needs of potential users is successfully developed, voluntary participation of fishing boat owners is thought to be possible. With various auxiliary functions, the system will help with maritime accident prevention efforts, the safe navigation of all vessels along domestic coasts, and more efficient and integrated management for small boats. This new international standard based AIS system is expected to play a new and leading role in the domestic AIS system industry.
In the future, R&D on more auxiliary functions and systems that fit the unique domestic situation should be continued as well as efforts to improve the current AIS system for small fishing boats. Also, the channel overload issue that will occur on the VHF maritime mobile band when all small fishing boats are equipped with the AIS system has to be resolved in the future.