• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2001.10a
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• pp.19-25
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• 2001

At present the identification of vessels is still depending on the OOW (Officer Of Wateh) in VTS (Vessel Traffic Service), which is completed by radar, and also by the combination of VHF radio and VHF direction finder. However, with the development of port transportation and economic, this conventional way of identification can't satisfy more and more request for the information that the VTS needs from the vessels. In such a case, the AIS(Automatic Identification System) precept which is based on STDMA (Self-organized Time Division Multiple Access) technique is put forward by IMO (International Maritime Organization). AIS can automatically provide the information, including own ship's identification, type, position, course, speed, and other information to the appropriately equipped coast station and other ships. At the same time it can also automatically monitor and track the nearby ships similarly fitted with AIS. On the basis of describing the whole comprising and the format of transmission information of AIS, this paper mainly studies the key communication techniques in AIS, such as STDMA protocol, net synchronization and GMSK(Gaussian Minimum Shift Keying)technique, and so on. At last this paper briefly introduces the recommendation decided by IMO on forcing the sea-going ships to fixed with AIS equipments, and it continuos with the unexploited potential of AIS if it applies in VTS.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.14 no.4
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• pp.824-830
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• 2010

In order to prepare for increasing performance requirement for Differential Global Navigation Satellite System (DGNSS) services of International Maritime Organization (IMO) and International Association of Lighthouse Authorities (IALA), this paper focuses on design of network-based Automatic Identification System (AIS) reference station system that can perform the functionality of Differential Global Positioning System (DGPS) reference station in an AIS base station system. AIS base station receives the differential corrections from the DGPS reference station, and it is not a method for transmitting the received differential corrections to onboard AIS units, but it is a method for generating the optimized differential corrections for onboard AIS units in AIS coverage. Therefore this paper proposes an algorithm for generating the differential corrections at AIS reference station, and performs the performance assessment of the proposed algorithm based on DGPS correction data measured from a DGPS reference station. Finally this paper discusses the test results and efficiency of the proposed system.

• Proceedings of KOSOMES biannual meeting
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• 2006.11a
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• pp.75-83
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• 2006

The Automatic Identification System (AIS) will provide valuable navigational information to the coastal passenger ship to which RADAR did not cover until now. 112 skippers of coastal passenger ship who are using AIS plotter responded that the AIS is very useful to their safety and they are using the AIS effectively regardless of number of seafarers, ship's speed and navigation time. It is required that all coastal ships should install the AIS to improve the safety navigation in the coastal navigation area.

• Journal of Space Technology and Applications
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• v.2 no.2
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• pp.121-136
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• 2022

Automatic Identification System used in ship communication is required for marine control way, including monitoring of vessel operation in coastal and exchanging of information for safety navigation between them. But, it uses a very high frequency band of approximately 160 MHz, and at the same time, due to the curvature of Earth, there is a limit to the communication distance. Several demonstrations were made successfully over satellite, but not much work has been done yet through cube-satellite which has low-orbit at 500 km altitude. Here, we demonstrate a reception test of AIS (automatic identification system) receiver for a cube-satellites using software-defined radio (SDR). We collected AIS data from ship at port of Busan, Korea, using R8202T2 SDR and established to transmit them using Adam-Pluto and Matlab Simulink. The process of weakening the signal strength to a satellite was constructed using attenuator. Through above process, we demonstrated whether AIS data was successfully received from the AIS payload.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2001.10a
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• pp.765-768
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• 2001

A universal shipborne automatic identification system(AIS) uses self-organised time division multiple access(SOTDMA). The performance evaluation system of the SOTDMA algorithm for AIS is needed to implement it efficiently. This paper shows the method of designing it. Real ships access the VHF maritime mobile band but in this performance system, several ship objects access the shared memory. Real ships are designed as the object and the wireless communication channel is designed as the shared memory. This system shows several stations are assigned the transmission slot by the SOTDMA algorithm

• The Journal of Korean Institute of Communications and Information Sciences
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• v.36 no.5B
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• pp.530-538
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• 2011

In this paper, the feasibility of LEO(low earth orbit) satellite-based automatic identification system (SAT-AIS) for the coastal area of the South Korea is evaluated in the context of ship AIS transmission detection probability. We evaluate and compare AIS signal detection probability of ORBCOMM satellites and LEO-one satellites considering link budget, SOTDMA protocol and satellite's swath width. The simulation determines the total number of vessels served by those satellites according to satellite's swath width and thus, By simulation results, the ORBCOMM SAT-AIS system outperforms LEO-one SAT-AIS system. The suggested ORBCOMM based SAT-AIS system can be a solution to resolve the existing limited transmission distance problem of the conventional ship-to-shore AIS system.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2001.10a
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• pp.753-756
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• 2001

Automatic Identification System(ALS) employed SOTDMA for the multiple access method. In SOTDMA systems, slot reuse may result in discrimination or garbling. Especially Gaussian Minimum Shift Keying(GMSK) Co-Channel Interference(CCI) resulted from the slot reuse in the Aloha zone degrades the system performance such as capacity In this paper we introduce some useful techniques to cancel the CCI and discuss the methodology which is applicable to AIS-SOTDMA

• Journal of the Korea Institute of Information and Communication Engineering
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• v.15 no.12
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• pp.2590-2598
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• 2011

AIS(Automatic Identification System) is a key of maritime information system to prevent maritime accident through communication among any adjacent ship and to establish information base by fusing information collected from ships with other information. The AIS information includes various potential information, but it is not easy to use due to insufficiency storing and management. Furthermore, we need AIS transponders to acquire the information. In this paper, we propose the vessel positional information service using AIS and XML. We decode the AIS information from the NMEA-0183 encoding data and store the AIS information to the database and provide the access service in the internet using XML.

• Journal of the Korean Institute of Intelligent Systems
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• v.24 no.3
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• pp.310-315
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• 2014

The domestic maritime environment shows higher frequency of maritime accidents amidst greater traffic volume arising from increasing international seaborne trade and maritime leisure activities. To reduce such maritime accidents, there exist various kinds of safety navigation devices in the ship bridge aimed to mitigate burdens of navigators and support their accurate decision making. Amongst is the AIS considered very important, which is an automatic tracking system to assist understanding of the circumstances in the vicinity by receiving information of other ships and also sending its own; where the information contains errors initially, however, such wrong information is periodically transmitted, accordingly giving rise to hindrance sometimes in decision making by shore operators or ship navigators at sea. This study is to propose the error data and field management algorithm using fuzzy theory toward improving reliability and accuracy in ship related information received from AIS.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2006.10a
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• pp.63-70
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• 2006

Now AIS (Automatic Identification System) has been under full operation for ocean-going vessels, and it is expected not only to identify target ships but also to take collision avoidance using AIS information with Radar and ARFA information in restricted waters. AIS information is very useful not only for target identifications but also for taking collision avoidance, but OOW (Officer OF Watch-keeping) should take care of systematic observation of AIS because of miss-operation or malfunction of AIS. In this paper, we propose the application of Onboard Ship Handling Simulator with visual system displayed 3D scene added AIS performance such as blind areas of Island, microwave propagation, ok. and maneuvering simulation using TK models, applied real time AIS information and research the effectiveness of this system for ship handling in restricted waters, and discus the principal issues through the on board experiments. Conclusion will be expected that; 1) systematic observation of ASS information using visual scene simulator with AIS information will be effectively done, 2) observation compared with Radar and ARPA information will be also useful to make a systematic observation, 3) using the recording and replay function of simulation will be useful not only for systematic observation but also to measure and to encourage officers' skill.