• Title/Summary/Keyword: VDES

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Optimization of Resource Allocation for Inter-Channel Load Balancing with Frequency Reuse in ASO-TDMA-Based VHF-Band Multi-Hop Data Communication System (ASO-TDMA기반 다중-홉 VHF 대역 데이터 통신 시스템의 주파수 재사용을 고려한 채널간 부하 균형을 위한 자원 할당 최적화)

  • Cho, Kumin;Lee, Junman;Yun, Changho;Lim, Yong-Kon;Kang, Chung G.
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.40 no.7
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    • pp.1457-1467
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    • 2015
  • Depending on the type of Tx-Rx pairs, VHF Data Exchange System (VDES) for maritime communication is expected to employ the different frequency channels. Load imbalance between the different channels turns out to be a critical problem for the multi-hop communication using Ad-hoc Self-Organizing TDMA (ASO-TDMA) MAC protocol, which has been proposed to provide the connectivity between land station and remote ship stations. In order to handle the inter-channel load imbalance problem, we consider a model of the stochastic geomety in this paper. After analyzing the spatial reuse efficiency in each hop region by the given model, we show that the resource utility can be maximized by balancing the inter-channel traffic load with optimal resource allocation in each hop region.

Performance Analysis of Multiple Access Protocol for Maritime VHF Data Exchange System (VDES) (해상 초단파 대역 데이터 교환 시스템을 위한 다중 접속 방식의 성능 분석 연구)

  • Yun, Changho;Cho, A-Ra;Kim, Seung-Geun;Lim, Yong-Kon
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.18 no.12
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    • pp.2839-2846
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    • 2014
  • New VHF band for use in VDE is determined by WRC-12 due to the overload of AIS VDL, and the system characteristics of the VDE is recommended as ITU-R M. 1842-1. CS-TDMA, a multiple access method of AIS class B, is recommended as that of the VDE. It is inefficient for CS-TDMA just applying the report interval used in AIS class B to transmit high speed data with higher payload in the aspect of efficiency. In this paper, a simulation is executed in order to determine adequate report interval according to the number of active ships that affects directly network traffic. To this end, the performance of CS-TDMA, which includes the number of received packets, reception success rate, channel utilization, and collision rate, is investigated via a simulation.

Design and experiment of the protocol using ASM2.0 : focusing on marine officers' mandatory reporting items (차세대 해상디지털통신기술 ASM2.0을 이용한 프로토콜 설계 및 실험 : 항해사의 의무보고 사항을 중심으로)

  • Kim, Kilyong;Kim, Do-yeon;Lee, Seojeong
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2015.10a
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    • pp.43-44
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    • 2015
  • AIS-ASM is a one of the study to provide a variety of maritime safety information as well as ship's position and navigational information that is their own function since 2004. This study aims to reduce the marine officer's workload through automating marine officer's mandatory reporting items using the one of the next maritime digital communication technology (ASM2.0). For this purpose, we designed and experimented of the ASM2.0 protocol through analyzing a domestic regulation about passenger flight and AIS-ASM message.

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Design and realization of the passenger ship's MSP service system using ASM2.0 : focusing on captain's mandatory reporting items (차세대 해상디지털통신기술 ASM2.0을 이용한 여객선 MSP서비스 시스템 설계 및 구현)

  • Kim, Kilyong;Kim, Do-yeon;Lee, Seojeong
    • Journal of Digital Contents Society
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    • v.16 no.6
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    • pp.871-882
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    • 2015
  • AIS-ASM is one of the studies to provide a variety of maritime safety information as well as the information on a ship's position that is their own function, and AIS-ASM has been implemented with adjustment of the relevant regulations since 2004. However, it was reported that the increased use of ASM message on the existing AIS channel affects the part of the existing AIS own function such as the transmission of the ship's position and safe-related information. Also, seamless MSP service is difficult to provide at a low transmission rate of the existing AIS channel. This study aims to reduce the marine officer's workload through automating captain's mandatory reporting items using the one of the next maritime digital communication technology (ASM2.0). For this purpose, we designed and realized the ASM2.0 protocol through analyzing domestic regulations about passenger flight and AIS-ASM message.