【作者】 咸魁蔚；

【导师】 刘敬浩；

【作者基本信息】 天津大学 ， 通信与信息系统， 2010， 硕士

【摘要】 近些年来,随着航海技术和运输业务的不断发展,船舶速度及船舶数量不断提高,从而使得海上交通密度越来越大,给船舶避碰、港口交管和航行安全提出了新的要求。在这种情况下,雷达和VHF无线电话越来越不能适应航海安全的要求,自动识别系统(AIS)应运而生了。AIS的发送台站利用同步获得了时隙信息,通过初始化阶段的监听信道而得到了信道时隙的使用状况,然后按照四种传输协议规定的算法选择消息的传输时隙并且按照规定的格式封装消息后传输。接收台站接收到消息后按照既定格式解封,并且标识相应的时隙状态,为以后本台站传输时隙的选择做了准备。本文经过对AIS中传输协议的研究,使用C++编程语言,实现了AIS设备的传输协议。并且按照上述的运行过程,完成了AIS的主要功能。本论文的主要工作和结果如下:1、本文使用C语言实现了AIS的RATDMA、SOTDMA和ITDMA协议,以及消息的封装和解封,便于以后向硬件平台上移植。2、本文使用多线程编程技术和网络通信技术,将客户端作为船载AIS设备,利用计时线程实现了时隙同步,通过服务器使得彼此之间能够相互传送消息。3、本文实现了AIS的初始化、网络登录、第一帧、连续运行和改变报告率的连续运行。更多还原

【Abstract】 In recent years, with the development of marine technology and business transportation, the number and speed of vessels continually improved, so that the increase in maritime traffic density put forwards new demands for collision avoidance, traffic control and navigation and port safety .In this situation, radar and VHF radiotelephone cannot meet the marine safety requirements, so AIS comes into being.By time synchronization, AIS stations obtain slot information .When in the initialization stage AIS stations obtain slot status by monitoring the channel, and then AIS stations select Nominal Transmission Slot in the light of four kinds of information transmission protocols and transfer messages after packaging. When receiving messages receiving stations should decoding data in accordance with corresponding format, and identify slot’s status for the future choice of stations’transmission slot.Based on the study of AIS transmission protocols, by using VC++, the design realize transmission protocols and AIS main functions according above. The achievement of the design is showed as flows:1. The design realizes AIS protocols of RATDMA, SOTDMA and ITDMA and information packaging by using C language, easier for transplanting to the hardware platform.2. The design using client program as shipboard AIS device ,by using multi-threading technology and network communication technology and the timing thread achieving slot synchronization ,achieves messages’transport to each other.3. The paper achieves AIS continuous operation of stages of initialization, network logon, first frame, continuous operation and change the reporting rate.更多还原