摘 要

目前，现代科学技术与社会经济发展到了一定的高度，互联网的应用已经深入到大众的生产生活中。物流产业作为我国现代经济的重要驱动力量，也处于一个飞速发展的时期。交通运输在物流业中属于主控因素，互联网与物流运输的结合产生了智能物流运输，智能物流运输的产生大大提高了物流行业的工作效率，智能物流运输车队的普及能够更加合理的调配运输资源，大幅度的提高了物流的运输效率，从而降低社会总成本。

然而，车辆在运输的过程中经常会遇到交通拥堵的情况，极易发生交通事故。提高运输环境质量和道路交通安全质量，减少拥堵情况，成为交通运输亟待解决的重要问题。为此人们研发出车载自组织网络（Vehicular Ad Hoc Network VANET），移动VANET网络是一种应用于交通运输领域的、移动的、无线无中心的、跳跃的自组织网络。它将运输车队中的每个车辆作为节点，每个节点在移动VANET网络中进行数据通信。由于节点的高速频繁地移动，移VANET动网络自身具有拓扑结构和周围复杂的运输环境，在节点之间进行信息传输尤其是安全信息的广播和通讯的时候，会出现隐藏终端问题，导致数据包丢失，降低运输车辆行驶的安全性。

本论文在介绍在智能物流运输这个背景之下详细的切入移动VANET网络和隐藏终端问题，主要探讨在智能物流运输车队中抑制隐藏终端的方法，是基于一种位图的检测分析法来对隐藏终端问题进行解决。通过实践证明，以位图为原理的方法能够有效地解决在智能物流运输车队中由隐藏终端造成的数据包丢包问题，大大地降低了丢包率，保障物流车队的安全运输。从论文的开题到结束，主要的工作包括一下几个内容：

（1）本论文前期对智能物流尤其是智能物流运输做了详细的了解，并根据其国内外的研究现状，具体阐释了智能物流及智能物流运输的定义，典型特点以及发展趋势，能够更直观的看出本文的研究背景。

（2）中期本文主要车载自组织网络以及相关理论的知识收集，在论文中对其进行归纳和整理，具体在论文中体现为对移动VANET网络的相关概念进行具体的阐述，分析其优劣性后引出隐藏终端问题，并总结了常见的几种解决隐藏终端的方法。

（3）本文在中后期根据自己对车载网络以及隐藏终端的了解，提出了一种基于位图的新的方法来处理隐藏终端，从构建特殊的网络模型，到提出一种新的算法，比较全面的说明该方法能够抑制隐藏终端问题。

最后本文利用Visual Basic开发车载自组织网络中数据冲突检测软件，通过确定协议以及网络中的车辆，用来对车辆节点进行模拟场景，通过场景状况来说明位图能够有效的抑制隐藏终端问题。

关键词：智能物流；智能物流运输；车载自组织网络；隐藏终端；位图分析法

Research on the Method of Suppressing Hidden Terminal in Intelligent Logistics Transportation Fleet

ABSTRACT

At present, modern science and technology and social and economic development have reached a certain height, and the application of the Internet has penetrated into the production and life of the masses. As an important driving force of China's modern economy, the logistics industry is also in a period of rapid development. Transportation is the main controlling factor in the logistics industry. The combination of the Internet and logistics and transportation has produced intelligent logistics transportation. The generation of intelligent logistics transportation has greatly improved the efficiency of the logistics industry. The popularity of the intelligent logistics transportation fleet can more rationally allocate transportation resources. , greatly improving the transportation efficiency of logistics, thereby reducing the total cost of society.

However, vehicles often encounter traffic jams during transportation and are prone to traffic accidents. Improving the quality of the transportation environment and the safety and quality of road traffic and reducing congestion have become important issues for transportation. To this end, people have developed a Vehicular Ad Hoc Network (VANET), a mobile, wireless, non-central, jumping self-organizing network used in the transportation field. It will transport each vehicle in the fleet as a node, with each node communicating data in a mobile VANET network. Due to the high-speed frequent movement of nodes, the mobile VANET mobile network itself has a topological structure and a complex transportation environment around it. When information is transmitted between nodes, especially broadcast and communication of security information, hidden terminal problems may occur, resulting in data packets. Lost and reduce the safety of transport vehicles.

This paper introduces the detailed mobile VANET network and hidden terminal problem under the background of intelligent logistics transportation. It mainly discusses the method of suppressing hidden terminals in intelligent logistics transportation fleet. It is based on a bitmap monitoring analysis method to hide the terminal problem is solved. It has been proved by practice that the bitmap-based method can effectively solve the packet loss problem caused by hidden terminals in the intelligent logistics transportation fleet, greatly reducing the packet loss rate and ensuring the safe transportation of the logistics fleet. From the opening of the paper to the end, the main work includes several things:

(1) In the early stage of this thesis, a detailed understanding of intelligent logistics, especially intelligent logistics transportation, was made. According to the research status at home and abroad, the definition of intelligent logistics and intelligent logistics transportation, typical characteristics and development trends, can be seen more intuitively. The research background of this paper.

(2) In the medium term, this paper mainly collects and organizes the knowledge of the vehicle self-organizing network and related theories, and summarizes and organizes them in the paper. In the paper, it is embodied in the paper to explain the related concepts of the mobile VANET network, and analyze its advantages and disadvantages. Hidden terminal problems, and summarized several common ways to solve hidden terminals.

(3) In the middle and later period, based on his understanding of the in-vehicle network and hidden terminals, this paper proposes a new bitmap-based method to deal with hidden terminals, from constructing a special network model to proposing a new algorithm. The algorithm can detect whether the hidden terminal exists and solve the problem through random gap.