【正文】 ............................ 42 論文總結(jié) ....................................................................................................................... 42 下一步工作 ................................................................................................................... 42 致謝 ............................................................................................................................................. 44 參考文獻(xiàn) ..................................................................................................................................... 45 常州工學(xué)院延陵學(xué)院 1 第一章 前言 研究背景與 意義 車輛自組織網(wǎng)絡(luò)（ Vehicular Ad Hoc Networks， VANET） [1]作為一種特殊的移動(dòng)自組織網(wǎng)絡(luò)，是道路上車輛間、車輛與固定接入點(diǎn)之間相互通信而組成的開放式移動(dòng)網(wǎng)絡(luò)。 關(guān)鍵詞 ： 移動(dòng)自組網(wǎng)，車載網(wǎng)， NS2，無(wú)狀態(tài)貪心算法 ABSTRACT Vehicle ad hoc work routing protocol analysis and simulation ABSTRACT In recent years, our life is more better than before, and the design for life quality is more and more popular. One of the examples are that vehicular cars bee very mon in our life. More and more cars are on the road and thus cause big problems to traffic. How to reduce the traffic and accident happen are in hot research. The good design traffic are that cars could municate with frequency and the traffic accident is small. And the driver could get enough information to deal with the ining bad condition. With the propose the research is more and more serious if we not deal with the problems. Vehicular Ad Hoc Network contains many important technologies. such as how to access the medium which used in Vehicular Ad Hoc Network, Global Positioning System and the routing protocol which are used in Vehicular Ad Hoc Network. AODV is widely used in Ad hoc mobile work, which is a widely used routing protocol, GPSR is another routing protocol which are used in Vehicular Ad Hoc Network。二種協(xié)議傳送相同的數(shù)據(jù)包，由于 GPSR 協(xié)議延時(shí)小，故吞吐量較大，抖動(dòng)比較小。改進(jìn)后的算法在接收包的成功率、發(fā)送包的延時(shí)、抖動(dòng)率、吞吐量要優(yōu)于 GPSR 協(xié)議。模擬了車載網(wǎng)節(jié)點(diǎn)的移動(dòng)。 在本文中，主要介紹了 NS2 的仿真平臺(tái)及其體系框架結(jié)構(gòu)。其中重點(diǎn)分析了 AOD與 GPSR 這二種協(xié)議的原理。 車載網(wǎng)分類可以分成：基于拓?fù)涞穆酚蓞f(xié)議，基于地理的路由協(xié)議，基于地圖的路由協(xié)議。在我看來，如果能夠?qū)崿F(xiàn)車輛間的通信，使得車輛之間能夠迅速、快捷的獲得其他車輛的信息，從而讓駕駛者能快速的做出正確的反應(yīng)，那么就可以很大限度的降低交通事故的 發(fā)生，從而能在一定的程度上緩解道路的擁堵。這些問題都給現(xiàn)代的交通系統(tǒng)提出嚴(yán)峻的挑戰(zhàn)。摘要 隨著科學(xué)技術(shù)的不斷發(fā)展與進(jìn)步，人們的生活水平在逐漸的提高，對(duì)生活質(zhì)量也有了越來越高的要求，越來越多的家庭開始擁有私家車了。然后更多的汽車出現(xiàn)在了道路上，造成了道路上的嚴(yán)重?fù)矶?，從而交通事故也有了逐漸增長(zhǎng)的趨勢(shì)?，F(xiàn)在交通系統(tǒng)需要解決的問題是怎樣減少交通事故的發(fā)生，堅(jiān)決這個(gè)問題的關(guān)鍵是怎樣提高道路交通環(huán)境的質(zhì)量。車載網(wǎng)的關(guān)鍵技術(shù)包括：車載自組網(wǎng)無(wú)線接入技術(shù)、 GPS 定位技術(shù)、自組網(wǎng)路由協(xié)議。本文選用 AODV 路由協(xié)議與 GPSR 協(xié)議進(jìn)行對(duì)比分析。在網(wǎng)絡(luò)迅速膨脹的今天，隨著網(wǎng)絡(luò)規(guī)模的不斷增大，網(wǎng)絡(luò)因素類型不斷增多時(shí)，傳統(tǒng)的以經(jīng)驗(yàn)為主的網(wǎng)絡(luò)設(shè)計(jì)方法已經(jīng)不能夠適應(yīng)現(xiàn)在的需求，且用現(xiàn)實(shí)中真實(shí)存在的通信元素進(jìn)行測(cè)試，會(huì)造成資源和時(shí)間的浪費(fèi)，因此，利用網(wǎng)絡(luò)仿真工具 在模擬的環(huán)境中對(duì)其網(wǎng)絡(luò)性能進(jìn)行仿真顯得非常重要。其中包括仿真工具 NS2。在測(cè)試場(chǎng)景中，對(duì)比了二種不同的協(xié)議下吞吐量、抖動(dòng)率、延時(shí)、丟包率的比較。最后，得到的結(jié)論為：由于 GPSR 算法通過貪心算法，選取的是最遠(yuǎn)的節(jié)點(diǎn)作為轉(zhuǎn)發(fā)中繼，故延時(shí)相對(duì)于 AODV 算法比較而言，端到端延時(shí)更小。仿 真也表明，使用 GPSR 算法，丟包率也較低。 We chose the NS2 simulation to analysis which routing protocol is much better suitable for the mobile vehicle ad hoc work. We test a simulation, 20 percent of mobile nodes are moved with the speed of fifteen, twenty, twentyfive km/s, and so on. And then we pare some very important parameters. Such as delay time, throughout, jitter and loss packet ratio. Finally, we can get the conclusion that GPSR routing protocol is more suitable for Vehicular Ad Hoc Network .With the reason of GPSR chose the fastest nodes to act as forward nodes, which will cause small average time. At the traffic almost the same, so the throughout is much more bigger than the way of using the routing protocol using AODV. Keywords： Ad hoc work, Vehicular Ad Hoc Network, NS – 2, GPSR 目錄 I 目錄 第一章 前言 ................................................................................................................................. 1 研究背景與意義 ............................................................................................................. 1 國(guó)內(nèi)外研究現(xiàn)狀 ............................................................................................................. 2 主要研究工作 ................................................................................................................. 2 論文結(jié)構(gòu) ......................................................................................................................... 3 第二章 車載自組 網(wǎng)現(xiàn)狀 ............................................................................................................. 4 車載自組網(wǎng)概述 .............................................................................................................. 4 車載自組網(wǎng)的特點(diǎn) ............................................................................................... 4 車載自組網(wǎng)的體系結(jié)構(gòu) ....................................................................................... 6 車 載自組網(wǎng)中的關(guān)鍵技術(shù) ............................................................................................. 7 車載自組網(wǎng)無(wú)線接入技術(shù) .................................................................................... 7 GPS 定位技術(shù) ........................................................................................................ 7 車載自組網(wǎng)路由協(xié)議 ........................................................................................... 8 2． 3 車載自組網(wǎng)路由協(xié)議的分類 ...................................................................................... 8 基于拓?fù)涞穆酚蓞f(xié)議 ........................................................................................... 9 基于地理位置路由協(xié)議 ..................................................................................... 10 基于地圖的路由協(xié)議 ......................................................................................... 12 本章小結(jié) ....................................................................................................................... 12 第三章 NS2 模擬與仿真工具 ................................................................................................... 14 車載網(wǎng)算法的 NS2 仿真平臺(tái)構(gòu)建 ............................................................................... 14 網(wǎng)絡(luò)仿真的方法和一般過程 .......