本文選題：移動(dòng)自組織網(wǎng)絡(luò) + 傳輸策略　； 參考：《電子科技大學(xué)》2014年碩士論文

【摘要】：在移動(dòng)自組織網(wǎng)絡(luò)中,根據(jù)某一路由準(zhǔn)則(比如跳數(shù)),源節(jié)點(diǎn)或中繼節(jié)點(diǎn)通往目的節(jié)點(diǎn)的下一跳節(jié)點(diǎn)往往不只有一個(gè)可以選擇,缺省采取的方法是隨機(jī)選擇下一跳節(jié)點(diǎn),但這種選擇方式會(huì)引起一些節(jié)點(diǎn)的擁塞增大端到端時(shí)延并且浪費(fèi)網(wǎng)絡(luò)資源。本文提出了基于Q學(xué)習(xí)算法的MANETs網(wǎng)絡(luò)分組傳輸策略來合理選擇通往目的節(jié)點(diǎn)下一跳節(jié)點(diǎn),Q學(xué)習(xí)算法通過執(zhí)行動(dòng)作并且獲得執(zhí)行動(dòng)作以后獲得的獎(jiǎng)賞值來更新相應(yīng)動(dòng)作的Q值,并基于Q值和一定的動(dòng)作選擇策略來決定下一跳節(jié)點(diǎn)。本文在OPNET環(huán)境下進(jìn)行算法實(shí)現(xiàn)以及性能仿真,同隨機(jī)選擇下一跳節(jié)點(diǎn)的傳輸策略做端到端時(shí)延性能上的對比,通過對比可以發(fā)現(xiàn)基于Q學(xué)習(xí)算法的MANETs網(wǎng)絡(luò)并發(fā)分組傳輸策略的端到端時(shí)延要明顯低于隨機(jī)選擇下一跳節(jié)點(diǎn)傳輸策略的端到端時(shí)延。本文首先采用了基于當(dāng)前Q值的貪心動(dòng)作選擇策略,在進(jìn)行性能分析時(shí)發(fā)現(xiàn)其存在的問題:在單次的動(dòng)作選擇中只參考當(dāng)前的Q值而并不考慮以往的經(jīng)驗(yàn),可能做出錯(cuò)誤決定。因此本文又提出了基于Q值平均值的貪心動(dòng)作選擇策略,這樣在執(zhí)行動(dòng)作選擇時(shí)就可以從全局角度對比可選動(dòng)作的優(yōu)劣。同時(shí)基于Q平均值的貪心動(dòng)作選擇策略在時(shí)延性能上要比基于當(dāng)前Q值的貪心動(dòng)作選擇策略的Q學(xué)習(xí)算法更加穩(wěn)定。另外一方面,在存在干擾的場景下如何高效、正確地進(jìn)行數(shù)據(jù)傳輸也是一個(gè)需要解決的問題。本文引入了近年來的研究熱點(diǎn)—網(wǎng)絡(luò)編碼的思想提出了基于隨機(jī)線性網(wǎng)絡(luò)編碼的端到端傳輸策略,并在OPNET環(huán)境下協(xié)同MATLAB加以實(shí)現(xiàn),同停等ARQ協(xié)議做了仿真性能的對比,通過對比發(fā)現(xiàn)基于隨機(jī)線性網(wǎng)絡(luò)編碼的端到端傳輸策略在傳輸有效性上要優(yōu)于停等ARQ協(xié)議。最后本文對編碼塊的大小對傳輸性能的影響做了研究,發(fā)現(xiàn)編碼塊較大數(shù)據(jù)傳輸?shù)膶?shí)時(shí)性差,但是有效比特率高,編碼塊較小數(shù)據(jù)傳輸?shù)膶?shí)時(shí)性好,但是有效比特率低。
[Abstract]:In a mobile ad hoc network, the next hop node from the source node or relay node to the destination node often has more than one choice according to the criteria (such as hops), and the default method is to select the next hop node randomly. However, this method can cause congestion of some nodes to increase end-to-end delay and waste network resources. In this paper, a MANETs network packet transmission strategy based on Q learning algorithm is proposed to reasonably select the Q value of the next hop node to the destination node by performing the action and obtaining the reward value obtained after the action is performed to update the Q value of the corresponding action. And based on Q value and certain action selection strategy to determine the next hop node. In this paper, the algorithm implementation and performance simulation are carried out in OPNET environment, which is compared with the end-to-end delay performance of random next hop node transmission strategy. It is found that the end-to-end delay of the concurrent packet transmission strategy in MANETs networks based on Q learning algorithm is significantly lower than that of the next hop node transmission strategy selected at random. In this paper, the greedy action selection strategy based on the current Q value is first adopted, and the problem is found in the performance analysis: in a single action selection, only the current Q value is referred to and the previous experience is not taken into account, and the wrong decision may be made. Therefore, a greedy action selection strategy based on the average Q value is proposed in this paper, so as to compare the advantages and disadvantages of the optional action from a global perspective when performing the action selection. At the same time, the greedy action selection strategy based on Q average is more stable than the Q learning algorithm based on the current Q value based greedy action selection strategy. On the other hand, how to transmit data efficiently and correctly in the presence of interference is also a problem to be solved. In this paper, an end-to-end transmission strategy based on stochastic linear network coding is proposed by introducing the idea of network coding, which is a hot research topic in recent years. The scheme is implemented by cooperative MATLAB in OPNET environment. The simulation performance of ARQ protocol is compared with that of ARQ protocol such as stop. It is found that the end-to-end transmission strategy based on stochastic linear network coding is superior to the stopping ARQ protocol in terms of transmission efficiency. Finally, the effect of the size of the coding block on the transmission performance is studied. It is found that the real time performance of the larger data transmission block is poor, but the effective bit rate is high, and the real time performance of the coding block smaller data transmission is good, but the effective bit rate is low.
【學(xué)位授予單位】：電子科技大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2014
【分類號】：TN929.5

【參考文獻(xiàn)】

相關(guān)碩士學(xué)位論文 前1條

1 嚴(yán)雯;Linux系統(tǒng)下OLSR路由協(xié)議研究及實(shí)現(xiàn)[D];電子科技大學(xué);2009年

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本文編號：1837392