【摘要】：水下傳感器網(wǎng)絡(luò)研究已變得越來(lái)越重要,其擁有廣泛的應(yīng)用領(lǐng)域,如海軍戰(zhàn)術(shù)監(jiān)視、海洋數(shù)據(jù)采集、近�？碧揭约盀�(zāi)難預(yù)防等。由于在海水中無(wú)線(xiàn)電和光波嚴(yán)重衰減,聲通信技術(shù)是水下傳感網(wǎng)采用的典型物理層通信技術(shù),也就是水聲傳感網(wǎng)絡(luò)(UASNs)。然而,水下聲波速度僅約為1500 m/s,比無(wú)線(xiàn)電傳播速度低五個(gè)數(shù)量級(jí)。而水中聲信道帶寬僅為無(wú)線(xiàn)電信道的千分之一。因此,相比無(wú)線(xiàn)傳感網(wǎng)(WSNs),UASNs具有傳播延遲長(zhǎng)和可用帶寬有限等特點(diǎn),這對(duì)網(wǎng)絡(luò)協(xié)議棧和應(yīng)用設(shè)計(jì)提出極大挑戰(zhàn)。與WSNs相似,媒體訪(fǎng)問(wèn)控制(MAC)協(xié)議在UASNs中扮演了重要的角色,直接影響著網(wǎng)絡(luò)整體性能。當(dāng)前,對(duì)于UASNs中MAC協(xié)議的理論分析研究多關(guān)注于單跳拓?fù)�。然�?多跳網(wǎng)絡(luò)實(shí)用性更高,并能提供更大的覆蓋范圍。因此,本文將研究多跳拓?fù)渖闲诺涝L(fǎng)問(wèn)協(xié)議的性能。本文的具體內(nèi)容研究如下:首先,本文針對(duì)一個(gè)已有的Aloha協(xié)議性能分析模型進(jìn)行研究,該模型隱含地假設(shè)一個(gè)節(jié)點(diǎn)可以同時(shí)發(fā)出兩個(gè)數(shù)據(jù)包,而這與水聲信道的半雙工特性不符。基于這個(gè)發(fā)現(xiàn),本文提出了一個(gè)改進(jìn)的分析模型并通過(guò)NS-3構(gòu)造仿真實(shí)驗(yàn)對(duì)其進(jìn)行驗(yàn)證。仿真顯示,改進(jìn)的分析模型比原模型更精確。其次,本文提出了一個(gè)Slotted Aloha協(xié)議性能分析模型,并證明其傳輸服從獨(dú)立的伯努利過(guò)程。通過(guò)分析網(wǎng)絡(luò)利用率的上界,本文進(jìn)一步獲得了針對(duì)特定負(fù)載最大發(fā)揮網(wǎng)絡(luò)性能的最佳節(jié)點(diǎn)數(shù)。分析與仿真數(shù)據(jù)表明,該模型具有很高的精確性。通過(guò)分析發(fā)現(xiàn),Aloha協(xié)議和Slotted Aloha協(xié)議更適用于負(fù)載較輕的網(wǎng)絡(luò)。
[Abstract]:The research of underwater sensor networks has become more and more important, and it has a wide range of applications, such as naval tactical surveillance, marine data acquisition, offshore exploration and disaster prevention. Due to the serious attenuation of radio and light waves in seawater, acoustic communication technology is a typical physical layer communication technology used in underwater sensor networks, that is, underwater acoustic sensor network (UASNs). However, the underwater acoustic velocity is only about 1500 m / s, which is five orders of magnitude lower than the radio propagation speed. The bandwidth of underwater acoustic channel is only 1/1000 of that of wireless channel. Therefore, compared with the wireless sensor network (WSNs), UASNs, it has the characteristics of long propagation delay and limited available bandwidth, which poses a great challenge to the network protocol stack and application design. Similar to WSNs, media access control (MAC) protocol plays an important role in UASNs, which directly affects the overall performance of the network. At present, the theoretical analysis of MAC protocol in UASNs focuses on single hop topology. However, multi-hop network is more practical and can provide greater coverage. Therefore, this paper will study the performance of channel access protocols on multi-hop topology. The specific contents of this paper are as follows: firstly, this paper studies an existing Aloha protocol performance analysis model, which implicitly assumes that one node can send two packets at the same time. This is not consistent with the half-duplex characteristics of underwater acoustic channel. Based on this discovery, an improved analysis model is proposed and verified by NS-3 construction simulation experiment. The simulation results show that the improved analysis model is more accurate than the original model. Secondly, this paper proposes a performance analysis model of Slotted Aloha protocol, and proves that its transmission obeys the independent Bernoulli process. By analyzing the upper bound of network utilization, the optimal number of nodes to maximize network performance for specific loads is obtained in this paper. The analysis and simulation data show that the model has high accuracy. Through the analysis, it is found that Aloha protocol and Slotted Aloha protocol are more suitable for networks with light load.
【學(xué)位授予單位】：哈爾濱工程大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2014
【分類(lèi)號(hào)】：TP212.9;TN929.3

【參考文獻(xiàn)】

相關(guān)期刊論文 前1條

1 周密;崔勇;徐興福;楊旭寧;;水聲傳感網(wǎng)MAC協(xié)議綜述[J];計(jì)算機(jī)科學(xué);2011年09期

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本文編號(hào)：2473724