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1、<p><b>  淮 陰 工 學(xué) 院</b></p><p>  畢業(yè)設(shè)計(jì)(論文)外文資料翻譯</p><p>  注:請(qǐng)將該封面與附件裝訂成冊(cè)。附件1:外文資料翻譯譯文</p><p>  無(wú)線傳感器網(wǎng)絡(luò)的實(shí)現(xiàn)及在農(nóng)業(yè)上的應(yīng)用</p><p><b>  1引言</b></p&g

2、t;<p>  無(wú)線傳感器網(wǎng)絡(luò)(Wireless Sensor Network ,WSN)就是由部署在監(jiān)測(cè)區(qū)域內(nèi)大量的廉價(jià)微型傳感器節(jié)點(diǎn)組成,通過無(wú)線通信方式形成的一個(gè)多跳的自組織的網(wǎng)絡(luò)系統(tǒng)。其目的是協(xié)作地感知、采集和處理網(wǎng)絡(luò)覆蓋區(qū)域中感知對(duì)象的信息,并發(fā)送給觀察者?!皞鞲衅鳌⒏兄獙?duì)象和觀察者”構(gòu)成了網(wǎng)絡(luò)的三個(gè)要素。這里說的傳感器,并不是傳統(tǒng)意義上的單純的對(duì)物理信號(hào)進(jìn)行感知并轉(zhuǎn)化為數(shù)字信號(hào)的傳感器,它是將傳感器模塊、數(shù)據(jù)處

3、理模塊和無(wú)線通信模塊集成在一塊很小的物理單元,即傳感器節(jié)點(diǎn)上,功能比傳統(tǒng)的傳感器增強(qiáng)了許多,不僅能夠?qū)Νh(huán)境信息進(jìn)行感知,而且具有數(shù)據(jù)處理及無(wú)線通信的功能。借助傳感器節(jié)點(diǎn)中內(nèi)置的形式多樣的傳感器件,可以測(cè)量所在環(huán)境中的熱、紅外、聲納、雷達(dá)和地震波信號(hào)等信號(hào),從而探測(cè)包括溫度、濕度、噪聲、光強(qiáng)度、壓力、土壤成分、移動(dòng)物體的大小、速度和方向等等眾多我們感興趣的物質(zhì)現(xiàn)象。無(wú)線傳感器網(wǎng)絡(luò)是一種全新的信息獲取和信息處理模式。由于我國(guó)水資源已處于相當(dāng)

4、緊缺的程度,加上全國(guó)90%的廢、污水未經(jīng)處理或處理未達(dá)標(biāo)就直接排放的水污染,11%的河流水質(zhì)低于農(nóng)田供水標(biāo)準(zhǔn)。水是農(nóng)業(yè)的命脈,是生態(tài)環(huán)境的控制性要素,</p><p>  2無(wú)線傳感器網(wǎng)絡(luò)概述</p><p>  2.1無(wú)線傳感器網(wǎng)絡(luò)的系統(tǒng)架構(gòu)</p><p>  無(wú)線傳感器網(wǎng)絡(luò)的系統(tǒng)架構(gòu)如圖1所示,通常包括傳感器節(jié)點(diǎn)、匯聚節(jié)點(diǎn)和管理節(jié)點(diǎn)。傳感器節(jié)點(diǎn)密布于觀測(cè)區(qū)域,

5、以自組織的方式構(gòu)成網(wǎng)絡(luò)。傳感器節(jié)點(diǎn)對(duì)所采集信息進(jìn)行處理后,以多跳中繼方式將信息傳輸?shù)絽R聚節(jié)點(diǎn)。然后經(jīng)由互聯(lián)網(wǎng)或移動(dòng)通信網(wǎng)絡(luò)等途徑到達(dá)管理節(jié)點(diǎn)。終端用戶可以通過管理節(jié)點(diǎn)對(duì)無(wú)線傳感器網(wǎng)絡(luò)進(jìn)行管理和配置、發(fā)布監(jiān)測(cè)任務(wù)或收集回傳數(shù)據(jù)。</p><p>  圖1無(wú)線傳感器網(wǎng)絡(luò)的系統(tǒng)架構(gòu)</p><p>  2.2無(wú)線傳感器網(wǎng)絡(luò)的特點(diǎn)</p><p> ?。?)自組織。由于網(wǎng)絡(luò)

6、所處物理環(huán)境及網(wǎng)絡(luò)本身的不可預(yù)測(cè)因素,如:不能預(yù)先精確設(shè)定節(jié)點(diǎn)的位置,也不能預(yù)先知道節(jié)點(diǎn)之間的相鄰關(guān)系,部分節(jié)點(diǎn)由于能量耗盡或其他原因而死亡,新的節(jié)點(diǎn)的加入等,使得網(wǎng)絡(luò)的布設(shè)和展開能夠無(wú)需依賴于任何預(yù)設(shè)的網(wǎng)絡(luò)設(shè)施,節(jié)點(diǎn)之間通過分層協(xié)議和分布式算法協(xié)調(diào)各自的行為,節(jié)點(diǎn)開機(jī)后就可以快速自動(dòng)地組成一個(gè)獨(dú)立的網(wǎng)絡(luò)多跳路由。</p><p>  (2)多跳路由。網(wǎng)絡(luò)中節(jié)點(diǎn)通信距離有限,節(jié)點(diǎn)只能與它的鄰居直接通信,如果與其射

7、頻覆蓋范圍之外的節(jié)點(diǎn)進(jìn)行通信,則需要通過中間節(jié)點(diǎn)進(jìn)行路由。</p><p>  (3)大面積的空間分布,節(jié)點(diǎn)密集,數(shù)量巨大。</p><p> ?。?)以數(shù)據(jù)為中心。在無(wú)線傳感器網(wǎng)絡(luò)中,人們通常只關(guān)心某個(gè)區(qū)域內(nèi)某個(gè)觀測(cè)指標(biāo)的數(shù)值,而不會(huì)去具體關(guān)心單個(gè)節(jié)點(diǎn)的觀測(cè)數(shù)據(jù)。</p><p> ?。?)節(jié)點(diǎn)能力受限。傳感器節(jié)點(diǎn)的能量、處理能力、存儲(chǔ)能力和通信能力等都十分有限。

8、</p><p> ?、匐娫茨芰渴芟蕖S捎趥鞲衅鞴?jié)點(diǎn)的微型化,節(jié)點(diǎn)的電池能量有限,而且由于物理限制難以給節(jié)點(diǎn)更換電池,所以傳感器節(jié)點(diǎn)的電池能量限制是整個(gè)無(wú)線傳感器網(wǎng)絡(luò)設(shè)計(jì)最關(guān)鍵的約束之一,它直接決定了網(wǎng)絡(luò)的工作壽命。</p><p>  ②計(jì)算和存儲(chǔ)能力有限。廉價(jià)微型的傳感器節(jié)點(diǎn)帶來了處理器能力弱、存儲(chǔ)器容量小的特點(diǎn),使得其不能進(jìn)行復(fù)雜的計(jì)算,而傳統(tǒng)Internet網(wǎng)絡(luò)上成熟的協(xié)議和算法相

9、對(duì)無(wú)線傳感器網(wǎng)絡(luò)而言開銷太大,難以使用,因此必須使用簡(jiǎn)單、有效的協(xié)議及算法,如ZigBee協(xié)議。</p><p> ?、弁ㄐ拍芰τ邢蕖Mǔ?,無(wú)線通信的能耗E與通信距離d的關(guān)系為:E=kdn。其中2<n<4。通常取n為3。</p><p>  2.3無(wú)線傳感器網(wǎng)絡(luò)存在的不足</p><p> ?。?)能量受限。傳感器節(jié)點(diǎn)通常由普通電池或鋰電池供電,能量有限

10、。在無(wú)人值守的環(huán)境中,也是無(wú)線傳感器網(wǎng)絡(luò)應(yīng)用的瓶頸之一。</p><p> ?。?)節(jié)點(diǎn)成本較高。目前市面上銷售的傳感器節(jié)點(diǎn)價(jià)格在千元以上,而無(wú)線傳感器網(wǎng)絡(luò)所需要的節(jié)點(diǎn)眾多,因此限制了無(wú)線傳感器網(wǎng)絡(luò)的推廣使用。</p><p> ?。?)安全性差。由于采用了無(wú)線信道、分布式控制等技術(shù),網(wǎng)絡(luò)更容易受到被動(dòng)竊聽、主動(dòng)入侵等攻擊。</p><p> ?。?)協(xié)作能力。單個(gè)

11、的傳感器節(jié)點(diǎn)往往不能完成對(duì)目標(biāo)的測(cè)量、跟蹤和識(shí)別,而需要多個(gè)傳感器節(jié)點(diǎn)通過算法交換信息,對(duì)所獲得的數(shù)據(jù)進(jìn)行加工、匯總和過濾,得到最終結(jié)果。</p><p>  3 無(wú)線傳感器網(wǎng)絡(luò)當(dāng)前在農(nóng)業(yè)中的應(yīng)用</p><p>  針對(duì)我國(guó)水資源緊缺以及農(nóng)田節(jié)水灌溉的需求,根據(jù)現(xiàn)有的農(nóng)田灌溉裝備條件,應(yīng)用領(lǐng)域作物、土壤、水源布點(diǎn)等情況,分析了目前實(shí)現(xiàn)精確農(nóng)業(yè)亟待解決的關(guān)鍵技術(shù)問題,提出一套采用無(wú)線傳感器

12、網(wǎng)絡(luò)技術(shù)、適合大面積農(nóng)田智能灌溉控制方法。</p><p>  3.1 系統(tǒng)工作原理</p><p>  研究單片機(jī)系統(tǒng)通過多個(gè)傳感器對(duì)濕度、溫度、降雨量、酸堿度、水分蒸發(fā)量(風(fēng)速)和空氣溫度等多種信息的采集來實(shí)現(xiàn)對(duì)農(nóng)田的精確自動(dòng)灌溉控制,輸出的信號(hào)信息通過無(wú)線全雙工數(shù)傳收發(fā)模塊傳送給控制中心(嵌入式系統(tǒng))來確定是否啟動(dòng)水泵為農(nóng)田供水,同時(shí)將此供水與否信息由GPRS通信通過Internet

13、傳送到遠(yuǎn)方控制中心實(shí)現(xiàn)遠(yuǎn)程監(jiān)控,并通過計(jì)算機(jī)中的一些模型來處理信息,做出供水計(jì)劃。</p><p>  3.2 無(wú)線傳感器網(wǎng)絡(luò)硬件設(shè)計(jì)</p><p>  無(wú)線傳感器網(wǎng)絡(luò)模型是不同于傳統(tǒng)無(wú)線網(wǎng)絡(luò)的基礎(chǔ)設(shè)施網(wǎng),通過在監(jiān)測(cè)區(qū)域內(nèi)隨意布撒大量傳感器節(jié)點(diǎn)(簡(jiǎn)稱節(jié)點(diǎn)),由各節(jié)點(diǎn)自行協(xié)調(diào)并迅速組建通信網(wǎng)絡(luò),在能量利用率優(yōu)先考慮原則下進(jìn)行工作任務(wù)劃分以獲取監(jiān)視區(qū)域信息。網(wǎng)絡(luò)的自組織特性體現(xiàn)在當(dāng)節(jié)點(diǎn)失效或

14、新節(jié)點(diǎn)加入時(shí)網(wǎng)絡(luò)能夠自適應(yīng)重新組建,以調(diào)整全局的探測(cè)精度,充分發(fā)揮資源優(yōu)勢(shì),即網(wǎng)絡(luò)中的各節(jié)點(diǎn)除具備數(shù)據(jù)采集功能外兼有數(shù)據(jù)轉(zhuǎn)發(fā)實(shí)現(xiàn)多跳的路由功能。無(wú)線傳感器網(wǎng)絡(luò)每類節(jié)點(diǎn)的組成一般都由數(shù)據(jù)采集、數(shù)據(jù)處理、數(shù)據(jù)傳輸和電源這四部分組成。其中每一個(gè)單片機(jī)系統(tǒng)的硬件設(shè)計(jì)和軟件設(shè)計(jì)都是一樣。本設(shè)計(jì)的研究設(shè)計(jì)方案是只針對(duì)一個(gè)單片機(jī)系統(tǒng)的。被監(jiān)測(cè)物理信號(hào)的形式?jīng)Q定了傳感器的類型。處理器通常選用嵌入式CPU,如MOTOROLA公司的68HC16、C51系列

15、單片機(jī)等。數(shù)據(jù)傳輸單元可以選擇由低功耗、短距離的無(wú)線通信模塊組成,但考慮防盜與自然損壞,本系統(tǒng)選擇功耗較大、傳輸距離較遠(yuǎn)的SA68D21DL,農(nóng)民可以在辦公室或家中安放主控制器。圖2描述了節(jié)點(diǎn)的組成,其中,箭頭的方向表示數(shù)據(jù)在節(jié)點(diǎn)中的流動(dòng)方向。</p><p>  圖2 傳感器網(wǎng)絡(luò)框圖</p><p><b>  3.3 主控系統(tǒng)</b></p><

16、;p>  在該系統(tǒng)中,控制主機(jī)作為連接Internet網(wǎng)和無(wú)線傳感器網(wǎng)絡(luò)之間的協(xié)議轉(zhuǎn)換網(wǎng)關(guān)。其硬件采用致遠(yuǎn)電子公司MiniARM嵌入式工控模塊。MiniISA系列采集板卡采用智能型板卡結(jié)構(gòu),即在板卡上內(nèi)置MCU。板載MCU對(duì)板卡上I/O端口進(jìn)行控制,實(shí)現(xiàn)I/O數(shù)據(jù)的緩存,從而降低板卡對(duì)于MiniISA接口主機(jī)的依賴,節(jié)省主機(jī)處理數(shù)據(jù)的時(shí)間,保證MiniISA系統(tǒng)更加高效的運(yùn)行。此外板載MCU可以對(duì)采集的數(shù)據(jù)或者輸出數(shù)據(jù)進(jìn)行進(jìn)一步的

17、處理。系統(tǒng)電路圖如圖3所示。</p><p>  圖3 主控系統(tǒng)結(jié)構(gòu)圖</p><p>  3.4遠(yuǎn)程控制系統(tǒng)主要設(shè)計(jì)</p><p>  GPRS通信系統(tǒng)、GPRS與Internet網(wǎng)絡(luò)接入系統(tǒng)、監(jiān)控中心主機(jī)友好界面顯示控制系統(tǒng)。這一部分硬件部分可以應(yīng)用現(xiàn)有的移動(dòng)公司與電信等互聯(lián)網(wǎng)資源,軟件考慮成本和專業(yè)功能可以自主開發(fā),建議應(yīng)用現(xiàn)有遠(yuǎn)程軟件,如《波爾遠(yuǎn)程控制》軟

18、件、湖南省遠(yuǎn)程監(jiān)控設(shè)備有限公司的RC-2000可視化遠(yuǎn)程控制軟件系統(tǒng)。</p><p><b>  結(jié) 語(yǔ)</b></p><p>  本文綜述了無(wú)線傳感器網(wǎng)絡(luò)的節(jié)點(diǎn)構(gòu)成、特點(diǎn),以及當(dāng)前在農(nóng)業(yè)領(lǐng)域的應(yīng)用,研究了基于嵌入式系統(tǒng)而設(shè)計(jì)出來的智能廣域農(nóng)田供水系統(tǒng),當(dāng)檢測(cè)到農(nóng)田缺水信息時(shí)能夠通過自動(dòng)控制繼電器來啟動(dòng)供水水泵,而且實(shí)現(xiàn)了遠(yuǎn)程GPRS通信,可以通過PC機(jī)來了解系統(tǒng)

19、的運(yùn)行狀況并可對(duì)其控制,能夠自動(dòng)采集土壤信息來自行確定是否啟動(dòng)水泵為農(nóng)田供水,這正符合我國(guó)農(nóng)村的基本國(guó)情。本系統(tǒng)操作簡(jiǎn)單,對(duì)系統(tǒng)改造一下,可以設(shè)計(jì)成庭院自動(dòng)供水系統(tǒng)、溫室自動(dòng)供水系統(tǒng)和花園自動(dòng)供水系統(tǒng)等,故本系統(tǒng)的可擴(kuò)展性比較好,前景比較廣闊。</p><p>  無(wú)線傳感器網(wǎng)絡(luò)作為當(dāng)今信息領(lǐng)域新的研究熱點(diǎn),涉及多學(xué)科交叉。隨著傳感器成本的降低以及相關(guān)問題解決方案的不斷優(yōu)化,如能耗更加小和數(shù)據(jù)融合算法、節(jié)點(diǎn)定位算

20、法的不斷完善,以及更加優(yōu)秀的無(wú)線射頻模塊,無(wú)線傳感器網(wǎng)絡(luò)將會(huì)在農(nóng)業(yè)領(lǐng)域有更廣泛的應(yīng)用。</p><p><b>  附件2:外文原文</b></p><p>  The realization of wireless sensor networks and applications in agriculture</p><p>  1 Intr

21、oduction</p><p>  Wireless sensor networks (Wireless Sensor Network, WSN) are deployed in the monitoring area by the large number of low-cost micro sensor nodes, wireless communication through the formation

22、of a multi-hop network self-organization. The aim is to perceive collaboration, collection and processing of network coverage in the perception of objects, and send observers. "Sensors, sensing object and the observ

23、er," constitute the three elements of the network. Here that the sensor is not in the traditiona</p><p>  2 Overview of wireless sensor networks</p><p>  2.1 The system architecture of wire

24、less sensor networks</p><p>  Wireless sensor network system architecture shown in Figure 1, typically include sensor nodes, aggregation nodes and management nodes. Clouds in the observation area sensor node

25、s in order to constitute a network of self-organized manner. Sensor node processing the collected information, the way to multi-hop relay the information transmitted to the sink node. Then through the Internet or mobile

26、communication network and other channels to reach management node. End-users through the management of </p><p>  2.2 The characteristics of wireless sensor networks</p><p>  (1) self-organizatio

27、n. As the network and the network itself, the physical environment in which the unpredictability of factors, such as: can not pre-set exact location of the node can not know in advance the relationship between the nodes

28、adjacent to some nodes because of energy depletion or other causes of death, newnodes join and so on, make the network deployment and expansion without the need to rely on any of the default network infrastructure, layer

29、ed protocol between nodes and distribute</p><p>  (2) multi-hop routing.Limited communication distance of nodes in the network, the node can only communicate directly with its neighbors, if beyond the range

30、of its RF communication nodes, you need to be routed through intermediate nodes.</p><p>  (3) the spatial distribution of a large area, node density, the number is huge.</p><p>  (4) data-center

31、.In wireless sensor networks, people usually only care about a region within a certain numerical observations, and not to the specific observations concerned a single node.</p><p>  (5) node capacity constra

32、ints.The energy of sensor nodes, processing power, storage capacity and communication ability and so is very limited.</p><p> ?、?power energy restricted.As the miniaturization of sensor nodes, node battery p

33、ower is limited, and because physical constraints make it difficult for nodes to replace the battery, so battery power limitations of sensor nodes is the wireless sensor network design one of the most critical constraint

34、s, which directly determines the network's worklife.</p><p> ?、?computing and storage capacity is limited.Bring low-cost micro sensor nodes weak processor, memory capacity of small features, so it can no

35、t perform complex calculations, and the traditional Internet network protocols and algorithms on the relative maturity of wireless sensor networks, too costly, difficult to use,must therefore be simple, effective protoco

36、ls and algorithms, such as the ZigBee protocol.</p><p> ?、?communication is limited.Typically, the energy consumption of wireless communication and communication distance d E the relation: E = kdn.Where 2 &l

37、t;n <4.N is usually taken as 3.</p><p>  2.3 The shortcomings of wireless sensor networks</p><p>  (1) energy is limited. Sensor nodes are usually powered by ordinary batteries or lithium bat

38、teries, the energy limited.In unattended environments, wireless sensor network applications is one of the bottlenecks.</p><p>  (2) node cost is higher. Currently on the market price in thousands of sensor n

39、odes over the wireless sensor network nodes need many, limiting promote the use of wireless sensor networks.</p><p>  (3) The poor security. As a result of wireless channel, distributed control technology, t

40、he network more vulnerable to passive eavesdropping, active intrusion and other attacks.</p><p>  (4) collaboration. Individual sensor nodes are often unable to complete the target of measurement, tracking a

41、nd recognition, while the number of sensor nodes need to exchange information through the algorithm on data obtained for processing, aggregation and filtering, the final result.</p><p>  3 the current wirele

42、ss sensor network applications in agriculture</p><p>  View of the water shortage and the demand for farmland irrigation, irrigation equipment under the existing conditions of application fields of crops, so

43、il, water distribution, etc., for precise analysis of the current agricultural solved key technical problems, we propose a use ofwireless sensor network technology, suitable for large areas of agricultural land Intellige

44、nt Irrigation Control.3.1 The system works</p><p>  Of SCM system with multiple sensors on the humidity, temperature, rainfall, pH, water evaporation (wind speed) and air temperature, and other information

45、collection to achieve the precise automatic irrigation control field, the output of the signal information through a wireless full-dup lex Public data transmission sent to the control center transceiver module (embedded

46、systems) to determine whether to activate the pump for the farm water supply, water supply or not, this same information sent </p><p>  Wireless sensor network model is different from the traditional wireles

47、s network infrastructure, network, monitoring the region by a large number of sensor nodes randomly dispenser (the node), coordinated by the node and quickly set up their own communications network, under the principle o

48、f priority for energy efficiency division of work tasks for monitoring regional information .Self-organizing properties of the network when the node failure is reflected in the new node is added or when the ne</p>

49、<p>  In this system, the control network and Internet hosts as the connection between the wireless sensor network protocol conversion gateway. The hardware used Zhiyuan Electronics Mini ARM embedded computer modul

50、es. MiniISA series acquisition board structure using smart card, that card on the built-in MCU.MCU on the board on-board I / O ports control, to achieve I / O data buffer, thereby reducing the interface to the host board

51、 for Mini ISA dependence, saving the host data processing time, to ensur</p><p>  Concluding Remarks</p><p>  This paper reviews the nodes of wireless sensor networks, characteristics, and curre

52、nt applications in agriculture, research-based embedded systems, intelligent wide are a of farmland out of the water supply system, water is detected field information to continue through the automatic control Electric w

53、ater pump to start, and realized the remote GPRS communications, PC, to learn through the health system and over which it controlled, automatic acquisition of soil information to determine whether</p><p>  T

54、oday's wireless sensor network as a new hotspot in the field of information, involving interdisciplinary. With the reduced cost sensors and related solutions to continuous optimization problems, such as power consump

55、tion and data fusion algorithm is more small, node localization algorithm in continuous improvement, and more advanced wireless RF module, wireless sensor networks will be more in agriculture wide range of applications.&

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