外文翻譯---無線傳感器網絡的實現(xiàn)及在農業(yè)上的應用

1、<p><b>　　淮 陰 工 學 院</b></p><p>　　畢業(yè)設計(論文)外文資料翻譯</p><p>　　注：請將該封面與附件裝訂成冊。附件1：外文資料翻譯譯文</p><p>　　無線傳感器網絡的實現(xiàn)及在農業(yè)上的應用</p><p><b>　　1引言</b></p&g

2、t;<p>　　無線傳感器網絡（Wireless Sensor Network ,WSN）就是由部署在監(jiān)測區(qū)域內大量的廉價微型傳感器節(jié)點組成，通過無線通信方式形成的一個多跳的自組織的網絡系統(tǒng)。其目的是協(xié)作地感知、采集和處理網絡覆蓋區(qū)域中感知對象的信息，并發(fā)送給觀察者?！皞鞲衅?、感知對象和觀察者”構成了網絡的三個要素。這里說的傳感器，并不是傳統(tǒng)意義上的單純的對物理信號進行感知并轉化為數(shù)字信號的傳感器，它是將傳感器模塊、數(shù)據處

3、理模塊和無線通信模塊集成在一塊很小的物理單元，即傳感器節(jié)點上，功能比傳統(tǒng)的傳感器增強了許多，不僅能夠對環(huán)境信息進行感知，而且具有數(shù)據處理及無線通信的功能。借助傳感器節(jié)點中內置的形式多樣的傳感器件，可以測量所在環(huán)境中的熱、紅外、聲納、雷達和地震波信號等信號，從而探測包括溫度、濕度、噪聲、光強度、壓力、土壤成分、移動物體的大小、速度和方向等等眾多我們感興趣的物質現(xiàn)象。無線傳感器網絡是一種全新的信息獲取和信息處理模式。由于我國水資源已處于相當

4、緊缺的程度,加上全國90%的廢、污水未經處理或處理未達標就直接排放的水污染,11%的河流水質低于農田供水標準。水是農業(yè)的命脈,是生態(tài)環(huán)境的控制性要素,</p><p>　　2無線傳感器網絡概述</p><p>　　2.1無線傳感器網絡的系統(tǒng)架構</p><p>　　無線傳感器網絡的系統(tǒng)架構如圖1所示，通常包括傳感器節(jié)點、匯聚節(jié)點和管理節(jié)點。傳感器節(jié)點密布于觀測區(qū)域，

5、以自組織的方式構成網絡。傳感器節(jié)點對所采集信息進行處理后，以多跳中繼方式將信息傳輸?shù)絽R聚節(jié)點。然后經由互聯(lián)網或移動通信網絡等途徑到達管理節(jié)點。終端用戶可以通過管理節(jié)點對無線傳感器網絡進行管理和配置、發(fā)布監(jiān)測任務或收集回傳數(shù)據。</p><p>　　圖1無線傳感器網絡的系統(tǒng)架構</p><p>　　2.2無線傳感器網絡的特點</p><p>　　（1）自組織。由于網絡

6、所處物理環(huán)境及網絡本身的不可預測因素，如：不能預先精確設定節(jié)點的位置，也不能預先知道節(jié)點之間的相鄰關系，部分節(jié)點由于能量耗盡或其他原因而死亡，新的節(jié)點的加入等，使得網絡的布設和展開能夠無需依賴于任何預設的網絡設施，節(jié)點之間通過分層協(xié)議和分布式算法協(xié)調各自的行為，節(jié)點開機后就可以快速自動地組成一個獨立的網絡多跳路由。</p><p>　?。?）多跳路由。網絡中節(jié)點通信距離有限,節(jié)點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)點進行通信，則需要通過中間節(jié)點進行路由。</p><p>　?。?）大面積的空間分布，節(jié)點密集，數(shù)量巨大。</p><p>　?。?）以數(shù)據為中心。在無線傳感器網絡中，人們通常只關心某個區(qū)域內某個觀測指標的數(shù)值，而不會去具體關心單個節(jié)點的觀測數(shù)據。</p><p>　?。?）節(jié)點能力受限。傳感器節(jié)點的能量、處理能力、存儲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)點的微型化，節(jié)點的電池能量有限，而且由于物理限制難以給節(jié)點更換電池，所以傳感器節(jié)點的電池能量限制是整個無線傳感器網絡設計最關鍵的約束之一，它直接決定了網絡的工作壽命。</p><p>　?、谟嬎愫痛鎯δ芰τ邢?。廉價微型的傳感器節(jié)點帶來了處理器能力弱、存儲器容量小的特點，使得其不能進行復雜的計算，而傳統(tǒng)Internet網絡上成熟的協(xié)議和算法相

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

10、。在無人值守的環(huán)境中，也是無線傳感器網絡應用的瓶頸之一。</p><p>　?。?）節(jié)點成本較高。目前市面上銷售的傳感器節(jié)點價格在千元以上，而無線傳感器網絡所需要的節(jié)點眾多，因此限制了無線傳感器網絡的推廣使用。</p><p>　?。?）安全性差。由于采用了無線信道、分布式控制等技術，網絡更容易受到被動竊聽、主動入侵等攻擊。</p><p>　?。?）協(xié)作能力。單個

11、的傳感器節(jié)點往往不能完成對目標的測量、跟蹤和識別，而需要多個傳感器節(jié)點通過算法交換信息，對所獲得的數(shù)據進行加工、匯總和過濾，得到最終結果。</p><p>　　3 無線傳感器網絡當前在農業(yè)中的應用</p><p>　　針對我國水資源緊缺以及農田節(jié)水灌溉的需求,根據現(xiàn)有的農田灌溉裝備條件,應用領域作物、土壤、水源布點等情況,分析了目前實現(xiàn)精確農業(yè)亟待解決的關鍵技術問題,提出一套采用無線傳感器

12、網絡技術、適合大面積農田智能灌溉控制方法。</p><p>　　3.1　系統(tǒng)工作原理</p><p>　　研究單片機系統(tǒng)通過多個傳感器對濕度、溫度、降雨量、酸堿度、水分蒸發(fā)量(風速)和空氣溫度等多種信息的采集來實現(xiàn)對農田的精確自動灌溉控制,輸出的信號信息通過無線全雙工數(shù)傳收發(fā)模塊傳送給控制中心(嵌入式系統(tǒng))來確定是否啟動水泵為農田供水,同時將此供水與否信息由GPRS通信通過Internet

13、傳送到遠方控制中心實現(xiàn)遠程監(jiān)控,并通過計算機中的一些模型來處理信息,做出供水計劃。</p><p>　　3.2　無線傳感器網絡硬件設計</p><p>　　無線傳感器網絡模型是不同于傳統(tǒng)無線網絡的基礎設施網,通過在監(jiān)測區(qū)域內隨意布撒大量傳感器節(jié)點(簡稱節(jié)點),由各節(jié)點自行協(xié)調并迅速組建通信網絡,在能量利用率優(yōu)先考慮原則下進行工作任務劃分以獲取監(jiān)視區(qū)域信息。網絡的自組織特性體現(xiàn)在當節(jié)點失效或

14、新節(jié)點加入時網絡能夠自適應重新組建,以調整全局的探測精度,充分發(fā)揮資源優(yōu)勢,即網絡中的各節(jié)點除具備數(shù)據采集功能外兼有數(shù)據轉發(fā)實現(xiàn)多跳的路由功能。無線傳感器網絡每類節(jié)點的組成一般都由數(shù)據采集、數(shù)據處理、數(shù)據傳輸和電源這四部分組成。其中每一個單片機系統(tǒng)的硬件設計和軟件設計都是一樣。本設計的研究設計方案是只針對一個單片機系統(tǒng)的。被監(jiān)測物理信號的形式決定了傳感器的類型。處理器通常選用嵌入式CPU,如MOTOROLA公司的68HC16、C51系列

15、單片機等。數(shù)據傳輸單元可以選擇由低功耗、短距離的無線通信模塊組成,但考慮防盜與自然損壞,本系統(tǒng)選擇功耗較大、傳輸距離較遠的SA68D21DL,農民可以在辦公室或家中安放主控制器。圖2描述了節(jié)點的組成,其中,箭頭的方向表示數(shù)據在節(jié)點中的流動方向。</p><p>　　圖2　傳感器網絡框圖</p><p><b>　　3.3　主控系統(tǒng)</b></p><

16、;p>　　在該系統(tǒng)中,控制主機作為連接Internet網和無線傳感器網絡之間的協(xié)議轉換網關。其硬件采用致遠電子公司MiniARM嵌入式工控模塊。MiniISA系列采集板卡采用智能型板卡結構,即在板卡上內置MCU。板載MCU對板卡上I/O端口進行控制,實現(xiàn)I/O數(shù)據的緩存,從而降低板卡對于MiniISA接口主機的依賴,節(jié)省主機處理數(shù)據的時間,保證MiniISA系統(tǒng)更加高效的運行。此外板載MCU可以對采集的數(shù)據或者輸出數(shù)據進行進一步的

17、處理。系統(tǒng)電路圖如圖3所示。</p><p>　　圖3　主控系統(tǒng)結構圖</p><p>　　3.4遠程控制系統(tǒng)主要設計</p><p>　　GPRS通信系統(tǒng)、GPRS與Internet網絡接入系統(tǒng)、監(jiān)控中心主機友好界面顯示控制系統(tǒng)。這一部分硬件部分可以應用現(xiàn)有的移動公司與電信等互聯(lián)網資源,軟件考慮成本和專業(yè)功能可以自主開發(fā),建議應用現(xiàn)有遠程軟件,如《波爾遠程控制》軟

18、件、湖南省遠程監(jiān)控設備有限公司的RC-2000可視化遠程控制軟件系統(tǒng)。</p><p><b>　　結　語</b></p><p>　　本文綜述了無線傳感器網絡的節(jié)點構成、特點，以及當前在農業(yè)領域的應用,研究了基于嵌入式系統(tǒng)而設計出來的智能廣域農田供水系統(tǒng),當檢測到農田缺水信息時能夠通過自動控制繼電器來啟動供水水泵,而且實現(xiàn)了遠程GPRS通信,可以通過PC機來了解系統(tǒng)

19、的運行狀況并可對其控制,能夠自動采集土壤信息來自行確定是否啟動水泵為農田供水,這正符合我國農村的基本國情。本系統(tǒng)操作簡單,對系統(tǒng)改造一下,可以設計成庭院自動供水系統(tǒng)、溫室自動供水系統(tǒng)和花園自動供水系統(tǒng)等,故本系統(tǒng)的可擴展性比較好,前景比較廣闊。</p><p>　　無線傳感器網絡作為當今信息領域新的研究熱點，涉及多學科交叉。隨著傳感器成本的降低以及相關問題解決方案的不斷優(yōu)化，如能耗更加小和數(shù)據融合算法、節(jié)點定位算

20、法的不斷完善，以及更加優(yōu)秀的無線射頻模塊，無線傳感器網絡將會在農業(yè)領域有更廣泛的應用。</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.&