【正文】 產(chǎn)品具有成本低，體積小，傳輸速率快，點對點傳輸安全性好，不受電磁干擾等特點，可使得信息在幾個不同產(chǎn)品器件之間快速、便捷、安全地交換與傳輸。幾乎所有筆記本電腦、手機(jī)都配置紅外收發(fā)器接口。關(guān)鍵字：紅外線；編碼；解碼；LM386；紅外收發(fā)器。紅外數(shù)據(jù)通信技術(shù)在短距離無線傳輸領(lǐng)域內(nèi)有著十分顯著的優(yōu)勢。而且隨著交換的數(shù)據(jù)量變大，紅外數(shù)據(jù)通訊將使手機(jī)的數(shù)據(jù)傳輸越來越方便。只有一個指令信號傳輸通道的稱為單通道遙控系統(tǒng)。若想要實現(xiàn)任意一項的指定選擇控制 ,就需要采用多通道遙控系統(tǒng)。信號發(fā)送器可以用來產(chǎn)生遙控編碼脈沖，驅(qū)動紅外發(fā)射管發(fā)出紅外遙控信號。遙控收發(fā)系統(tǒng)一般由發(fā)射器和接收器兩部分組成。接收電路將發(fā)射器發(fā)射的調(diào)制完成的編碼指令信號接收下來 ,并進(jìn)行放大后輸入解調(diào)電路。而按芯片功耗大小區(qū)分的話又可以分為低功耗型和標(biāo)準(zhǔn)型兩類，低功耗型一般需要使用3V電源，傳輸距離比較近，約為030cm，標(biāo)準(zhǔn)型一般使用5V電源，傳輸距離比較遠(yuǎn)，最少可達(dá)1m以上。已經(jīng)開發(fā)出來的具備紅外通訊能力的設(shè)備已有一百多種，紅外模塊的年裝機(jī)量已達(dá)到了一億五千多萬套。其中如Agilent等公司還具有生產(chǎn)紅外收發(fā)器系列產(chǎn)品的能力，而HP、IBM等大公司則專門為自己公司產(chǎn)品配備紅外收發(fā)器。因此紅外遙控收發(fā)器產(chǎn)品還有很寬廣的發(fā)展前景。其中微米波長范圍內(nèi)又包括了紫外光、可見光、近紅外、中紅外、遠(yuǎn)紅外、微波。在近紅外區(qū)，它和可見光相鄰，因此具有可見光的某些特性，如直線傳播、反射、折射、散射、衍射、可被某些物體吸收以及可以通過透鏡將其聚焦等。因此紅外線的最大特點是普遍存在于自然界中，又叫做熱輻射線簡稱熱輻射。而紅外線的最長波長是最短波長的1倍，而紅外線的最長波長是最短波長的10倍，即有10個倍頻程。再由紅外光波的波長遠(yuǎn)小于無線電波的波長 ,所以紅外線遙控不會影響鄰近的無線電設(shè)備。這對于普及紅外線遙控提供了極大的方便。電子技術(shù)中是用紅外發(fā)光二極管（又稱紅外發(fā)射二極管）來產(chǎn)生紅外線。圖中的三極管作開關(guān)，當(dāng)基極上加有驅(qū)動信號時，三極管飽和導(dǎo)通紅外發(fā)光管D也正向?qū)üぷ?，發(fā)出紅外光（）。為了增加紅外線的控制距離，紅外發(fā)光二極管 D應(yīng)工作于脈沖狀態(tài)，即工作電流是脈動的。常見的紅外發(fā)光二極管，其功率分為小功率（1mW—10mW）、中功率（20mW－50mW）和大功率（50mW－100mW以上）三大類。直射式指發(fā)光管和接收管相對安放在發(fā)射與受控物的兩端，中間相距一定距離；反射式指發(fā)光管和接收管并列一起，平時接收管始終無光照，只在發(fā)光管發(fā)出的紅外光遇到反射物時，接收管收到反射回來的紅外線才工作。再接收到原信息后可在接收部分連接驅(qū)動電路以完成預(yù)期的各種功能。LOS方式是方向性的，它具有信道特性好等優(yōu)點，但存在“陰影”效應(yīng)，難于實現(xiàn)漫游功能。一方面采用各種方法提高光發(fā)射功率，另一方面采用空間分集、全息漫射片等使其光發(fā)射器的光功率空間分布均勻。紅外無線數(shù)字通信信道中常使用的光學(xué)元件主要有光學(xué)濾光片、聚光鏡等，它們的作用是:整形、濾波、視場變換、頻段劃分等，如可用透鏡對發(fā)射光進(jìn)行聚焦，利用光學(xué)濾光片濾除雜散光，利用透鏡擴(kuò)大光接收機(jī)的視場，還可利用光學(xué)元件進(jìn)行鏈路的頻分復(fù)用等。紅外無線光接收機(jī)常采用放大器，并要求為帶寬大、增益高、噪聲低、干擾小、頻率響應(yīng)與信道脈沖響應(yīng)匹配。頻率高，波長短，所發(fā)射的能量集中空間傳播時的衰減系數(shù)小，可保證信號的有效傳送；紅外線不能穿過或繞過人和物體，在數(shù)據(jù)傳輸時，不能阻斷光路； 前者以寬脈沖表示1，窄脈沖表示0。系統(tǒng)碼也叫識別碼，它用來指示遙控系統(tǒng)的種類，以區(qū)別其它遙控系統(tǒng)，防止各遙控系統(tǒng)的誤動作。地址碼和數(shù)據(jù)碼都用寬度不同的脈沖來表示，兩個窄脈沖表示“0”；兩個寬脈沖表示“1”；一個窄脈沖和一個寬脈沖表示“F”也就是地址碼的“懸空”。第三篇：電氣工程及其自動化專業(yè)英語翻譯Electric Power modern society depends on the electricity supply more heavily than ever can not be imagined what the world should be if the electricity supply were interrupted all over the power systems(or electric energy systems), providing electricity to the modern society, have bee indispensable ponents of the industrial first plete electric power system(prising a generator, cable, fuse, meter, and loads)was built by Thomas Edison – the historic Pearl Street Station in New York City which began operation in September was a DC system consisting of a steamenginedriven DC generator supplying power to 59 customers within an area roughly km in load, which consisted entirely of incandescent lamps, was supplied at 110 V through an underground cable system..Within a few years similar systems were in operation in most large cities throughout the the development of motors by Frank Sprague in 1884, motor loads were added to such was the beginning of what would develop into one of the largest industries in the spite of the initial widespread use of DC systems, they were almost pletely superseded by AC 1886, the limitations of DC systems were being increasingly could deliver power only a short distance from keep transmission power losses(I 2 R)and voltage drops to acceptable levels, voltage levels had to be high for longdistance power high voltages were not acceptable for generation and consumption of power。歷史上第一個完整的電力系統(tǒng)（包括發(fā)電機(jī)，電纜，熔斷器，計量，加載）由托馬斯愛迪生所建——紐約市珍珠街電站，始于1882年9月運(yùn)作。隨著弗蘭克斯普拉格在1884年對馬達(dá)的發(fā)展，電機(jī)負(fù)載被添加到這些系統(tǒng)，從此開始發(fā)展成為世界上最大的產(chǎn)業(yè)之一。為了保持發(fā)射功率損失（I 2 R）和電壓下降到可接受的水平，長途輸電電壓必須高。隨著交流的發(fā)展多相系統(tǒng)由尼古拉特斯拉，成為更具吸引力的。到了世紀(jì)之交時，下面的原因使交流系統(tǒng)贏過了直流系統(tǒng)：（1）交流系統(tǒng)電壓水平可以很容易地改變，從而提供了傳輸?shù)撵`活性，發(fā)電用不同的電壓和消費(fèi)。在電力傳輸初期交流頻率并不規(guī)范。較長的距離越來越需要大量的電壓傳輸這激勵了他們逐步使用高壓。第一個750 kVtransmission線將在不久的將來建在中國西北地區(qū)。由于電力無法用簡單和經(jīng)濟(jì)的方法大量儲存，電力的生產(chǎn)和消費(fèi)必須同時進(jìn)行。在電力系統(tǒng)的不穩(wěn)定可能會表現(xiàn)在經(jīng)營方式和多種不同的方式上，這取決于系統(tǒng)配置。第四篇：測繪專業(yè)英語論文外文翻譯The measurement of the surveying and mapping in mine Since the seventy s, as the electronic technology and laser technology development, the type of surveying and mapping instruments with electronics(such as range finder, electronic tachometer, gyroscopes)to the traditional surveying and mapping instruments methods produced profound satellite remote sensing, global positioning system, as a representative of the space on earth observation technology in surveying and mapping application in the science of mature, puter technology, system scientifically based geographic information system and application for the emergence of surveying and mapping information source of access, analyze, management, processing and application fully provide strong technical support, automation and intelligence of surveying and mapping system is already in investigation, therefore we can say, the modern mapping technology is undergoing a profound of measuring technology of an important application field, in the vast coal, metal mines, nonferrous mine production process played an important survey of modern task is: in mine exploration, design, development and production of the different stages of the operation of the ground and underground mining area, the space, resources,(in mineral and land resources and environment are mainly)information acquisition, storage, processing, display and use for reasonable and effective development resources, protecting the resources, protecting the environment, management, industrial and environmental services for the continuous development of the order to realize its modern task, mine measurement must be making full use of modern surveying and mapping instruments and techniques, put the advanced modern technology with mine surveying the actual work, specific characteristics, and the bination of broaden the living space mine survey and business scope, promote the reform and development of mine survey, adapt to the market economy system and mining system reform tachometer, space information technology, the inertial measurement system and other modern surveying and mapping instruments have been in mine survey technology is used to further development and are paper to modern surveying and mapping instruments of the development of the technology and its application in 、Electronic tachometer and its application in mine survey: Electronic tachometer as the most widely used surveying and mapping instruments, is electronic technology and optical technology development of