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1、<p>  附錄A 外文文獻(xiàn)及翻譯</p><p>  How Remote Controls Work</p><p>  by Julia Layton</p><p>  from: http://electronics.howstuffworks.com/remote-control.htm</p><p>  Introd

2、uction to How Remote Controls Work</p><p>  The world's first remote controls were radio-frequency devices that directed German naval vessels to crash into Allied boats during WWI. In WWII, remote contro

3、ls detonated bombs for the first time. The end of the great wars left scientists with a brilliant technology and nowhere to apply it. Sixty years later, some of us spend an hour looking for the remote before we remember

4、there are buttons on the TV. </p><p>  In this article, we'll examine the infrared technology used in most home theaters, look at the difference between IR and RF remotes, find out the difference between

5、 a "universal" and a "learning" remote and check out some of the other high-tech features you can find on remotes today, like PC connectivity, RF extenders and macro commands.</p><p>  In

6、frared Remote Controls: The Process</p><p>  Pushing a button on a remote control sets in motion a series of events that causes the controlled device to carry out a command. The process works something like

7、this: </p><p>  1. You push the "volume up" button on your remote control, causing it to touch the contact beneath it and complete the "volume up" circuit on the circuit board. The integr

8、ated circuit detects this. </p><p>  2.The integrated circuit sends the binary "volume up" command to the LED at the front of the remote.</p><p>  3.The LED sends out a series of light

9、 pulses that corresponds to the binary "volume up" command. </p><p>  One example of remote-control codes is the Sony Control-S protocol, which is used for Sony TVs and includes the following 7-bit

10、 binary commands:</p><p>  The remote signal includes more than the command for "volume up," though. It carries several chunks of information to the receiving device, including: </p><p&g

11、t;  ?a "start" command </p><p>  ?the command code for "volume up" </p><p>  ?the device address (so the TV knows the data is intended for it) 、</p><p>  ?a &quo

12、t;stop" command (triggered when you release the "volume up" button) </p><p>  So when you press the "volume up" button on a Sony TV remote, it sends out a series of pulses that looks

13、 something like this: </p><p>  Sony TV remotes use a space-coding method in which the length of the spaces between pulses of light represent a one or a zero.</p><p>  When the infrared receiver

14、 on the TV picks up the signal from the remote and verifies from the address </p><p>  code that it's supposed to carry out this command, it converts the light pulses back into the electrical signal for

15、001 0010. It then passes this signal to the microprocessor, which goes about increasing the volume. The "stop" command tells the microprocessor it can stop increasing the volume. </p><p>  Infrared

16、 remote controls work well enough to have stuck around for 25 years, but they do have some limitations related to the nature of infrared light. First, infrared remotes have a range of only about 30 feet (10 meters), and

17、they require line-of-sight. This means the infrared signal won't transmit through walls or around corners -- you need a straight line to the device you're trying to control. Also, infrared light is so ubiquitous

18、that interference can be a problem with IR remotes. Just a f</p><p>  While infrared remotes are the dominant technology in home-theater applications, there are other niche-specific remotes that work on radi

19、o waves instead of light waves. If you have a garage-door opener, for instance, you have an RF remote. </p><p>  Remote-control Features</p><p>  Today's home-theater remotes do a lot more t

20、han turn a component on and off and control the volume. Here are just a handful of the features you can find on some of the higher-tech remote controls out there. </p><p>  Universal capabilities</p>

21、<p>  Different electronics brands use different command codes. Some IR remotes are preprogrammed with more than one manufacturer's command codes so they can operate multiple devices (sometimes up to 15) of diff

22、erent brands. If your home-theater setup incorporates components from, say, three different manufacturers, you can either use three different remotes to operate your system or use one universal remote. To add functions t

23、o a universal remote, you need to know the command codes for the component </p><p><b>  Learning</b></p><p>  A learning remote can receive and store codes transmitted by another rem

24、ote control; it can then transmit those codes to control the device that understands them. For instance, let's say you have a receiver with its own preprogrammed remote, and you buy a new TV that comes with a univers

25、al learning remote. The learning remote can pick up the signals your receiver remote sends out and remember them so it can control your receiver, too. You don't need to input the command codes yourself -- a learn<

26、/p><p>  Macro commandsA macro is a series of commands that you program to occur sequentially at the push of a single button. These macros can be anything you want, such as an "activity command." You

27、 can set up a macro that lets you push one button to activate, in order, everything that needs to happen for you to watch a movie or listen to a CD. (Some remotes come with "activity commands" preprogrammed, an

28、d others let you download macros from the Internet.) </p><p>  PC connectivity</p><p>  There are remotes that connect to your PC via the USB port so you can install programming software and dow

29、nload command codes and personalized graphic icons (for remotes with LCD screens). </p><p>  LCD screen</p><p>  A remote-control LCD screen may simply display data, or it may be a touchscreen t

30、hat receives user input. </p><p>  User interfaces</p><p>  Most remotes still utilize the simple button-pushing method, but some have more high-tech manners of inputing commands. You'll fin

31、d remotes that you operate via an LCD touchscreen, a joystick (for directional commands) and even voice commands. </p><p>  RF extendersSome IR remotes can send out both IR and RF signals. The RF signals ar

32、en't meant to control RF devices (in fact, they can't control them). They're meant to extend the operating range of the IR remote control from about 30 feet to about 100 feet (give or take) and allow the sign

33、al to penetrate walls and glass cabinet enclosures. The remote automatically transmits both IR and RF signals for every command. When you hook up an RF-to-IR converter (sometimes included with IR/RF remotes, s</p>

34、<p>  Remote controls are steadily increasing the number of devices and functions they can manage. Some universal remotes intended for home-theater components can learn commands for wirelessly controlled lights, so

35、 they will not only start a movie at the push of a button, but they'll also dim the lights for you. Full home-automation systems let you use one remote control to manage lighting, alarm systems and entertainment comp

36、onents by way of a receiver wired directly into your home's electrical wirin</p><p><b>  無線遙控器怎樣工作</b></p><p>  Julia Layton 著</p><p><b>  紅外遙控工作原理</b>&l

37、t;/p><p>  世界上第一個(gè)無線遙控器是在一戰(zhàn)中以發(fā)射無線電波來指引德國海軍摧毀盟軍的船只。 在一戰(zhàn)中,無線遙控器能使炸彈在第一時(shí)間爆炸,現(xiàn)在,在戰(zhàn)爭(zhēng)中幸存的科學(xué)家用其出色的技術(shù)使無線遙控?zé)o處不在。在我們花一小時(shí)來尋找遙控器前我們都記得有按鈕在電視上。</p><p>  在這片文章中,我們將介紹紅外遙控在家庭影院中的應(yīng)用,尋找紅外遙控和射頻遙控的區(qū)別,找出“普通型”和“學(xué)習(xí)型”無線遙控

38、的區(qū)別。找出其他一些高科技含量的遙控技術(shù),例如用無線射頻技術(shù)遙控電腦。</p><p><b>  紅外遙控的方法</b></p><p>  按下遙控器的按鈕會(huì)發(fā)射一連串的代碼來使被遙控器件按照代碼的命令動(dòng)作。</p><p><b>  這個(gè)工作過程如下:</b></p><p>  1.你按下

39、遙控器的“音量增加”鍵,按鍵下面的與“音量增加”的電路接通,電路檢測(cè)到連接。</p><p>  2.電路將二進(jìn)制的“音量增大”命令傳送給發(fā)光二極管。 </p><p>  3.發(fā)光二極管發(fā)射一系列的光脈沖來發(fā)送:音量增大“命令。</p><p>  已sony公司的遙控編碼方式為例,其用于控制sony公司的電視機(jī),光脈沖命令中包含的7位二進(jìn)制碼如下:</p&

40、gt;<p><b>  表A1</b></p><p>  無線信號(hào)不僅僅只包含“音量增大“的命令,它還向接收裝置發(fā)射其它幾個(gè)部分的信息。</p><p><b>  包括:</b></p><p><b>  ??“開始”碼</b></p><p>  ?“音

41、量增大”命令碼</p><p>  ?地址碼(電視可以區(qū)分出正確的信號(hào))</p><p>  ?“停止”碼(當(dāng)松開“音量增大”鍵時(shí)發(fā)射)</p><p>  因此當(dāng)你按下sony電視的遙控器時(shí),它會(huì)發(fā)射一些列的脈沖如下圖所示:</p><p><b>  圖A1</b></p><p>  注:S

42、ony的電視遙控信號(hào)用占空比的方法來通過區(qū)分脈沖長(zhǎng)度來得到紅外信號(hào)中的0和1。</p><p>  當(dāng)電視上的紅外接收器接收到遙控信號(hào)并且核對(duì)地址碼無誤后就會(huì)執(zhí)行相應(yīng)命令。就會(huì)將光脈沖轉(zhuǎn)換為001 0010的二進(jìn)制電信號(hào),然后將這個(gè)二進(jìn)制信號(hào)傳給微處理器。微處理器就會(huì)將音量增大?!巴V埂贝a將使微處理器停止增大音量。</p><p>  紅外遙控已經(jīng)可靠的應(yīng)用了25年,但是紅外線自身具有一些

43、局限性。首先,紅外遙控的遙控距離只有30英尺,還需要視線,也就是說紅外信號(hào)不能穿過墻壁或者看不到的地方。如果你要進(jìn)行遙控你就要對(duì)準(zhǔn)設(shè)備,并且我們周圍普遍存在著各種紅外線因此會(huì)產(chǎn)生干擾問題。紅外線的來源包括陽關(guān)、日光燈和人體。為了避免紅外線之間的干擾,電視機(jī)上的紅外接收器只對(duì)一種波長(zhǎng)的紅外線做出反應(yīng)。通常為980納米的波長(zhǎng)。在接收器上有一個(gè)過濾器能將其他波長(zhǎng)的紅外線過濾掉。因?yàn)樘柟獍?80納米波長(zhǎng)的紅外線,所以依然會(huì)干擾接收器。為了解

44、決這一問題,會(huì)將紅外遙控器發(fā)射的紅外線調(diào)制到太陽光沒有的頻率上,然后紅外接收器只對(duì)980納米并且經(jīng)過調(diào)頻后的紅外線做出反應(yīng)。用這種方法做成的遙控系統(tǒng)雖然并不完美,但是卻是減少了很多干擾。</p><p>  在紅外遙控在家庭影音領(lǐng)域占據(jù)主導(dǎo)之時(shí),基于無線電波的遙控技術(shù)在一些地方取代了紅外遙控。如果你有一個(gè)車庫開關(guān),你就可以看到無線電遙控的例子。</p><p><b>  遙控技

45、術(shù)的特殊應(yīng)用</b></p><p>  今天對(duì)家庭影音設(shè)備的遙控已不僅僅是控制其開、關(guān)和調(diào)節(jié)聲音大小。下面是一些遙控技術(shù)在該科技領(lǐng)域的特殊應(yīng)用。</p><p><b>  ◆全面的遙控能力</b></p><p>  不同的電子廠商使用不同遙控代碼,一些紅外遙控器能發(fā)射不止一種的遙控代碼,因此可以操作多種品牌的設(shè)備工作,一些最多

46、可以操作15種不同品牌的設(shè)備工作。如果你的家庭影音系統(tǒng)有好幾個(gè)遙控部分組成,比如說有三個(gè)部分,你既可以用三個(gè)遙控器去操作你的系統(tǒng),也可以使用一個(gè)多功能遙控器。如果要給多功能遙控系統(tǒng)增加功能,你得先知道這個(gè)設(shè)備能接受的遙控代碼格式,這些設(shè)備能接受的遙控代碼格式你可以自己在網(wǎng)上找到。</p><p>  ◆自學(xué)能力自學(xué)遙控器可以接收并且記下另一個(gè)遙控器代碼格式,然后可以發(fā)射這種代碼格式的代碼去控制能夠識(shí)別這種代碼的

47、設(shè)備。例如,你有一個(gè)設(shè)備只接收一種遙控代碼,然后你買了一個(gè)配有自學(xué)遙控器的電視,自學(xué)遙控器就會(huì)接收并且記下你的設(shè)備接收的遙控信號(hào),然后你也可以用自學(xué)遙控器去控制這個(gè)設(shè)備,你不用自己去輸入遙控代碼,自學(xué)遙控器就會(huì)自己接受并存儲(chǔ)另一個(gè)遙控器的遙控信號(hào)。因?yàn)樽詫W(xué)遙控器不知能控制一個(gè)設(shè)備,所以所有的自學(xué)遙控器都可以被認(rèn)為是全能遙控器。</p><p><b>  ◆與電腦連接性</b></p&

48、gt;<p>  有些遙控器可以通過USB接口和電腦連接,只要你安裝了專門設(shè)計(jì)的軟件</p><p>  和下載到該遙控的命令代碼,你就可以自己對(duì)設(shè)置遙控器進(jìn)行人性化的遙控。</p><p><b>  液晶屏幕</b></p><p>  使用液晶屏顯示的遙控器經(jīng)更加直觀的顯示數(shù)據(jù),或許在不久還可以使用觸</p>

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