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  • Do you know

    你知道

  • that we have 1.4 million cellular radio masts

    全世界手機通訊天線桿的數量

  • deployed worldwide?

    已達140萬

  • And these are base stations.

    這是基地台

  • And we also have

    此外

  • more than five billion

    還有50億以上

  • of these devices here.

    手持裝置

  • These are cellular mobile phones.

    也就是蜂窩手機

  • And with these mobile phones,

    手機的資料傳輸量

  • we transmit more than 600 terabytes of data

    每個月計算總共有

  • every month.

    600兆bits

  • This is a 6 with 14 zeroes --

    6後面加上14個0

  • a very large number.

    極大的數字

  • And wireless communications

    無線通訊

  • has become a utility

    已成為和水、電一樣

  • like electricity and water.

    的民生用品

  • We use it everyday. We use it in our everyday lives now --

    日常生活不可或缺

  • in our private lives, in our business lives.

    私人領域,商業領域

  • And we even have to be asked sometimes, very kindly,

    有時甚至必須非常客氣

  • to switch off the mobile phone at events like this

    才能請來賓暫將手機關機

  • for good reasons.

    譬如今天這裡的場合

  • And it's this importance

    它的重要性,促使我

  • why I decided to look into the issues

    決定探索這種技術

  • that this technology has,

    與之相關的幾個議題

  • because it's so fundamental to our lives.

    因它對大家都至關重要

  • And one of the issues is capacity.

    首先是承载量

  • The way we transmit wireless data is by using electromagnetic waves --

    我們用來傳輸無線訊號的是

  • in particular, radio waves.

    電磁頻譜中的無線電波

  • And radio waves are limited.

    無線電波的承载量有限

  • They are scarce; they are expensive;

    頻寬稀有,費用也貴

  • and we only have a certain range of it.

    能用的只有幾個波段

  • And it's this limitation

    這個資源和每個月

  • that doesn't cope

    手機傳輸資料量的需求

  • with the demand of wireless data transmissions

    根本難以

  • and the number of bytes and data which are transmitted every month.

    相提並論

  • And we are simply running out of spectrum.

    頻譜資源誠然已達枯竭

  • There's another problem.

    第二個麻煩是:

  • That is efficiency.

    效能

  • These 1.4 million cellular radio masts, or base stations,

    這140萬個手機基地台

  • consume a lot of energy.

    全都高秏電

  • And mind you, most of the energy

    更重要的是, 大部分所耗的電還不是用來

  • is not used to transmit the radio waves,

    打出無線電波

  • it is used to cool the base stations.

    而是用來冷卻基地台

  • Then the efficiency of such a base station

    每支基地台的效能

  • is only at about five percent.

    大約只有5%而已

  • And that creates a big problem.

    問題不小

  • Then there's another issue that you're all aware of.

    第三個問題,大家都注意到了

  • You have to switch off your mobile phone

    飛機上,醫院裡,會告知您「請關機」

  • during flights.

    這些場所,無可避免

  • In hospitals, they are security issues.

    因儀器操作安全性理由禁用無線電

  • And security is another issue.

    第4點,資料傳輸的安全性

  • These radio waves penetrate through walls.

    無線電波穿得透牆壁

  • They can be intercepted,

    有心人可以解碼

  • and somebody can make use of your network

    竊取你的資料,作非法用途

  • if he has bad intentions.

    竊取你的資料,作非法用途

  • So these are the main four issues.

    無線電波通訊總共有以上4個問題

  • But on the other hand,

    但另一方面,我們卻有

  • we have 14 billion of these:

    140億顆燈泡

  • light bulbs, light.

    燈泡代表:光資源

  • And light is part of the electromagnetic spectrum.

    光也是電磁頻譜的一部份

  • So let's look at this in the context

    我們就來看一下

  • of the entire electromagnetic spectrum, where we have gamma rays.

    整個電磁波頻譜中,最右邊

  • You don't want to get close to gamma rays, it could be dangerous.

    伽瑪射線,這個絕對要遠離,極端危險

  • X-rays, useful when you go to hospitals.

    X射線,上醫院才用

  • Then there's ultraviolet light.

    再來是紫外線

  • it's good for a nice suntan,

    曬出特定膚色很好用

  • but otherwise dangerous for the human body.

    否則對人體有害

  • Infrared --

    紅外線

  • due to eye safety regulations,

    由於眼部保健的原因

  • can be only used with low power.

    規定只能用低頻的部份

  • And then we have the radio waves, they have the issues I've just mentioned.

    最左是無線電波,剛說過它的瓶頸

  • And in the middle there, we have this visible light spectrum.

    在電磁波譜差不多中央地帶有個可見光的部份

  • It's light,

    也就是光

  • and light has been around for many millions of years.

    有地球的第一天就有光

  • And in fact, it has created us,

    事實上,光孕育了我們這些生命體

  • has created life,

    光創造了周遭萬千種種生命

  • has created all the stuff of life.

    光創造了周遭萬千種種生命

  • So it's inherently safe to use.

    當然是很安全可用的

  • And wouldn't it be great to use that for wireless communications?

    那為什麼我們不能用它來做無線電波傳輸呢?

  • Not only that, I compared [it to] the entire spectrum.

    不僅如此,當我拿它來和無線電波頻寬相比

  • I compared the radio waves spectrum --

    不僅如此,我還拿它來和無線電波頻寬相比

  • the size of it --

    比它們在光譜上的範圍大小

  • with the size of the visible light spectrum.

    在光譜上的範圍大小

  • And guess what?

    結果是:

  • We have 10,000 times more of that spectrum,

    光波段的頻譜要比無線電波寬了1萬倍!

  • which is there for us to use.

    只等著我們去開發使用!

  • So not only do we have this huge amount of spectrum,

    所以不只是頻寬很大可以去用

  • let's compare that with a number I've just mentioned.

    還有幾個數字也值得看一下做個比較

  • We have 1.4 million

    140萬座手機基地台

  • expensively deployed,

    低能源效益

  • inefficient radio cellular base stations.

    昂貴且低效益

  • And multiply that by 10,000,

    140萬 x 10,000

  • then you end up at 14 billion.

    =140億

  • 14 billion is the number of light bulbs installed already.

    140億正好是現有的燈具數量

  • So we have the infrastructure there.

    也就是說,基礎設施已經佈建完成!

  • Look at the ceiling, you see all these light bulbs.

    你們看吧,天花板,到處

  • Go to the main floor, you see these light bulbs.

    一樓大廳,都已經裝了很多燈泡

  • Can we use them for communications?

    我們可以用它來做無線通訊傳輸嗎?

  • Yes.

    可以

  • What do we need to do?

    怎麼做?

  • The one thing we need to do

    首先要把這個

  • is we have to replace these inefficient incandescent light bulbs,

    白熱光燈炮

  • florescent lights,

    並且不太節能的,日光燈炮

  • with this new technology of LED,

    改換成這個

  • LED light bulbs.

    LED燈泡

  • An LED is a semiconductor. It's an electronic device.

    LED是半導體產品,電子元件

  • And it has a very nice acute property.

    有著一個很棒的極端特性

  • Its intensity can be modulated

    它的密度可編碼轉換為高速資料流

  • at very high speeds,

    它的密度可編碼轉換為高速資料流

  • and it can be switched off at very high speeds.

    熄燈亮燈都可以高速進行

  • And this is a fundamental basic property

    我們的技術

  • that we exploit

    就是利用這個特性開發出來的

  • with our technology.

    接下來我們看看

  • So let's show how we do that.

    這種技術要怎麼做

  • Let's go to the closest neighbor to the visible light spectrum --

    先看在光譜上最近的隔壁鄰居

  • go to remote controls.

    遙控器

  • You all know remote controls have an infrared LED --

    大家都知道遙控器裡有個小LED燈泡,紅外線的

  • basically you switch on the LED, and if it's off, you switch it off.

    按一下遙控器它就開,再按一下就關

  • And it creates a simple, low-speed data stream

    它發出單一低速的資料流

  • in 10,000 bits per second,

    每秒10k bits

  • 20,000 bits per second.

    20k bits左右

  • Not usable for a YouTube video.

    用來傳youtube 影片是不可能的

  • What we have done

    但若用我們

  • is we have developed a technology

    開發出來的這種技術呢?

  • with which we can furthermore

    首先把這個遙控器裡的LED換掉

  • replace the remote control of our light bulb.

    換成加入了我們的技術的LED

  • We transmit with our technology,

    用它來傳,不只是單一資料流

  • not only a single data stream,

    用它來傳,不只單一資料流

  • we transmit thousands of data streams

    而是上千筆資料流

  • in parallel,

    平行,同步地傳

  • at even higher speeds.

    並且速度更快

  • And the technology we have developed --

    這種技術叫做

  • it's called SIM OFDM.

    SIM OFDM

  • And it's spacial modulation --

    是利用到第三維的「空間調變」技術

  • these are the only technical terms, I'm not going into details --

    技術細節在此點到為止

  • but this is how we enabled

    總之,我們應用這種技術來

  • that light source

    以光線

  • to transmit data.

    作無線傳輸用途

  • You will say, "Okay, this is nice --

    你會說,了不起

  • a slide created in 10 minutes."

    10分鐘就搞定的一個簡報,誰知道真假?

  • But not only that.

    所以,不只說說而已

  • What we've done

    我們做了

  • is we have also developed a demonstrator.

    一個現場示範機

  • And I'm showing for the first time in public

    這是首度在公開場合曝光的

  • this visible light demonstrator.

    一個可見光展示機台

  • And what we have here

    上面這是

  • is no ordinary desk lamp.

    一隻普通檯燈

  • We fit in an LED light bulb,

    裡頭改裝一顆LED燈泡

  • worth three U.S. dollars,

    價值美金3塊錢

  • put in our signal processing technology.

    燈泡裡面加上了信號處理技術

  • And then what we have here is a little hole.

    這裡有個小洞

  • And the light goes through that hole.

    檯燈的光穿過這洞

  • There's a receiver.

    抵達下面的接收機

  • The receiver will convert these little, subtle changes in the amplitude

    接收機將微小的振幅變化

  • that we create there

    -就是我們所賦予它的變化

  • into an electrical signal.

    轉換為電子訊號

  • And that signal is then converted back

    電子訊號又被轉換成資料流

  • to a high-speed data stream.

    高速資料流

  • In the future we hope

    未來我們希望能

  • that we can integrate this little hole

    將這個小洞

  • into these smart phones.

    整合到智慧手機裡

  • And not only integrate a photo detector here,

    不僅是整合一個光偵測器

  • but maybe use the camera inside.

    而可能是借用到裡面的照相模組

  • So what happens

    所以現在把燈炮打開

  • when I switch on that light?

    會發生什麼事?

  • As you would expect,

    當然啦,把書本攤開

  • it's a light, a desk lamp.

    在一盞燈底下,一定可以閱讀

  • Put your book beneath it and you can read.

    它是個燈

  • It's illuminating the space.

    燈泡有照亮環境的功能

  • But at the same time, you see this video coming up here.

    但同時它也在傳送一個影片

  • And that's a video, a high-definition video

    這個高解析度的影片

  • that is transmitted through that light beam.

    是透過光束傳送的

  • You're critical.

    或許你有點存疑

  • You think, "Ha, ha, ha.

    心裡想:哈哈,這只是

  • This is a smart academic doing a little bit of tricks here."

    一位聰明的大學教授在台上玩障眼法吧

  • But let me do this.

    不過,我證明給你看

  • (Applause)

    (掌聲)

  • Once again.

    還不相信的話

  • Still don't believe?

    再來一次

  • It is this light

    真的是這個光

  • that transmits this high-definition video in a split stream.

    在傳輸這支高解析度的影片,以分流的方式

  • And if you look at the light,

    所看到的光線

  • it is illuminating as you would expect.

    卻和你居家用來照明的光一樣

  • You don't notice with your human eye.

    肉眼察覺不出任何不同

  • You don't notice the subtle changes in the amplitude

    我們其實透過燈泡在這光裡壓縮了

  • that we impress onto this light bulb.

    一些極微小的振幅變化

  • It's serving the purpose of illumination,

    它既提供照明

  • but at the same time, we are able to transmit this data.

    同時也傳輸資料

  • And you see,

    即便天花板

  • even light from the ceiling comes down here to the receiver.

    有好多燈泡的光打下來在講台這邊

  • It can ignore that constant light,

    接收機卻可以忽略那些連續性光源

  • because all the receiver's interested in

    因為它只對

  • are subtle changes.

    有著特定的微小頻段變化的部分有反應

  • You also have a critical question now, and

    您或許還有些這樣那樣挑剔的問題

  • you say, "Okay,

    「那我們豈不是

  • do I have to have the light on all the time

    不能關燈啦

  • to have this working?"

    不然它就不工作了,是嗎?」

  • And the answer is yes.

    答案是:沒錯。

  • But, you can dim down the light

    不過,可以把燈光轉得很暗

  • to a level that it appears to be off.

    只要很暗就行,不用全關

  • And you are still able to transmit data -- that's possible.

    這樣資料還是會繼續傳輸,是可行的

  • So I've mentioned to you the four challenges.

    所以我已經跟各位介紹過四個無線通訊的瓶頸

  • Capacity:

    1. 承载量

  • We have 10,000 times more spectrum,

    有1萬倍的頻寬

  • 10,000 times more LEDs

    用LED的話

  • installed already in the infrastructure there.

    而其基礎設施已經是現成的

  • You would agree with me, hopefully,

    相信各位能同意我的看法:

  • there's no issue of capacity anymore.

    也就是,承载量不再是問題

  • Efficiency:

    其次,節能

  • This is data through illumination --

    這是運用燈具傳資料

  • it's first of all an illumination device.

    燈是基本一定要開的

  • And if you do the energy budget,

    這樣一來你算能源開銷時

  • the data transmission comes for free --

    資料傳輸項目等於免費

  • highly energy efficient.

    高節能,費用低

  • I don't mention the high energy efficiency

    還不提LED燈本身就是高度節能的燈具

  • of these LED light bulbs.

    要是全世界都改裝

  • If the whole world would deploy them,

    LED燈具的話

  • you would save hundreds of power plants.

    發電廠可以關掉幾百座

  • That's aside.

    那是題外話

  • And then I've mentioned the availability.

    繼續往下,可用性

  • You will agree with me that we have lights in the hospital.

    相信您必定同意,醫院也要開燈

  • You need to see what to do.

    否則就伸手不見五指啦

  • You have lights in an aircraft.

    飛機上也要開燈,照樣

  • So it's everywhere in a day there is light.

    到處都有燈光

  • Look around. Everywhere. Look at your smart phone.

    看一下,到處,包括智慧手機

  • It has a flashlight, an LED flashlight.

    還都裝上了手電筒,也是LED手電筒

  • These are potential sources for high-speed data transmission.

    全都是可以用來當做高速資料傳輸的設備

  • And then there's security.

    最後,資料內容安全性

  • You would agree with me

    這很簡單

  • that light doesn't penetrate through walls.

    光總不會穿透牆壁吧

  • So no one, if I have a light here,

    所以如果我在這裡

  • if I have secure data,

    用這光傳機密資料

  • no one on the other side of this room through that wall

    隔牆的人是不可能

  • would be able to read that data.

    讀得到這資料的

  • And there's only data where there is light.

    非要有光才能收資料

  • So if I don't want that receiver to receive the data,

    那要是我不想讓接收器收到資料

  • then what I could do,

    我可以

  • turn it away.

    把燈轉個頭

  • So the data goes in that direction, not there anymore.

    轉一個方向,資料朝向那邊,接收器就收不到了

  • Now we can in fact see where the data is going to.

    現在我們其實可以看到資料會去向哪個方向

  • So for me,

    對我而言

  • the applications of it,

    這個技術的應用

  • to me, are beyond imagination at the moment.

    是遠比想像的還美好

  • We have had a century of very nice, smart application developers.

    我們已有許多很棒的智慧產品應用開發商

  • And you only have to notice, where we have light,

    只要注意哪裏有燈

  • there is a potential way to transmit data.

    哪裡就有潛在應用

  • But I can give you a few examples.

    我可以跟各位講其中一些應用

  • Well you may see the impact already now.

    你現在已經可以看出其中一些影響力

  • This is a remote operated vehicle

    這是一艘遙控運輸器

  • beneath the ocean.

    在海底

  • And they use light to illuminate space down there.

    所以必須有燈光來提供照明

  • And this light can be used to transmit wireless data

    而這個燈就同時也能負責傳輸資料

  • that these things [use] to communicate with each other.

    這些運輸器彼此之間也就能通訊

  • Intrinsically safe environments

    極端要求安全的場所