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

like this petrochemical plant --

比方是這座石油化學廠

you can't use RF, it may generate antenna sparks,

你不能用無線電,它有可能使天線爆出火花