最新评论 (0)


Where Do Your Texts Go?

在200年前 从纽约市到伦敦的通信需要花上12天
200 years ago, it took 12 days to deliver a message from New York City to London.
150年前 第一条跨太平洋海底电报从英女王传到美国总统
150 years ago the first transatlantic cable transmission was sent from the Queen of England to the US President,
一共花了17小时 85年前 电话变成了家庭的标配
taking 17 hours. 85 years ago, telephones became common household fixtures
然后30年前 移动电话首次面世 这部大哥大重得像一块砖
and 30 years ago the first cell phone was invented, which weighed as much as an iron,
充电10小时通话35分钟 造价将近4000美金
took 10 hours to charge for a 35 minute conversation, and cost almost $4000.
20 years ago, the first text message was sent – a simple “Merry Christmas” –
如今持手机的人比厕所还要多 每天共收发约230亿条短信
and today more people have mobile phones than toilets, with around 23 billion text messages being sent per day.
But how the hell do text messages even work?
收音机调电台时 你所收到的信息
When you tune a radio to a station, you pick up the information that is being sent out
来自于特定频率的电磁波 具体来说是无线电波
via electromagnetic waves at a particular frequency – in this case they are radio waves.
These waves mostly just pass through our bodies without interacting at all,
它们和可见光都是光谱的一部分 只是波长不同
but are on the same spectrum as the visible light we see, just different in size.
Photons with wavelengths between 400-700 nanometers have the perfect level of energy to excite the rods and cones in your eyes,
which then transmit signals to your brain that you interpret as different colours.
But radio waves, which have wavelengths ranging from 100 microns to 100 kilometers,
能量太低刺激不了视细胞 因此我们是看不见的
are much lower energy and can’t excite your eyes – so they are invisible to us.
Similar to a radio, your cell phone receives signals at specific frequencies,
but it can also transmit its own radio waves back to a network at the same time.
移动网络由一系列的信号塔 天线和发射器组成它们把地域分割成“蜂窝”
The network is a system of towers, antennas and transmitters which divide a geographical area into ‘cells’
因此也叫作蜂窝网络 这些蜂窝决定了哪些信号塔负责哪些区域
– hence the term ‘cell phone’. These cells determine which areas are served by which towers,
不过区域也会有所重合 因此手机总能和信号塔通讯
though they generally overlap so that your phone always has a tower to communicate with.
Feel like your phone battery is losing power faster than normal?
Phones transmit at higher levels indoors due to building materials,
in rural areas due to greater distance to the network antennas
乘车高速移动时 手机会频繁在不同天线之间切换
and when moving at high speeds, like in a car, due to the frequent handover between network antennas.
其他人给你发短信时 她们的手机会发出无线电波
Whenever someone sends you a text, their phone transmits radio signals,
which convey the identity of both their phone and yours, along with the content of the message.
这些信号传到最近的通信塔中 便会从电波被转变成数码格式
These signals are then picked up by the tower closest to them, which converts the radio waves into a digital electrical impulse
and passes it along to a hub of the network called a mobile switching center.
如果你在服务区外 或者手机关机了
If you‘’re out of range, or your phone is off,
短信将暂时存在移动交换中心 直到你再次进入网络
the message is stored by the mobile switching center for a short time until you can be located by the network.
然后移动网络就会为你找到最近的信号塔 并从那里为你发信
The network then figures out which tower you are closest to and passes the signal there.
信息到了最近的信号塔便会被转成电波 再被手机天线所接收
Once at the tower nearest you, it’s converted back to a radio signal that can be picked up by the antenna in your phone.
This all happens in SECONDS!
Interestingly, traditional SMS text traffic actually peaked in 2011!
现在大多数人改用互联网来发信息 去年WhatsApp超过了传统的SMS
Now, most people send messages via internet services. In fact, last year WhatsApp overtook traditional SMS
成为文字短信的第一大头 在全球每天收发300亿条信息
as the #1 handler of text messaging, managing 30 billion messages sent each day all over the world.
And if you%u2019re sending those messages across the world,
it’s actually sent via a giant cable that runs across the ocean floor.
In fact 99% of all international data is sent via undersea cables.
So what does the future of messaging look like? We%u2019re currently in the 4th generation
of mobile communication networks, with 5G on the horizon. And it%u2019s actually been projected
甚至有人预测道 人和手机一体化的技术最早在2023年就能问世
that the technology for phones embedded in our bodies can be available as soon as 2023.
几十年前 一封情书要好几个月才能寄到
While only a few decades ago it may have taken months to send a love letter, in just a few
而在若干年之后 也许你只要在脑中想起你爱的人
years you may be able to simply think of your loved one and send them a message to let them
know you care.
We tackle humanity’s new forms of communication in The Science of Emojis over on AsapTHOUGHT,
有哪些常见的误解 应该如何正确使用呢
how they%u2019re often misinterpreted, and how to use them properly.
Check it out with the link in the description!
想关注每周科普视频的话 请订阅这个频道
And subscribe for more weekly science videos.