200 years ago, it took 12 days to deliver a message from New York City to London.
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,
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” –
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?
When you tune a radio to a station, you pick up the information that is being sent out
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,
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,
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.
The network is a system of towers, antennas and transmitters which divide a geographical area into ‘cells’
– hence the term ‘cell phone’. These cells determine which areas are served by which towers,
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
and when moving at high speeds, like in a car, due to the frequent handover between network antennas.
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.
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.
If you‘’re out of range, or your phone is off,
the message is stored by the mobile switching center for a short time until you can be located by the network.
The network then figures out which tower you are closest to and passes the signal there.
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!
Now, most people send messages via internet services. In fact, last year WhatsApp overtook traditional SMS
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
that the technology for phones embedded in our bodies can be available as soon as 2023.
While only a few decades ago it may have taken months to send a love letter, in just a few
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,
how they%u2019re often misinterpreted, and how to use them properly.
Check it out with the link in the description!
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