Kids’ Guide to Mobile Phones

How do mobile phones find the person you're calling?


That’s a good question. And the answer will show you that mobile phones are often working hard even between calls.

Mobile phones communicate by sending and receiving radio waves. Just like the waves created by dropping a stone into a pool of water, your mobile phone sends out radio waves in all directions.

Nexus 5

Then they’re picked up by your nearest base station, which is basically a big mast that can transmit and receive radio waves over much longer distances. This base station then sends radio waves which get carried across an enormous network until it reaches the person you want to call. But how do they find that person?

iphoneWell, your phone is constantly working – even when it’s not being used to make a call or access the internet – it’s constantly sending radio waves to your nearest base station. And in those radio waves are all sorts of important information like your country code and mobile number.

Each base station keeps a note of all the phones that are currently nearby. And they also communicate with other base stations, exchanging messages and information, through the network.

So when your phone dials a number, a message is sent over the radio waves to the nearest base station and a request is sent over the network to find your friend’s phone. The base station nearest to them connects with the nearest base station to you and the call is connected over the network. And since radio waves move at the speed of light, this all happens before you can say Techno Mum’s Techline.

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