How does my phone know which signals to catch from the millions of waves that transfer information in the air? Do they read all the information but process only the ones which are encrypted for me? Is the number if waves to different devices practically unlimited?
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Cellular networks are cellular, this means that you build ut up multiple cells. The radio waves that are used are nationally limited in range so you can reuse it one cell over, you can get the idea from [https://en.wikipedia.org/wiki/Cellular_network#/media/File:Frequency_reuse.svg](https://en.wikipedia.org/wiki/Cellular_network#/media/File:Frequency_reuse.svg) the reuse of frequencies and small cells is why there can be lot of cellphones used at one
So your phone could only receive signals from cell towers nearby. The signal is divided up into changes with a limited frequency range. The phone will filter out stuff that is not on that channel and only look at data on the channel it uses. You can compare it to how you tune a radio.
So the phone only looks at the data sent on the channel it uses, There will be data sent there that is for other phones too. I am not exactly sure how the radio signal is encoded on this level but it will have some structure.
So you have something like a receiver ID and length of the packet. So the pone can look at the ID and if it is not for them they can just ignore the length of the packet. So there is no need to look at all data sent in that channel just the one that is for you.
Technically phones uses CDMA where you decode the data intended for you from a stream with data to multiple phones but the general idea is still it is only a small part of the radio spectrum you listen to. The packet description above is more what WiFi use CDMA is just harder to understand and is not required to get for how you limit what you need to listen of at before that stage.
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