There are billions of mobile phones all communicating with each other sending wireless signals across the globe. How does each signal know where to go exactly, and how are they not intercepted by other signals?
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Radio signals from a mobile phone are broadcast in a sphere more or less in all directions. But the signal will only be handled by a designated cell tower, based on which one has the strongest reception. Encryption is usually used so that other devices can’t intercept the transmission. Once it reaches the tower it no longer needs to use radio waves, usually cables (copper or fibre optic) are used to transmit the call data to the destination (sometimes satellites may be used, which will be another radio signal).
At the receiving end, the cell tower nearest to the receiver will get the transmission via cable, and transmit the call to the phone via radio.
The telecommunications network knows which cell tower is closest to the phone because phones are constantly pinging nearby cell towers with their unique device identifier (IMEI) which is tracked by the network. The phone number you dial is matched to an IMEI, so the call can be transmitted to the nearest cell tower based on the last ping.
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