So like, when I speak into my phone while on a call, whats the process before it gets sent out to the other person? Like my voice has to be turned into a digital signal somehow? And how does what software understand any of that?
In: 25
Depends what technology you’re using for the small steps, but in the big picture, your voice is an analog signal that gets turned into digitized PCM stream. It is down sampled to 8000 Hz first (landline quality, though VoLTE is 22500Hz or even 44100Hz, closer to music quality) then fed into a codec to compress it to with a ratio of 30:1 to 15:1 (for comparison, streaming music with good quality is 10:1 or higher and sampled at 44100Hz). Basically, taking the audio stream, removing extraneous and unnecessary noise/signals, and producing a much smaller data stream to send to the tower.
Once it is submitted to the tower, the digitized stream traverses the carrier’s network until it reaches the Public Switched Telephone Network or another carrier’s gateway, routed on that destination network, and the process is reversed then encoded with that network’s technology to be transmitted to the other party’s receiver.
Edit: forgot to say the call is off course encrypted to the tower
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