Here’s a goofy photo for ya, being a licensed Ham Radio guy for decades, I still have interest in all manner of radio communication. In a basic sense, your little device functions much the same as VHF and UHF two-way radios do. Your cell phone is actually a two-way radio which works via the cell towers which are the same thing as what we hams call a Repeater.
It’s a duplex system which transmits on a specific frequency on the Input side of the repeater, the repeater outputs the signal back to the ham radio on a different frequency. Your cell phone operates very much like the ham radio equipment does but with some fundamental differences. Now that you know a tiny slice of the Radio world, do you feel educated? It’s about electronics and simple physics!