Cellphone technology is progressing rapidly and changing the face of communications. So,
it’s important to understand how a cellphone works.
Cellphones are actually radios. They interface with the network, in a full-duplex system,
to transmit and receive radio signals. Full-duplex means that there are separate channels sending
and receiving information; so people can talk and listen to someone else simultaneously.
This is in contrast to things, like walkie-talkies, that are half-duplex where you can’t hear
the other person if you’re talking.
The network consists of low-powered radio antennas and transmitters arranged in cells.
A cell is a certain, geographic location that is served by a particular tower. If you are
moving, your cellphone signal is transferred from cell to cell, depending on your location,
in order to prevent you from losing the call.
All of these cells are connected to a mobile switching center. Signals are passed from
the phone, through the antenna, and sent through the switching center where they will either
be passed to another cell or converted to a signal that can be sent along traditional
telephone lines.
The entire, complicated process only takes a second to complete. Maintaining the system
is very important to keeping the lines of communication open.