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S T E M I N C U R R E N T E V E N T S
However, engineering generally refers to “big picture” technol-
ogy, such as networks, towers, and systems, rather than smaller
consumer devices, such as cell phones.
Mobile Phone Networks and Towers
While amobile phone’s ability to transmit voice and data via radio
waves is a great idea, if those radio waves don’t meet up with a
receiver, they’ll never make it to their intended destination. Cell
towers are needed to capture the radio waves from individual
mobile phones and transmit them to their recipients.
Connecting cell towers and networks is an immense engineer-
ing problem for a number of reasons. Radio waves can techni-
cally pass through walls and other barriers, but the quality of
the transmission deteriorates. The purpose of a tower is to rise
above an area so that there’s a clear line of sight with as many
cell phones as possible.That reduces the risk of dropped signals
or bad connections. Since towers have limited range, enough
towers have to be constructed so that as a mobile phone moves
out of range it easily finds a new tower to continue its connec-
tion. This process is known as a “hand-over” and is processed
by the switching center attached to the base of every cell tower.
Well-engineered towers make these switches seamless to the
point that you’re unlikely to know when your call has changed
towers. The entire system of cell towers and switching centers
is an engineering marvel—but those times may be a-changing.
Steve Papa, founder of Parallel Wireless, envisions a near-term
future in which massive cell towers become relics of the past.