As mobile technology continues to advance, it can be hard to imagine a life without it. From smartphones to tablets, laptops, and even some cars, mobile devices can help us work remotely, connect with family and friends, access education online, and stay up-to-date on the latest news and trends in our industries. In fact, according to this chart, the number of smartphone users has surpassed 3 billion worldwide.
One of the most important things to understand about mobile technology is that, at its core, a cellphone is essentially a radio. In fact, wireless communication technologies can trace their roots all the way back to Alexander Graham Bell’s invention of the telephone in 1876 and Nikolai Tesla’s development of the radio in the 1880s.
Cellphones transmit by sending signals over a network of base stations, which cover the entire globe. These base stations are separated into uniform areas of coverage, known as cells. If multiple cellphones try to use the same frequencies at the same time, they would interfere with each other and make it impossible to tell one call from another. To prevent this, each cellphone transmits using a different frequency than the others in its cell.
When you’re on the move, your phone has to keep re-associating with these cells to maintain a connection. When it reaches the edge of one cell, your device’s base station notes that the signal is weakening. Then, it coordinates with the base stations in the next cell on a control channel and hands off your phone to them. The new cell then picks up your signal and starts transmitting on its own frequency.