Getting the Terms Right
The term “cellphone” is interchangeable with the terms “cellular phone” and “mobile phone.” They all mean the same thing. The term “smartphone” means a cellphone that offers advanced features beyond calls, SMS messages, and basic organizer software. When people talk about mobile phones, “cellphone” is typically used to describe a simple feature phone. In contrast, “smartphone” describes advanced touch-screen phones.
History of Cellphones
Motorola developed the first commercially available cellphone between 1973 and 1983 and went on sale in the U.S. early in 1984. This giant 28-ounce cellphone, called the DynaTAC 8000x, cost $3,995 and needed to be charged after just 30 minutes of use. The DynaTAC 8000x is almost unrecognizable as a cellphone when compared to the devices we use today. It’s estimated that more than 6 billion cellphones (including smartphones) were in use at the end of 2020.
Cellular Networks
A cellular network, which gives cellphones their name, is comprised of cellular masts or towers distributed across the country in a grid-like pattern. Each mast covers a relatively small region of the grid, usually around 10 square miles, called a cell. Large mobile phone carriers, such as AT&T, Verizon, and T-Mobile, erect and use their own cellular towers and control the level of cellular coverage they can provide. Cellular providers don’t own all the land their towers are on; instead, large companies often lease the land from the owners. In turn, the large carriers often allow smaller regional carriers to use their towers for a fee. When you make a call on a cellphone, the signal travels through the air to the nearest mast or tower. Then it’s relayed to a switching network and finally on to the handset of the person you are calling via the mast closest to them. Suppose you’re making a call while traveling in a moving vehicle, for example. In that case, you may quickly move from the range of one cell tower to the range of another. No two adjoining cells use the same frequency to avoid interference, but the transition between cellular mast areas is usually seamless.
Cellular Coverage
In some countries, cellular coverage is available almost anywhere if you’re with one of the large national carriers—in theory. As you might expect, cellular coverage in highly populated areas is usually better than coverage in rural or sparsely populated areas. If you’re thinking of changing your carrier, research its coverage in your local area first. Cellular masts in cities are often close together, sometimes only a few hundred feet apart, because buildings and other structures can interfere with the signal. In open areas, the distance between masts may be several miles because there are no buildings or other structures to disrupt the radio waves. If the cellular signal is weak (rather than nonexistent), consumers can buy a cellular repeater or network extender, both of which can amplify and boost a weak signal.
