Cell Phones

This passage describes how cell phones work.

Lexile Level: 1120L

Categories: Science & Technology

Cell phones are not really phones, but rather radios. However, cell phones work differently from other forms of radio communication, such as walkie-talkies and CB radios. When two people speak on walkie-talkies, they communicate on the same radio frequency. For this reason, only one person can speak at a time. It is common to say the word "over" when speaking on a radio so the listener knows that he or she can now respond to what was said. Cell phones, however, use two frequencies, one for speaking and one for listening. This enables two people to speak at the same time when engaging in a cell phone conversation. Another feature of cell phones is that they utilize "cells" within the range of a tower and during conversations, the cell phone can move from cell to cell and tower to tower without interfering with communication. This gives the cell phone much greater range than most other forms of radio communication.

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