Cell phones do not emit ionizing radiation, the type that damages DNA. Cellular phone technology works on a system of geographically separated zones called "cells. When a call is placed from a cellular phone, a signal is sent from the cell phone antenna to that cell's base station antenna. The base station responds to the cellular phone signal by assigning the phone an available radio frequency channel.
When the RF channel is assigned, modulated radio signals are simultaneously received and transmitted, allowing voice information to be carried between the cell phone and the base.
The base station transfers the call to a switching center, where the call can be transferred to a local telephone carrier or another cell phone. Cordless telephones , commonly used in homes, have base units that are plugged into telephone jacks and wired to local telephone service; these are not considered "cellular" phones. Transportable phones are also known as "bag phones.
Because they are most commonly stored inside the car with the phone user, or carried by the phone user, bag phones can be a greater source of RF exposure than mobile phones. Transportable telephone use is declining as portable phones become more popular. Mobile phones , also called "car phones," usually have an antenna mounted on the outside of a car-on the window, fender, roof, or trunk. With a cell phone, you can talk to anybody on the planet from almost anywhere.
But do you really know how your cell phone works? In the most basic form, a cell phone is essentially a two-way radio, consisting of a radio transmitter and a radio receiver.
When you chat with your friend on your cell phone, your phone converts your voice into an electrical signal, which is then transmitted via radio waves to the nearest cell tower. In the basic form, a cell phone works just like a walkie-talkie. In additional to the basic function of voice calls, most modern cell phones come with additional functions such as web surfing, taking pictures, playing games, sending text messages and playing music.
More sophisticated smart phones can perform similar functions of a portable computer. Cell phones use radio waves to communicate. Radio waves transport digitized voice or data in the form of oscillating electric and magnetic fields, called the electromagnetic field EMF.
The rate of oscillation is called frequency. Use a phone to call someone you haven't spoken to in a while. Catch up with them and let them know you care. You could even share with them some of the things you learned from today's Wonder of the Day! Sit down and have a discussion about phones with an adult friend or family member.
You might be surprised to learn about how many different types of phones they've used over the years. Do they remember ever using an old rotary dial phone?
Do they have any pictures of old phones they used to own? If not, jump online and look up pictures of old phones. Which ones do they remember using? How do they compare to today's phones?
Have fun on your trip down memory lane! Ready for a field trip! Ask an adult friend or family member to take you on a field trip to a local electronics store. Ask a salesperson to show you the range of phones available for sale. Do they still sell corded or cordless land line phones? How do those phones compare to the latest and greatest smartphones available?
Request a demonstration of the newest smartphone features. Talk with the salesperson about what changes they expect to see in phones in the future. Will they get bigger or smaller? What new features might they have? What features would you like to see in the next mobile phone? Did you get it? Test your knowledge. What are you wondering? Wonder Words roam data wave radio range tower digital coverage channel physical cellular smartphone transmitted recipient intermediate mobility frequency digitizing Take the Wonder Word Challenge.
Join the Discussion. Abby Hodge Feb 3, Feb 4, Ken Jan 31, I have always wondered about how some birds seem to breath under water i think they do at least. Feb 3, Alhiyona Oct 21, Oct 23, We do have a life away from Wonderopolis. Katelyn Feb 8, Hi wonderopolis! Feb 8, Brody Feb 5, Feb 6, Jocelyn Apr 24, Hi Wonderopolis, what is the universe made of? Apr 27, Potoes are people too Jan 24, Jan 24, I wonder how you can call even when your really far away.
Nov 14, Oct 5, Shatayah Mar 31, Apr 2, Wonderopolis Mar 16, Wonderopolis Mar 6, Wonderopolis Mar 2, Wonderopolis Feb 12, Hi, nneka! Jaheim Feb 10, I love touch screen they are the best thing that ever happen in the United States of America history.
Wonderopolis Feb 10, Welcome, Jaheim! It is amazing how phones and touch screens work. Thanks for commenting! Andrew Feb 10,
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