How to page a person on a cell phone
When you speak into a cellphone, a tiny microphone in the handset converts the up-and-down sounds of your voice into a corresponding up-and-down pattern of electrical signals. A microchip inside the phone turns these signals into strings of numbers. The numbers are packed up into a radio wave and beamed out from the phone's antenna in some countries, the antenna is called an aerial. The radio wave races through the air at the speed of light until it reaches the nearest cellphone mast. Photo: Engineers repair a cellphone mast.
Fix problems with calls
The mast receives the signals and passes them on to its base station , which effectively coordinates what happens inside each local part of the cellphone network, which is called a cell. From the base station, the calls are routed onward to their destination. Calls made from a cellphone to another cellphone on the same network travel to their destination by being routed to the base station nearest to the destination phone, and finally to that phone itself.
Calls made to a cellphone on a different network or a land line follow a more lengthy path.
They may have to be routed into the main telephone network before they can reach their ultimate destination. At first glance, cellphones seem a lot like two-way radios and walkie talkies , where each person has a radio containing both a sender and a receiver that bounces messages back and forth directly, like tennis players returning a ball. The problem with radios like this is that you can only use so many of them in a certain area before the signals from one pair of callers start interfering with those from other pairs of callers.
- Calling services.
- Operator assistance.
- How do hackers steal cell phone numbers?.
- Pocket dialing - Wikipedia.
- Top rated tours!
- find people on the web free.
- Cybersecurity How to protect your cell phone number and why you should care – TechCrunch.
That's why cellphones are much more sophisticated—and work in a completely different way. A cellphone handset contains a radio transmitter, for sending radio signals onward from the phone, and a radio receiver, for receiving incoming signals from other phones. The radio transmitter and receiver are not very high-powered, which means cellphones cannot send signals very far. That's not a flaw— it's a deliberate feature of their design! All a cellphone has to do is communicate with its local mast and base station; what the base station has to do is pick up faint signals from many cellphones and route them onward to their destination, which is why the masts are huge, high-powered antennas often mounted on a hill or tall building.
If we didn't have masts, we'd need cellphones with enormous antennas and giant power supplies—and they'd be too cumbersome to be mobile. A cellphone automatically communicates with the nearest cell the one with the strongest signal and uses as little power to do so as it possibly can which makes its battery last as long as possible and reduces the likelihood of it interfering with other phones nearby. So why bother with cells?
- david eilers overton nebraska white pages?
- Calls from Your Own Phone Number | The Office of Attorney General Keith Ellison?
- How to Hold a Conference Call With Your iPhone!
- Use phone call options.
- Related Posts:.
- How to Remove Participants and Talk Privately!
- directory internet page phone switchboard yellow.
- recent narcotics arrests near dallas tx.
- Use Call Transfer to send calls to another phone | CenturyLink!
- lucas county ohio marriage license.
- Use FaceTime with your iPhone, iPad, or iPod touch;
- Make & receive phone calls - Phone app Help!
Why don't cellphones simply talk to one another directly? Suppose several people in your area all want to use their cellphones at the same time. If their phones all send and receive calls in the same way, using the same kind of radio waves, the signals would interfere and scramble together and it would be impossible to tell one call from another. One way to get around this is to use different radio waves for different calls. If each phone call uses a slightly different frequency the number of up-and-down undulations in a radio wave in one second , the calls are easy to keep separate.
They can travel through the air like different radio stations that use different wavebands. That's fine if there are only a few people calling at once. But suppose you're in the middle of a big city and millions of people are all calling at once. Then you'd need just as many millions of separate frequencies—more than are usually available. The solution is to divide the city up into smaller areas, with each one served by its own masts and base station.
These areas are what we call cells and they look like a patchwork of invisible hexagons. Each cell has its base station and masts and all the calls made or received inside that cell are routed through them.
10 awesome things you didn't know your phone could do
Cells enable the system to handle many more calls at once, because each cell uses the same set of frequencies as its neighboring cells. The more cells, the greater the number of calls that can be made at once. This is why urban areas have many more cells than rural areas and why the cells in urban areas are much smaller.
If a phone in cell A calls a phone in cell B, the call doesn't pass directly between the phones, but from the first phone to mast A and its base station, then to mast B and its base station, and then to the second phone. Cellphones that are moving between cells when people are walking along or driving are regularly sending signals to and from nearby masts so that, at any given time, the cellphone network always knows which mast is closest to which phone.
If a car passenger is making a call and the car drives between cells C, D, and E, the phone call is automatically "handed off" passed from cell to cell so the call is not interrupted. The key to understanding cells is to realize that cellphones and the masts they communicate with are designed to send radio waves only over a limited range; that effectively defines the size of the cells.
It's also worth pointing out that this picture is a simplification; it's more accurate to say that the masts sit at the intersections of the cells, but it's a little easier to understand things as I've shown them. The first mobile phones used analog technology. This is pretty much how baked-bean can telephones work too. When you talk on a baked-bean can phone, your voice makes the string vibrate up and down so fast that you can't see it. The vibrations go up and down like your voice. In other words, they are an analogy of your voice—and that's why we call this analog technology.
Use Call Transfer to send calls to another phone | CenturyLink
Some land lines still work in this way today. Most cellphones work using digital technology : they turn the sounds of your voice into a pattern of numbers digits and then beam them through the air. Using digital technology has many advantages. It means cellphones can be used to send and receive computerized data.
www.cantinesanpancrazio.it/components/vewurif/562-controllo-traffico.php That's why most cellphones can now send and receive text SMS messages, Web pages, MP3 music files , and digital photos. Digital technology means cellphone calls can be encrypted scrambled using a mathematical code before they leave the sender's phone, so eavesdroppers cannot intercept them. This was a big problem with earlier analog phones, which anyone could intercept with a miniature radio receiver called a scanner.
That makes digital cellphones much more secure. Cellphones have dramatically changed the way the world connects. In the early s, only one per cent of the world's population owned a cellphone; today, in a growing number of countries people spend more time on their mobiles than on their landlines. According to the ITU-T , in , only 58 percent of the world's population had access to a 2G cellphone network; by , that had risen to 98 percent.
By the end of , there were over 7. Cellphones have also powered a big leap in Internet access. At the end of , mobile smartphone and tablet Internet traffic passed desktop traffic for the first time ever. By the end of , 56 percent of the world's people had cellphone-based, broadband Internet access, which is over four times as many as have traditional wired broadband just 13 percent.
Chart: Cellphone subscriptions: The most dramatic cellphone growth has happened in developing countries, which now represent almost 80 percent of subscriptions. Cellphones are also used in different ways by different people. Back in the early s, cellphones were used entirely for voice conversations and sending short "texts" text messages, also known as SMS messages. A lot of people owned a mobile phone purely for occasional emergency use; and that still remains a popular reason for owning a phone according to the FCC , about 70 percent of all emergency calls in the United States are made from cellphones.
Today, smartphones are everywhere and people use them for emailing, browsing the web, downloading music, social media, and running all kinds of apps.
Where old-fashioned cellphones relied entirely on a decent signal from a cellphone network, smartphones hop back and forth, as necessary, between ordinary networks and Wi-Fi. Where old cellphones were literally "mobile phones" wireless landlines , modern smartphones are essentially pocket computers that just happen to make phone calls. If you want to find out how cellphone networks have evolved from purely voice networks to form an important part of the Internet, please see our separate article on broadband and mobile broadband. Photo: A simple, modern Nokia cellphone. New phones like this generally operate at lower power than older ones, producing less electromagnetic radiation and theoretically less risk to health.
People have been asking that question pretty much since cellphones first appeared—and the debate has intensified over the last decade or so. Why is it even an issue? As we discovered up above, cellphones communicate using radio waves, and we've all been bathing in massive doses of those things since radio and TV became popular in the early part of the 20th century. But the long-wave radio waves used in broadcasting are very different from the short-wavelength, high-frequency, high-energy radio waves at the opposite end of the electromagnetic spectrum.
Generally speaking, the shorter the wavelength of radio waves the more dangerous they are to our health. That's why we take great care with the safety of microwave ovens and X ray machines.
The trouble with cellphones is that they use waves that are on the border between the safer, long-wavelength radio waves and the unsafer, short-wavelength ones. Although the waves they use are defined as microwaves, they're longer wavelength, lower frequency, and lower energy waves than the ones used in microwave ovens. Where a microwave oven can produce perhaps watts of cooking power, a cellphone makes fractions of a watt at most—thousands of times less, in other words. So do cellphones "cook your brain" or "give you cancer"? It's very difficult to answer that question conclusively.