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http://www.alltel.com/personal/cs/faq.html
"Satellite phone and Cellular phones are wireless devices. They almost look alike. But the way they work is totally different. Cellular phones working method is cell based. That is why they are called cellular phones. The whole network area is divided into small areas. And in each area an antenna is installed. These are also called towers. When a cellular phone is moving, it keeps entering from one cell to another. When it crosses the border of one cell, the phone sends a signal to the MTSO (Mobile Telephone Switching Office). With the help of control channel the database of the MTSO relocates the phone in a new cell or area. The MTSO and Public Switched Telephone Network (PSTN) coordinate to handle cellular calls.
But in the contrary Satellite phones use Low Earth Orbiting (LEO) satellites. With the turning on of the satellite phone a signal goes up to the any number of satellites of a group with whom the phone is registered. When a person makes a call from the handset, a signal goes to the near by orbiting satellite. The satellite connects to the gateway or ground station. Then the gateway takes the call to the destination. The call can be directed to the landline, cellular phone or PSTN. Any of the landlines, cell phone or PSTN can also call a satellite phone. In the case of satellite phones the gateway takes care of calls not cells as in the case of cellular phones. If a satellite phone calls another satellite phone, the call reaches a ground station through a satellite. Then it goes up to the air to a satellite and then the call reaches the destination phone. So the gateway processes the switching of calls not the satellite."
Satellite phone vs. all others
Linear Mode
