Satellite and cellular phones are wireless devices. They almost look alike but the way they work is totally different. A cellular phone functions on the basis of cells, and hence are called cell phones. The whole network area is divided into small areas and an antenna is installed in each area. These are also called towers. When a cellular phone is moving, it enters 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. Satellite phones use Low Earth Orbiting (LEO) satellites. When a satellite phone is turned on, a signal goes up to any number of satellites of a group the phone is registered with. When a person makes a call from the handset, a signal goes to the nearest orbiting satellite. The satellite connects to the gateway or ground station. Then the gateway takes the call to the destination.