What is Cellular Phone?
Cellular Phone and their Working
Cellular telephone or radio telephone is a type of mobile telephone which is integrated with existing telephone system, allowing mobile users to contact any one with a standard telephone and vice-versa. A cellular telephone network is setup by dividing the country into a series of cells, each with its own radio transmitter controlled by a central switching computer.
Each cell is about 5km. across and it brodcasts and receives low power signals on its own set of frequencies. There are at present three types of Cellular telephones. These are- Automobile based, Pocket or brifcase portables and transportables which can be moved in a vehicle and used in the hand.