Cellular, personal communication service (PCS), and third generation 3G mobile radio systems are all cellular wireless communication networks that provide for voice and data communication throughout a wide geographic area. Cellular systems divide ‘large geographic areas’ area into small radio areas (cells) that are interconnected with each other. Each cell coverage area has one or several transmitters and receivers that communicate with mobile telephones within its area.
The cellular system connects mobile radios (called mobile stations) via radio channels to base
stations. Some of the radio channels (or portions of a digital radio channel) are used for control
purposes (setup and disconnection of calls) and some are used to transfer voice or customer data
signals. Each base station contains transmitters and receivers that convert the radio signals to
electrical signals that can be sent to and from the mobile switching center (MSC). The MSC
contains communication controllers that adapt signals from base stations into a form that can be
connected (switched) between other base stations or to lines that connect to the public telephone
network. The switching system is connected to databases that contain active customers
(customers active in its system). The switching system in the MSC is coordinated by call
processing software that receives requests for service and processes the steps to setup and
maintain connections through the MSC to destination communication devices such as to other
mobile telephones or to telephones that are connected to the public telephone network.
stations. Some of the radio channels (or portions of a digital radio channel) are used for control
purposes (setup and disconnection of calls) and some are used to transfer voice or customer data
signals. Each base station contains transmitters and receivers that convert the radio signals to
electrical signals that can be sent to and from the mobile switching center (MSC). The MSC
contains communication controllers that adapt signals from base stations into a form that can be
connected (switched) between other base stations or to lines that connect to the public telephone
network. The switching system is connected to databases that contain active customers
(customers active in its system). The switching system in the MSC is coordinated by call
processing software that receives requests for service and processes the steps to setup and
maintain connections through the MSC to destination communication devices such as to other
mobile telephones or to telephones that are connected to the public telephone network.
When linked together to cover an entire metro area, the radio coverage areas (called cells) form a
cellular structure resembling that of a honeycomb. Cellular systems are designed to overlap each
cell border with adjacent cell borders to enable a “hand-off” from one cell to the next. As a
customer (called a subscriber) moves through a cellular system, the mobile switching center
(MSC) coordinates and transfers calls from one cell to another and maintains call continuity.
Key drivers for the mobile telephone market growth include new wireless technology (3G)cellular structure resembling that of a honeycomb. Cellular systems are designed to overlap each
cell border with adjacent cell borders to enable a “hand-off” from one cell to the next. As a
customer (called a subscriber) moves through a cellular system, the mobile switching center
(MSC) coordinates and transfers calls from one cell to another and maintains call continuity.
service availability and the replacement market for mobile phones with new capabilities such as
camera phones, color displays, and increased accessory capabilities.
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