Cellular Network routing

Network routing in a cellular network deals with the challenges of traditional telephony such as switching and call setup. Most of the cellular network routing issues in different cells can be attributed to the multiple access methods used for transmission. The location of each mobile phone must be known to reuse a given band of frequencies in different cells and forms space-division multiple access(SDMA).

FDMA is one of the multiple access method used in cellular network and 50 MHz blocks of communication channel is assigned which lies in radio frequency range and contains equal number of uplinks(terminal to base station) and downlink(base station to terminal). One or more than one bidirectional channels are being carried by 10-90 band pairs. The digital networks on the other hand make additionally use of either code division multiple access or time division multiple access methods.

There is a special service called mobility management which provides this application. Terminals can move from one place to another during the call and therefore is not simple to continue the ongoing call from one channel to another which causes Handover. Call should not be dropped during the handover and changing from one service provider to another service. Soft handover uses same frequency channel rather than having quickly switch to an entirely different communication channel when communicating between different channels or base stations. The same terminals can operate in the same area covered by different service provider and is known as Roaming.

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