GSM Landline Switch

Abstract

A switch has been designed to integrate land line number and 4 GSM SIM modules.It achieves the cost effectiveness by using the idea of the call between the homogenous and heterogeneous networks. It comprises of landline number, GSM landline switch which includes pic microcontroller 18F452 interfaced with the DTMF Decoder and 4xMultiplexers, 4xSIM modules for communication with the BTS. The cost reduction is achieved by converting the fixed to mobile call into mobile to mobile call. Interface between the landline call and the GSM network is given by GSM landline switch after reading the first four digits of the dialed number and routing it to the suitable service provider which is homogenous network. GSM network is acquired through the SIM modules of different service providers and landline number from Pakistan Telecommunication Limited. Pic Microcontroller 18F452 is programed in micro C language.