Sistema de conmutación y control de llamadas basado en OpenBTS y Asterisk

Abstract

In the present research, some open source tools of hardware and software are used in order to build a free cellular base station BTS, of low cost and easy implementation, starting with an investigation of the technical concepts about the mobile systems, and the voice over IP VoIP technology. Then the installation of a system called OpenBTS is performed. This system uses the USRP hardware; a radio SDR defined software deploying a free GSM network, providing the communication with any phone that supports this standard. The system enables to switch it as a user agent of the session Initiation protocol SIP from Asterisk computer program. The latter software is installed as a VoIP PBX system with several modules to integrate a switching system where telephone calls are executed between registered users.