The practical experience of implementing a GSM BTS through open software/hardware

The objective of this paper is to show the implementation experience of a GSM Base Transceiver System (BTS) by using Universal Software Radio Peripheral, which is a multipurpose motherboard for Software Defined Radio (SDR), and a Personal Computer (PC). The OpenBTS project provides a software suite, created for the GNU Radio environment, and able to mimic the behavior of a GSM BTS. In order to allow GSM users to make calls and send text messages, it is necessary to operate some hardware modifications on the SDR motherboard, to set up a Session Initiation Protocol (SIP) server, to configure the server for providing connectivity between the mobile devices and the VoIP backhaul. In this paper, we will illustrate the needed software and hardware, and the steps necessary to create a small, cheap and autonomous GSM BTS.