The Research On Unauthorized Access To The GSM System

This paper chiefly deals with some elementary and essential technique problems on unauthorized access to GSM system. These problems concentrate on the physical layer and data link layer of GSM system. Some technical details involved in this paper are author's explorative research. Although this paper does not authenticate whether the technical details are consistent with the telecom service provider's, its finial conclusion has been approved correct. In detail, the achievements of research are focused on several aspects as follows: first, the framework of physical and data link layers of GSM system is analyzed; Second, a GSM signal receiving and analyzing platform, composed of dual A/D data collection board, mobile station and computer, is designed and implemented; Third, the entire working procedure of platform is simulated with MATLAB Language, and partial signaling information has been successfully demodulated. Therefore, the main technique problems on unauthorized access to GSM system are settled in this paper. In addition, the security of GSM system is discussed in this paper, and its relevant security measures and amendatory ideas are also put forward.