Software Defined Radios και υλοποίηση τεχνικών ασφαλείας φυσικού στρώματος
This thesis elaborated within the framework of completion of University of Piraeus Postgraduate program «Digital Communications and Networks» in order to study the utilization of the upcoming technology of Software Defined Radio in the implementation of physical layer security techniques. In the first part of thesis a general introduction and a briefly description of the evolution of wireless communications take place, in order for the reader to understand the reasons and motivations that lead to the development of this technology but also make clear the important role that this technology will play in communications field in the near future. Subsequently, an analytically introduction to Ettus Research’s USRP N210 is given, which recently obtained from the labs of School of Telecommunications and Electronics of Signals Officers and capabilities and restrictions of the device are given. In next two chapters an analysis of information security and physical layer security is taking place, while in chapter 5 the reader will find an attend of furthermore analysis of some physical layer’s techniques. In Chapter 6 of thesis a description of open source software GNURadio and program GNURadio Companion, which is a program to envelope real time applications, is given, while in chapter 7 is taking place the implementation of two kinds of transmitters, those of QAM and OFDM. Finally, this thesis ends with conclusions that came through the elaboration but also with suggestions for future work and possible use of Software Defined Radios in the implementation of physical layer’ s security techniques.