Physical Layer Security under Realistic Communication Conditions

• Applicant: Professor Dr.-Ing. Rafael Schaefer
• Subject Area: Electronic Semiconductors, Components and Circuits, Integrated Systems, Sensor Technology, Theoretical Electrical Engineering
• Term: from 2013 to 2015
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 244590776

Developments in communication systems make information available almost everywhere. Along with this, the security of sensitive information from unauthorised access becomes an important task which is usually realised by cryptographic techniques on higher layers. Such techniques are based on the availability of secret keys for encryption and on the assumption of insufficient computational capabilities of non-legitimate receivers. Especially wireless communication systems are inherently vulnerable for eavesdropping. The physical properties of the wireless channel make the communication accessible to external wiretappers, but also offer possibilities to establish security by other approaches than cryptographic techniques. In this context, the concept of physical layer security is becoming attractive, since it solely exploits the physical properties of the wireless channel to establish security.Practical implementations of this concept suffer from the fact that state-of-the-art research is carried out under idealistic communication conditions. Especially the assumption of perfect channel knowledge to non-legitimate receivers is too optimistic. Therefore, the overall purpose of this project is to deepen the understanding of physical layer security under realistic communication conditions which is an indispensable basis to bring this concept into practice. Based on the concepts of Shannon's Information Theory, this project will analyse the concept of physical layer security under different models of channel uncertainty and will characterise against what kind of eavesdropping strategies or attacks, information can be protected. In particular, important multi-user scenarios, such as multiple access or broadcast channels will be studied and corresponding capacity results will be derived. Finally, the impact of finite transmission block lengths on physical layer security techniques will be studied.

• DFG Programme: Research Fellowships
• International Connection: USA
• Host: Professor H. Vincent Poor, Ph.D.