Polar Coding for Physical-Layer Security

Conference: WSA & SCC 2023 - 26th International ITG Workshop on Smart Antennas and 13th Conference on Systems, Communications, and Coding
02/27/2023 at Braunschweig, Germany

Proceedings: ITG-Fb. 308: WSA & SCC 2023

Pages: 6Language: englishTyp: PDF

Authors:
Pfeiffer, Johannes; Fischer, Robert F.H. (Institute of Communications Engineering, Ulm University, Germany)

Abstract:
In physical-layer security schemes, coding and modulation are used to prevent successful eavesdropping without the need for secret keys. In this paper, we analyze practical polar coding schemes w.r.t. the BER-based security gap metric in a Gaussian wiretap channel scenario. Thereby, individual secrecy metrics are derived for the information symbols conveyed within a codeword. The unequal protection of communicated information symbols is revealed and a trade-off between secure transmission rate and secrecy is presented. Further, a suitable combination of polar codes with (information-symbol) scrambling schemes is derived by taking the inherent scrambling of common polar encoding strategies into account. The theoretical findings are supported by numerical simulations.