Increasing Physical Layer Security through Scrambled Codes and ARQ

TL;DR

This paper proposes a novel physical layer security method using concatenated scrambled codes combined with ARQ protocols, enhancing security even when eavesdropper and legitimate receiver channels are similar.

Contribution

It introduces concatenated scrambling techniques and ARQ integration to improve security on the AWGN wire-tap channel, reducing channel degradation requirements.

Findings

Concatenated scrambling enhances security with minimal channel degradation.

ARQ with authentication enables security when channels are similar.

The method maintains high transmission security with small performance trade-offs.

Abstract

We develop the proposal of non-systematic channel codes on the AWGN wire-tap channel. Such coding technique, based on scrambling, achieves high transmission security with a small degradation of the eavesdropper's channel with respect to the legitimate receiver's channel. In this paper, we show that, by implementing scrambling and descrambling on blocks of concatenated frames, rather than on single frames, the channel degradation needed is further reduced. The usage of concatenated scrambling allows to achieve security also when both receivers experience the same channel quality. However, in this case, the introduction of an ARQ protocol with authentication is needed.