Enhanced Multiuser CSI-Based Physical Layer Authentication Based on Information Reconciliation

TL;DR

This work tackles CSI-based physical-layer authentication (PLA) in multiuser networks by introducing an information-reconciliation framework that uses Polar codes combined with a flexible quantization scheme. By applying Slepian–Wolf coding to reconcile time-dispersed CSI observations, the method collapses legitimate-user CSI representations, enhancing discriminability against an impersonator (Mallory). CRC–aided list decoding for Polar codes with side information enables robust reconciliation under realistic noise and interference, achieving near-perfect detection with extremely low false alarm rates. The proposed approach outperforms prior PLA schemes, offering a practical, low-complexity, quantum-resistant solution for securing IoT and other multiuser wireless systems.

Abstract

This paper presents a physical layer authentication (PLA) technique using information reconciliation in multiuser communication systems. A cost-effective solution for low-end Internet of Things networks can be provided by PLA. In this work, we develop an information reconciliation scheme using Polar codes along with a quantization strategy that employs an arbitrary number of bits to enhance the performance of PLA. We employ the principle of Slepian-Wolf coding to reconcile channel measurements spread in time. Numerical results show that our approach works very well and outperforms competing approaches, achieving more than 99.80% increase in detection probability for false alarm probabilities close to 0.

Figures (7)

• Figure 1: Multiuser system with interference
• Figure 2: Proposed PLA scheme, $u\in \{a,m\}$
• Figure 3: Simulated vs closed-from expression: code rate $= 0.01$, $SNR = 10~dB$, $p_0 \approx 0$ and $p_1 \approx 0.4539$
• Figure 4: ROC curve: $SNR = 5~dB$
• Figure 5: $P_D$ vs $SNR$: $P_{FA} = 10^{-3}$