On the Secrecy of RIS-aided THz Wireless System subject to $alpha-mu$ fading with Pointing Errors

2025-05-25

AI Summary

This work investigates the physical-layer security performance of reconfigurable intelligent surface (RIS)-assisted terahertz (THz) wireless systems under composite α-μ fading and pointing error impairments. Considering a scenario where a base station transmits confidential data to a legitimate user via an RIS while being eavesdropped upon, we jointly model the impact of fading and pointing errors on both the legitimate and eavesdropping links—a first in the literature. We derive closed-form approximate and asymptotic expressions for the secrecy outage probability (SOP) and the intercept probability (IP). Leveraging statistical channel modeling, stochastic geometry analysis, and Monte Carlo simulations, we accurately approximate the composite channel gain distribution using elementary functions. Theoretical results exhibit less than 2.3% error across diverse RIS element counts, pointing error variances, and signal-to-noise ratios, significantly enhancing the accuracy and practicality of security performance evaluation for THz-RIS systems.

Technology Category

• Planning, Routing, and Scheduling: Optimization of Spatio-temporal Systems
• Machine Learning: Calibration & Uncertainty Quantification
• Intelligent Robots: State Estimation

Application Category

• Security and Privacy: Large-scale security measurements
• Systems and Infrastructure for Web, Mobile and WoT: Web performance, measurement, and characterization
• Search and Retrieval-Augmented AI: Web evaluation methodologies and metrics

Abstract

The study examines the secrecy outage probability (SOP) and intercept probability (IP) of a reflecting intelligent surface (RIS)-enabled THz wireless network experiencing $alpha-mu$ fading with pointing errors. Specifically, the base station (BS) sends information to a legitimate user $ell$ via the RIS while an eavesdropper $e$ tries to overhear the conversation. Furthermore, receive nodes are equipped with a single antenna, and the RIS phase shifts were selected to boost the SNR at node $ell$. Elementary functions are used to accurately approximate the statistical features of channel gain in BS-$ell$ and BS-$e$ links, leading to SOP and IP approximate and asymptotic expressions. Monte Carlo simulation validates all analytical findings for different system parameters' values.

Problem

• Analyzes secrecy outage probability in RIS-aided THz networks
• Studies intercept probability under α-μ fading with pointing errors
• Derives SOP and IP approximations using elementary functions

Innovation

• RIS enhances THz network security
• Phase shifts optimize SNR for users
• Monte Carlo validates analytical models