A Novel Hybrid Optical and STAR IRS System for NTN Communications

Shunyuan Shang; Emna Zedini; Abla Kammoun; Mohamed-Slim Alouini

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arXiv · 2508.03147

A Novel Hybrid Optical and STAR IRS System for NTN Communications

Shunyuan Shang·Emna Zedini·Abla Kammoun·Mohamed-Slim Alouini

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Abstract

This paper proposes a novel non-terrestrial networks (NTNs) system that integrates optical intelligent reflecting surfaces (OIRS) and simultaneous transmitting and reflecting Intelligent reflecting surfaces (STAR-IRS) to address critical challenges in next-generation communication networks. The proposed system model features a signal transmitted from the optical ground station (OGS) to the earth station (ES) via an OIRS mounted horizontally on a high altitude platform (HAP). The ES uses an amplify-and-forward (AF) relay with fixed gain for signal relaying, which is then transmitted through a STAR-IRS vertically installed on a building to facilitate communication with both indoor and outdoor users. The FSO link incorporates (multiple-input multiple-output) MIMO technology, and this paper develops a channel model specifically designed for scenarios where the number of OIRS units exceeds one. For the radio-frequency (RF) link, a novel and highly precise approximation method is introduced, offering superior accuracy compared to traditional approaches based on the central limit theorem (CLT). Closed-form analytical expressions for key performance metrics, including outage probability (OP), ergodic capacity and average bit error rate (BER) are derived in terms of the bivariate Fox-H function for this novel five hops system. Asymptotic expressions at high SNR are also presented, providing insights into system diversity order.

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Shunyuan Shang, Emna Zedini, Abla Kammoun, Mohamed-Slim Alouini. 2025-08-05. A Novel Hybrid Optical and STAR IRS System for NTN Communications. https://arxiv.org/abs/2508.03147

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