Free-Space Optical (FSO) communication offers high data rates, low latency, and secure transmission, making it a promising candidate for Earth–Moon communication systems. However, its reliability is significantly affected by atmospheric conditions—particularly cloud coverage over Earth-based ground terminals. This thesis proposes an adaptive FSO communication framework for Earth–Moon links that utilizes real-time cloud distribution data to dynamically switch between geographically distributed ground stations, ensuring uninterrupted high-throughput communication. A detailed analysis of cloud models is conducted to understand their impact on FSO link attenuation. Based on this analysis, an algorithm is developed to predict ground station availability in a satellite constellationbased architecture. Two system configurations are examined: (1) a constellation of Earth-orbiting satellites enabling adaptive ground station selection, and (2) a direct Earth-to-lunar orbiter link, which is evaluated solely to analyze the impact of cloud coverage on link performance. Simulations are performed to assess the effect of atmospheric conditions on both scenarios. Areal-time decision-making module integrates satellite-based cloud monitoring, link availability estimates, and elevation constraints to determine the optimal ground terminal in the constellation-based system. This study highlights the potential of FSO communication as a key enabler of robust and high-capacity Earth–Moon communication by addressing the limitations imposed by Earth’s dynamic atmosphere.
La comunicazione ottica in spazio libero (FSO) offre elevate velocità di trasmissione dati, bassa latenza e trasmissione sicura, rendendola un candidato promettente per i sistemi di comunicazione Terra-Luna. Tuttavia, la sua affidabilità è significativamente influenzata dalle condizioni atmosferiche, in particolare dalla copertura nuvolosa sui terminali terrestri. Questa tesi propone un framework di comunicazione FSO adattivo per collegamenti Terra-Luna che utilizza i dati di distribuzione delle nuvole in tempo reale per commutare dinamicamente tra stazioni terrestri distribuite geograficamente, garantendo una comunicazione ininterrotta ad alta velocità. Viene condotta un'analisi dettagliata dei modelli di nuvole per comprenderne l'impatto sull'attenuazione del collegamento FSO. Sulla base di questa analisi, viene sviluppato un algoritmo per prevedere la disponibilità delle stazioni terrestri in un'architettura basata su una costellazione di satelliti. Vengono esaminate due configurazioni di sistema: (1) una costellazione di satelliti in orbita terrestre che consente la selezione adattiva delle stazioni terrestri e (2) un collegamento diretto Terra-Luna con un orbiter, che viene valutato esclusivamente per analizzare l'impatto della copertura nuvolosa sulle prestazioni del collegamento. Vengono eseguite simulazioni per valutare l'effetto delle condizioni atmosferiche su entrambi gli scenari. Il modulo decisionale in tempo reale integra il monitoraggio satellitare delle nubi, le stime di disponibilità dei collegamenti e i vincoli di elevazione per determinare il terminale di terra ottimale nel sistema basato sulla costellazione. Questo studio evidenzia il potenziale della comunicazione FSO come fattore chiave per una comunicazione Terra-Luna robusta e ad alta capacità, affrontando i limiti imposti dall'atmosfera dinamica terrestre.
Cloud aware framework for robust earth-moon free space optical communication
GHATOLE, PRIYANKA NITIN
2024/2025
Abstract
Free-Space Optical (FSO) communication offers high data rates, low latency, and secure transmission, making it a promising candidate for Earth–Moon communication systems. However, its reliability is significantly affected by atmospheric conditions—particularly cloud coverage over Earth-based ground terminals. This thesis proposes an adaptive FSO communication framework for Earth–Moon links that utilizes real-time cloud distribution data to dynamically switch between geographically distributed ground stations, ensuring uninterrupted high-throughput communication. A detailed analysis of cloud models is conducted to understand their impact on FSO link attenuation. Based on this analysis, an algorithm is developed to predict ground station availability in a satellite constellationbased architecture. Two system configurations are examined: (1) a constellation of Earth-orbiting satellites enabling adaptive ground station selection, and (2) a direct Earth-to-lunar orbiter link, which is evaluated solely to analyze the impact of cloud coverage on link performance. Simulations are performed to assess the effect of atmospheric conditions on both scenarios. Areal-time decision-making module integrates satellite-based cloud monitoring, link availability estimates, and elevation constraints to determine the optimal ground terminal in the constellation-based system. This study highlights the potential of FSO communication as a key enabler of robust and high-capacity Earth–Moon communication by addressing the limitations imposed by Earth’s dynamic atmosphere.| File | Dimensione | Formato | |
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2025-07-Ghatole.pdf
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Descrizione: This thesis presents an adaptive Free-Space Optical (FSO) communication framework for Earth–Moon links, addressing the significant impact of Earth's atmospheric conditions—particularly cloud coverage—on link reliability. The proposed system leverages real-time cloud distribution data to dynamically switch between geographically distributed ground stations, ensuring continuous high-throughput communication. Two configurations are analyzed: a direct Earth-to-Moon link and a constellation-based architecture with adaptive ground station selection. A comprehensive study of cloud models and their attenuation effects is conducted, followed by the development of a predictive algorithm for ground station availability. Simulations demonstrate that the relay-based system, supported by satellite-monitored cloud data and elevation constraints, significantly enhances link reliability. The study establishes FSO communication as a viable and scalable solution for robust Earth–Moon data transmission, overcoming the limitations of direct links under varying atmospheric conditions.
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https://hdl.handle.net/10589/241009