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arXiv · 2607.02724

Signal from Space: Detecting Schools and Towers to Bridge the Digital Divide

Abstract

Reliable internet access is essential for modern education, yet millions of school-aged children especially in developing regions remain offline due to unconnected schools. The Giga Initiative aims to connect every school to the internet, but doing so at scale requires efficient methods to map schools and assess surrounding connectivity infrastructure without relying on sparse or noisy third-party datasets. In this work, we propose a scalable, vision-only framework that uses high-resolution satellite imagery and transfer learning to address both tasks simultaneously. By adapting pre-trained object detection models to new geographical regions with minimal labeled data, we detect schools and cell towers directly from space. We then analyze the spatial relationship between detected schools and nearby towers as a proxy for connectivity availability. This purely imagery-driven pipeline enables large-scale infrastructure mapping, reduces dependency on auxiliary data, and supports data-driven prioritization of connectivity investments in underserved areas. Our approach is demonstrated on real satellite imagery from Lesotho, showing strong performance across this region.

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Zakarya Elmimouni, Sandor Farkas, Fares Fourati, Vladimir Daigele, Walid Mathlouthi, Mohamed-Slim Alouini. 2026-07-02. Signal from Space: Detecting Schools and Towers to Bridge the Digital Divide. https://arxiv.org/abs/2607.02724

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